【android开发】自定义数字软键盘的设计与实现（1）

相信很多情况下我们看到过一些数字的输入，弹出来的并不是系统自带的键盘。这就是自定义的软键盘，软键盘的一个好处就是简单，操作方便。如何实现一个自定义的软键盘呢？？其实这个过程是比较简单的，只要把几个关键的原理搞明白了，你就会发现真的很简单，很方便！看一下效果图：



这篇博客主要介绍一下实现的相关原理，下一节就会把具体实现的步骤和大家分享一下！

实现软键盘主要用到了系统的两个类Keyboard和KeyboardView:

Keyboard类源码的介绍是： Listener for virtual keyboard events.即用于监听虚拟键盘。

至于Keyboard类的映射机制，这里就不需要说了，本人感觉也没必要了解的太深，这里要介绍一些他，在接下来需要的几个重要的内容。我们看一下他的源码：

package com.android.inputmethod.keyboard;

import android.util.Log;
import android.util.SparseArray;
import com.android.inputmethod.keyboard.internal.KeyVisualAttributes;
import com.android.inputmethod.keyboard.internal.KeyboardIconsSet;
import com.android.inputmethod.keyboard.internal.KeyboardParams;
import com.android.inputmethod.latin.CollectionUtils;

/**
* Loads an XML description of a keyboard and stores the attributes of the keys. A keyboard
* consists of rows of keys.
* <p>The layout file for a keyboard contains XML that looks like the following snippet:</p>
* <pre>
* <Keyboard
*         latin:keyWidth="%10p"
*         latin:keyHeight="50px"
*         latin:horizontalGap="2px"
*         latin:verticalGap="2px" >
*     <Row latin:keyWidth="32px" >
*         <Key latin:keyLabel="A" />
*         ...
*     </Row>
*     ...
* </Keyboard>
* </pre>
*/
public class Keyboard {
private static final String TAG = Keyboard.class.getSimpleName();

/** Some common keys code. Must be positive.
* These should be aligned with values/keycodes.xml
*/
public static final int CODE_ENTER = '\n';
public static final int CODE_TAB = '\t';
public static final int CODE_SPACE = ' ';
public static final int CODE_PERIOD = '.';
public static final int CODE_DASH = '-';
public static final int CODE_SINGLE_QUOTE = '\'';
public static final int CODE_DOUBLE_QUOTE = '"';
public static final int CODE_QUESTION_MARK = '?';
public static final int CODE_EXCLAMATION_MARK = '!';
// TODO: Check how this should work for right-to-left languages. It seems to stand
// that for rtl languages, a closing parenthesis is a left parenthesis. Is this
// managed by the font? Or is it a different char?
public static final int CODE_CLOSING_PARENTHESIS = ')';
public static final int CODE_CLOSING_SQUARE_BRACKET = ']';
public static final int CODE_CLOSING_CURLY_BRACKET = '}';
public static final int CODE_CLOSING_ANGLE_BRACKET = '>';
/** Special keys code. Must be negative.
* These should be aligned with KeyboardCodesSet.ID_TO_NAME[],
* KeyboardCodesSet.DEFAULT[] and KeyboardCodesSet.RTL[]
*/
public static final int CODE_SHIFT = -1;
public static final int CODE_SWITCH_ALPHA_SYMBOL = -2;
public static final int CODE_OUTPUT_TEXT = -3;
public static final int CODE_DELETE = -4;
public static final int CODE_SETTINGS = -5;
public static final int CODE_SHORTCUT = -6;
public static final int CODE_ACTION_ENTER = -7;
public static final int CODE_ACTION_NEXT = -8;
public static final int CODE_ACTION_PREVIOUS = -9;
public static final int CODE_LANGUAGE_SWITCH = -10;
public static final int CODE_RESEARCH = -11;
// Code value representing the code is not specified.
public static final int CODE_UNSPECIFIED = -12;
public final KeyboardId mId;
public final int mThemeId;

/** Total height of the keyboard, including the padding and keys */
public final int mOccupiedHeight;
/** Total width of the keyboard, including the padding and keys */
public final int mOccupiedWidth;
/** The padding above the keyboard */
public final int mTopPadding;
/** Default gap between rows */
public final int mVerticalGap;

/** Per keyboard key visual parameters */
public final KeyVisualAttributes mKeyVisualAttributes;
public final int mMostCommonKeyHeight;
public final int mMostCommonKeyWidth;
/** More keys keyboard template */
public final int mMoreKeysTemplate;
/** Maximum column for more keys keyboard */
public final int mMaxMoreKeysKeyboardColumn;
/** Array of keys and icons in this keyboard */
public final Key[] mKeys;
public final Key[] mShiftKeys;
public final Key[] mAltCodeKeysWhileTyping;
public final KeyboardIconsSet mIconsSet;
private final SparseArray<Key> mKeyCache = CollectionUtils.newSparseArray();
private final ProximityInfo mProximityInfo;
private final boolean mProximityCharsCorrectionEnabled;
public Keyboard(final KeyboardParams params) {
/// M: @{
ProximityInfo tmp;
/// @}
mId = params.mId;
mThemeId = params.mThemeId;
mOccupiedHeight = params.mOccupiedHeight;
mOccupiedWidth = params.mOccupiedWidth;
mMostCommonKeyHeight = params.mMostCommonKeyHeight;
mMostCommonKeyWidth = params.mMostCommonKeyWidth;
mMoreKeysTemplate = params.mMoreKeysTemplate;
mMaxMoreKeysKeyboardColumn = params.mMaxMoreKeysKeyboardColumn;
mKeyVisualAttributes = params.mKeyVisualAttributes;
mTopPadding = params.mTopPadding;
mVerticalGap = params.mVerticalGap;
mKeys = params.mKeys.toArray(new Key[params.mKeys.size()]);
mShiftKeys = params.mShiftKeys.toArray(new Key[params.mShiftKeys.size()]);
mAltCodeKeysWhileTyping = params.mAltCodeKeysWhileTyping.toArray(
new Key[params.mAltCodeKeysWhileTyping.size()]);
mIconsSet = params.mIconsSet;
/// M: Modified by MTK to avoid OOME thrown to DVM on LCA
//     since there is an int array sized about 32KB allocated
//     within ProximityInfo constructor. @{
try {
tmp = new ProximityInfo(params.mId.mLocale.toString(),
params.GRID_WIDTH, params.GRID_HEIGHT, mOccupiedWidth, mOccupiedHeight,
mMostCommonKeyWidth, mMostCommonKeyHeight, mKeys, params.mTouchPositionCorrection);
} catch (OutOfMemoryError e) {
Log.w(TAG, "OutOfMemoryError at ProximityInfo");
/// M: It`s dangerous here, since this approach will generate
//     a proximity useless, this will cause no responce on VK.
// TODO: It`s better to unbind LatinIME here or provide another
//       keyboard here.
tmp = ProximityInfo.createDummyProximityInfo();
}
mProximityInfo = tmp;
/// @}
mProximityCharsCorrectionEnabled = params.mProximityCharsCorrectionEnabled;
}
public boolean hasProximityCharsCorrection(final int code) {
if (!mProximityCharsCorrectionEnabled) {
return false;
}
// Note: The native code has the main keyboard layout only at this moment.
// TODO: Figure out how to handle proximity characters information of all layouts.
final boolean canAssumeNativeHasProximityCharsInfoOfAllKeys = (
mId.mElementId == KeyboardId.ELEMENT_ALPHABET
|| mId.mElementId == KeyboardId.ELEMENT_ALPHABET_AUTOMATIC_SHIFTED);
return canAssumeNativeHasProximityCharsInfoOfAllKeys || Character.isLetter(code);
}
public ProximityInfo getProximityInfo() {
return mProximityInfo;
}
public Key getKey(final int code) {
if (code == CODE_UNSPECIFIED) {
return null;
}
synchronized (mKeyCache) {
final int index = mKeyCache.indexOfKey(code);
if (index >= 0) {
return mKeyCache.valueAt(index);
}
for (final Key key : mKeys) {
if (key.mCode == code) {
mKeyCache.put(code, key);
return key;
}
}
mKeyCache.put(code, null);
return null;
}
}
public boolean hasKey(final Key aKey) {
if (mKeyCache.indexOfValue(aKey) >= 0) {
return true;
}

for (final Key key : mKeys) {
if (key == aKey) {
mKeyCache.put(key.mCode, key);
return true;
}
}
return false;
}
public static boolean isLetterCode(final int code) {
return code >= CODE_SPACE;
}
@Override
public String toString() {
return mId.toString();
}
/**
* Returns the array of the keys that are closest to the given point.
* @param x the x-coordinate of the point
* @param y the y-coordinate of the point
* @return the array of the nearest keys to the given point. If the given
* point is out of range, then an array of size zero is returned.
*/
public Key[] getNearestKeys(final int x, final int y) {
// Avoid dead pixels at edges of the keyboard
final int adjustedX = Math.max(0, Math.min(x, mOccupiedWidth - 1));
final int adjustedY = Math.max(0, Math.min(y, mOccupiedHeight - 1));
return mProximityInfo.getNearestKeys(adjustedX, adjustedY);
}
public static String printableCode(final int code) {
switch (code) {
case CODE_SHIFT: return "shift";
case CODE_SWITCH_ALPHA_SYMBOL: return "symbol";
case CODE_OUTPUT_TEXT: return "text";
case CODE_DELETE: return "delete";
case CODE_SETTINGS: return "settings";
case CODE_SHORTCUT: return "shortcut";
case CODE_ACTION_ENTER: return "actionEnter";
case CODE_ACTION_NEXT: return "actionNext";
case CODE_ACTION_PREVIOUS: return "actionPrevious";
case CODE_LANGUAGE_SWITCH: return "languageSwitch";
case CODE_UNSPECIFIED: return "unspec";
case CODE_TAB: return "tab";
case CODE_ENTER: return "enter";
default:
if (code <= 0) Log.w(TAG, "Unknown non-positive key code=" + code);
if (code < CODE_SPACE) return String.format("'\\u%02x'", code);
if (code < 0x100) return String.format("'%c'", code);
return String.format("'\\u%04x'", code);
}
}
}

我们在设置每一个按键的code时，就是根据keyboard类中定义的一些属性，比如回退，删除，清空等都是固定。

知道了

    public static final int CODE_SHIFT = -1;

    public static final int CODE_SWITCH_ALPHA_SYMBOL = -2;

    public static final int CODE_OUTPUT_TEXT = -3;

    public static final int CODE_DELETE = -4;

    public static final int CODE_SETTINGS = -5;

    public static final int CODE_SHORTCUT = -6;

    public static final int CODE_ACTION_ENTER = -7;

    public static final int CODE_ACTION_NEXT = -8;

    public static final int CODE_ACTION_PREVIOUS = -9;

    public static final int CODE_LANGUAGE_SWITCH = -10;

    public static final int CODE_RESEARCH = -11;

    // Code value representing the code is not specified.

    public static final int CODE_UNSPECIFIED = -12;

我们就不会有太多的疑惑了！也是说，我们自定义的每一个按键都将会有一个codes值，比如回退我们就写成：<Key android:codes="-5" android:keyIcon="@drawable/sym_keyboard_delete"/>

在监听就是：if (primaryCode == Keyboard.KEYCODE_DELETE){}.这就表示，监听回退事件了！

KeyboardView类源码的介绍是： A view that renders a virtual {@link Keyboard}. It handles rendering of keys and detecting key presses and touch movements.即它处理绘制钥匙和检测按键和触摸动作。源代码如下：

/*
* Copyright (C) 2008-2012  OMRON SOFTWARE Co., Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0 *
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* This file is porting from Android framework.
*   frameworks/base/core/java/android/inputmethodservice/KeyboardView.java
*
*package android.inputmethodservice;
*/

package jp.co.omronsoft.openwnn;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.Rect;
import android.graphics.Typeface;
import android.graphics.Paint.Align;
import android.graphics.Region.Op;
import android.graphics.drawable.Drawable;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.GestureDetector;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup.LayoutParams;
import android.widget.PopupWindow;
import android.widget.TextView;

import jp.co.omronsoft.openwnn.Keyboard;
import jp.co.omronsoft.openwnn.Keyboard.Key;

import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
* A view that renders a virtual {@link Keyboard}. It handles rendering of keys and
* detecting key presses and touch movements.
*/
public class KeyboardView extends View implements View.OnClickListener {

/**
* Listener for virtual keyboard events.
*/
public interface OnKeyboardActionListener {

/**
* Called when the user presses a key. This is sent before the {@link #onKey} is called.
* For keys that repeat, this is only called once.
* @param primaryCode the unicode of the key being pressed. If the touch is not on a valid
* key, the value will be zero.
*/
void onPress(int primaryCode);

/**
* Called when the user releases a key. This is sent after the {@link #onKey} is called.
* For keys that repeat, this is only called once.
* @param primaryCode the code of the key that was released
*/
void onRelease(int primaryCode);

/**
* Send a key press to the listener.
* @param primaryCode this is the key that was pressed
* @param keyCodes the codes for all the possible alternative keys
* with the primary code being the first. If the primary key code is
* a single character such as an alphabet or number or symbol, the alternatives
* will include other characters that may be on the same key or adjacent keys.
* These codes are useful to correct for accidental presses of a key adjacent to
* the intended key.
*/
void onKey(int primaryCode, int[] keyCodes);

/**
* Sends a sequence of characters to the listener.
* @param text the sequence of characters to be displayed.
*/
void onText(CharSequence text);

/**
* Called when the user quickly moves the finger from right to left.
*/
void swipeLeft();

/**
* Called when the user quickly moves the finger from left to right.
*/
void swipeRight();

/**
* Called when the user quickly moves the finger from up to down.
*/
void swipeDown();

/**
* Called when the user quickly moves the finger from down to up.
*/
void swipeUp();

/**
* Called when the user long presses a key.
* @param popupKey the key that was long pressed
* @return true if the long press is handled, false otherwise.
*/
boolean onLongPress(Keyboard.Key key);
}

private static final int NOT_A_KEY = -1;
private static final int[] KEY_DELETE = { Keyboard.KEYCODE_DELETE };
private static final int[] LONG_PRESSABLE_STATE_SET = {
android.R.attr.state_long_pressable
};

private Keyboard mKeyboard;
private int mCurrentKeyIndex = NOT_A_KEY;
private int mLabelTextSize;
private int mKeyTextSize;
private int mKeyTextColor;
private int mKeyTextColor2nd;
private float mShadowRadius;
private int mShadowColor;
private float mBackgroundDimAmount;

private TextView mPreviewText;
private PopupWindow mPreviewPopup;
private int mPreviewTextSizeLarge;
private int mPreviewOffset;
private int mPreviewHeight;
private int[] mOffsetInWindow;

private PopupWindow mPopupKeyboard;
private View mMiniKeyboardContainer;
private KeyboardView mMiniKeyboard;
private boolean mMiniKeyboardOnScreen;
private View mPopupParent;
private int mMiniKeyboardOffsetX;
private int mMiniKeyboardOffsetY;
private Map<Key,View> mMiniKeyboardCache;
private int[] mWindowOffset;
private Key[] mKeys;

/** Listener for {@link OnKeyboardActionListener}. */
private OnKeyboardActionListener mKeyboardActionListener;

private static final int MSG_SHOW_PREVIEW = 1;
private static final int MSG_REMOVE_PREVIEW = 2;
private static final int MSG_REPEAT = 3;
private static final int MSG_LONGPRESS = 4;

private static final int DELAY_BEFORE_PREVIEW = 0;
private static final int DELAY_AFTER_PREVIEW = 70;
private static final int DEBOUNCE_TIME = 70;

private int mVerticalCorrection;
private int mProximityThreshold;

private boolean mPreviewCentered = false;
private boolean mShowPreview = true;
private boolean mShowTouchPoints = true;
private int mPopupPreviewX;
private int mPopupPreviewY;
private int mWindowY;

private int mLastX;
private int mLastY;
private int mStartX;
private int mStartY;

private boolean mProximityCorrectOn;

private Paint mPaint;
private Rect mPadding;

private long mDownTime;
private long mLastMoveTime;
private int mLastKey;
private int mLastCodeX;
private int mLastCodeY;
private int mCurrentKey = NOT_A_KEY;
private int mDownKey = NOT_A_KEY;
private long mLastKeyTime;
private long mCurrentKeyTime;
private int[] mKeyIndices = new int[12];
private GestureDetector mGestureDetector;
private int mPopupX;
private int mPopupY;
private int mRepeatKeyIndex = NOT_A_KEY;
private int mPopupLayout;
private boolean mAbortKey;
private Key mInvalidatedKey;
private Rect mClipRegion = new Rect(0, 0, 0, 0);
private boolean mPossiblePoly;
private SwipeTracker mSwipeTracker = new SwipeTracker();
private int mSwipeThreshold;
private boolean mDisambiguateSwipe;

private int mOldPointerCount = 1;
private float mOldPointerX;
private float mOldPointerY;

private Drawable mKeyBackground;
private Drawable mKeyBackground2nd;

private static final int REPEAT_INTERVAL = 50;
private static final int REPEAT_START_DELAY = 400;
private static final int LONGPRESS_TIMEOUT = ViewConfiguration.getLongPressTimeout();

private static int MAX_NEARBY_KEYS = 12;
private int[] mDistances = new int[MAX_NEARBY_KEYS];

private int mLastSentIndex;
private int mTapCount;
private long mLastTapTime;
private boolean mInMultiTap;
private static final int MULTITAP_INTERVAL = 800;
private StringBuilder mPreviewLabel = new StringBuilder(1);

/** Whether the keyboard bitmap needs to be redrawn before it's blitted. **/
private boolean mDrawPending;
/** The dirty region in the keyboard bitmap */
private Rect mDirtyRect = new Rect();
/** The keyboard bitmap for faster updates */
private Bitmap mBuffer;
/** Notes if the keyboard just changed, so that we could possibly reallocate the mBuffer. */
private boolean mKeyboardChanged;
/** The canvas for the above mutable keyboard bitmap */
private Canvas mCanvas;

Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_SHOW_PREVIEW:
showKey(msg.arg1);
break;
case MSG_REMOVE_PREVIEW:
mPreviewText.setVisibility(INVISIBLE);
break;
case MSG_REPEAT:
if (repeatKey()) {
Message repeat = Message.obtain(this, MSG_REPEAT);
sendMessageDelayed(repeat, REPEAT_INTERVAL);
}
break;
case MSG_LONGPRESS:
openPopupIfRequired((MotionEvent) msg.obj);
break;
}
}
};

/** Constructor */
public KeyboardView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

/** Constructor */
public KeyboardView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);

TypedArray a =
context.obtainStyledAttributes(
attrs, android.R.styleable.KeyboardView, defStyle, R.style.WnnKeyboardView);

LayoutInflater inflate =
(LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

int previewLayout = 0;
int keyTextSize = 0;

int n = a.getIndexCount();

for (int i = 0; i < n; i++) {
int attr = a.getIndex(i);

switch (attr) {
case android.R.styleable.KeyboardView_keyBackground:
mKeyBackground = a.getDrawable(attr);
break;
case android.R.styleable.KeyboardView_verticalCorrection:
mVerticalCorrection = a.getDimensionPixelOffset(attr, 0);
break;
case android.R.styleable.KeyboardView_keyPreviewLayout:
previewLayout = a.getResourceId(attr, 0);
break;
case android.R.styleable.KeyboardView_keyPreviewOffset:
mPreviewOffset = a.getDimensionPixelOffset(attr, 0);
break;
case android.R.styleable.KeyboardView_keyPreviewHeight:
mPreviewHeight = a.getDimensionPixelSize(attr, 80);
break;
case android.R.styleable.KeyboardView_keyTextSize:
mKeyTextSize = a.getDimensionPixelSize(attr, 18);
break;
case android.R.styleable.KeyboardView_keyTextColor:
mKeyTextColor = a.getColor(attr, 0xFF000000);
break;
case android.R.styleable.KeyboardView_labelTextSize:
mLabelTextSize = a.getDimensionPixelSize(attr, 14);
break;
case android.R.styleable.KeyboardView_popupLayout:
mPopupLayout = a.getResourceId(attr, 0);
break;
case android.R.styleable.KeyboardView_shadowColor:
mShadowColor = a.getColor(attr, 0);
break;
case android.R.styleable.KeyboardView_shadowRadius:
mShadowRadius = a.getFloat(attr, 0f);
break;
}
}

a.recycle();
a = context.obtainStyledAttributes(attrs, R.styleable.WnnKeyboardView, 0, 0);
mKeyBackground2nd = a.getDrawable(R.styleable.WnnKeyboardView_keyBackground2nd);
mKeyTextColor2nd = a.getColor(R.styleable.WnnKeyboardView_keyTextColor2nd, 0xFF000000);

a.recycle();
a = mContext.obtainStyledAttributes(
android.R.styleable.Theme);
mBackgroundDimAmount = a.getFloat(android.R.styleable.Theme_backgroundDimAmount, 0.5f);

mPreviewPopup = new PopupWindow(context);
if (previewLayout != 0) {
mPreviewText = (TextView) inflate.inflate(previewLayout, null);
mPreviewTextSizeLarge = (int) mPreviewText.getTextSize();
mPreviewPopup.setContentView(mPreviewText);
mPreviewPopup.setBackgroundDrawable(null);
} else {
mShowPreview = false;
}

mPreviewPopup.setTouchable(false);

mPopupKeyboard = new PopupWindow(context);
mPopupKeyboard.setBackgroundDrawable(null);

mPopupParent = this;

mPaint = new Paint();
mPaint.setAntiAlias(true);
mPaint.setTextSize(keyTextSize);
mPaint.setTextAlign(Align.CENTER);
mPaint.setAlpha(255);

mPadding = new Rect(0, 0, 0, 0);
mMiniKeyboardCache = new HashMap<Key,View>();
mKeyBackground.getPadding(mPadding);

mSwipeThreshold = (int) (500 * getResources().getDisplayMetrics().density);

mDisambiguateSwipe = true;

resetMultiTap();
initGestureDetector();
}

private void initGestureDetector() {
mGestureDetector = new GestureDetector(getContext(), new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onFling(MotionEvent me1, MotionEvent me2,
float velocityX, float velocityY) {
if (mPossiblePoly) return false;
final float absX = Math.abs(velocityX);
final float absY = Math.abs(velocityY);
float deltaX = me2.getX() - me1.getX();
float deltaY = me2.getY() - me1.getY();
int travelX = getWidth() / 2;
int travelY = getHeight() / 2;
mSwipeTracker.computeCurrentVelocity(1000);
final float endingVelocityX = mSwipeTracker.getXVelocity();
final float endingVelocityY = mSwipeTracker.getYVelocity();
boolean sendDownKey = false;
if (velocityX > mSwipeThreshold && absY < absX && deltaX > travelX) {
if (mDisambiguateSwipe && endingVelocityX < velocityX / 4) {
sendDownKey = true;
} else {
swipeRight();
return true;
}
} else if (velocityX < -mSwipeThreshold && absY < absX && deltaX < -travelX) {
if (mDisambiguateSwipe && endingVelocityX > velocityX / 4) {
sendDownKey = true;
} else {
swipeLeft();
return true;
}
} else if (velocityY < -mSwipeThreshold && absX < absY && deltaY < -travelY) {
if (mDisambiguateSwipe && endingVelocityY > velocityY / 4) {
sendDownKey = true;
} else {
swipeUp();
return true;
}
} else if (velocityY > mSwipeThreshold && absX < absY / 2 && deltaY > travelY) {
if (mDisambiguateSwipe && endingVelocityY < velocityY / 4) {
sendDownKey = true;
} else {
swipeDown();
return true;
}
}

if (sendDownKey) {
detectAndSendKey(mDownKey, mStartX, mStartY, me1.getEventTime());
}
return false;
}
});

mGestureDetector.setIsLongpressEnabled(false);
}

/**
* Set the {@link OnKeyboardActionListener} object.
* @param listener  The OnKeyboardActionListener to set.
*/
public void setOnKeyboardActionListener(OnKeyboardActionListener listener) {
mKeyboardActionListener = listener;
}

/**
* Returns the {@link OnKeyboardActionListener} object.
* @return the listener attached to this keyboard
*/
protected OnKeyboardActionListener getOnKeyboardActionListener() {
return mKeyboardActionListener;
}

/**
* Attaches a keyboard to this view. The keyboard can be switched at any time and the
* view will re-layout itself to accommodate the keyboard.
* @see Keyboard
* @see #getKeyboard()
* @param keyboard the keyboard to display in this view
*/
public void setKeyboard(Keyboard keyboard) {
if (!keyboard.equals(mKeyboard)) {
clearWindowInfo();
}
int oldRepeatKeyCode = NOT_A_KEY;
if (mKeyboard != null) {
showPreview(NOT_A_KEY);
if ((mRepeatKeyIndex != NOT_A_KEY) && (mRepeatKeyIndex < mKeys.length)) {
oldRepeatKeyCode = mKeys[mRepeatKeyIndex].codes[0];
}
}
removeMessages();
mKeyboard = keyboard;
List<Key> keys = mKeyboard.getKeys();
mKeys = keys.toArray(new Key[keys.size()]);
requestLayout();
mKeyboardChanged = true;
invalidateAllKeys();
computeProximityThreshold(keyboard);
mMiniKeyboardCache.clear();
boolean abort = true;
if (oldRepeatKeyCode != NOT_A_KEY) {
int keyIndex = getKeyIndices(mStartX, mStartY, null);
if ((keyIndex != NOT_A_KEY)
&& (keyIndex < mKeys.length)
&& (oldRepeatKeyCode == mKeys[keyIndex].codes[0])) {
abort = false;
mRepeatKeyIndex = keyIndex;
}
}
if (abort) {
mHandler.removeMessages(MSG_REPEAT);
}
mAbortKey = abort;
}

/**
* Returns the current keyboard being displayed by this view.
* @return the currently attached keyboard
* @see #setKeyboard(Keyboard)
*/
public Keyboard getKeyboard() {
return mKeyboard;
}

/**
* Sets the state of the shift key of the keyboard, if any.
* @param shifted whether or not to enable the state of the shift key
* @return true if the shift key state changed, false if there was no change
* @see KeyboardView#isShifted()
*/
public boolean setShifted(boolean shifted) {
if (mKeyboard != null) {
if (mKeyboard.setShifted(shifted)) {
invalidateAllKeys();
return true;
}
}
return false;
}

/**
* Returns the state of the shift key of the keyboard, if any.
* @return true if the shift is in a pressed state, false otherwise. If there is
* no shift key on the keyboard or there is no keyboard attached, it returns false.
* @see KeyboardView#setShifted(boolean)
*/
public boolean isShifted() {
if (mKeyboard != null) {
return mKeyboard.isShifted();
}
return false;
}

/**
* Enables or disables the key feedback popup. This is a popup that shows a magnified
* version of the depressed key. By default the preview is enabled.
* @param previewEnabled whether or not to enable the key feedback popup
* @see #isPreviewEnabled()
*/
public void setPreviewEnabled(boolean previewEnabled) {
mShowPreview = previewEnabled;
}

/**
* Returns the enabled state of the key feedback popup.
* @return whether or not the key feedback popup is enabled
* @see #setPreviewEnabled(boolean)
*/
public boolean isPreviewEnabled() {
return mShowPreview;
}

/**
* Returns the root parent has the enabled state of the key feedback popup.
* @return whether or not the key feedback popup is enabled
* @see #setPreviewEnabled(boolean)
*/
public boolean isParentPreviewEnabled() {
if ((mPopupParent != null) && (mPopupParent != this)
&& (mPopupParent instanceof KeyboardView)) {
return ((KeyboardView)mPopupParent).isParentPreviewEnabled();
} else {
return mShowPreview;
}
}

public void setVerticalCorrection(int verticalOffset) {

}

/**
* Set View on the PopupParent.
* @param v  The View to set.
*/
public void setPopupParent(View v) {
mPopupParent = v;
}

/**
* Set parameters on the KeyboardOffset.
* @param x  The value of KeyboardOffset.
* @param y  The value of KeyboardOffset.
*/
public void setPopupOffset(int x, int y) {
mMiniKeyboardOffsetX = x;
mMiniKeyboardOffsetY = y;
if (mPreviewPopup.isShowing()) {
mPreviewPopup.dismiss();
}
}

/**
* When enabled, calls to {@link OnKeyboardActionListener#onKey} will include key
* codes for adjacent keys.  When disabled, only the primary key code will be
* reported.
* @param enabled whether or not the proximity correction is enabled
*/
public void setProximityCorrectionEnabled(boolean enabled) {
mProximityCorrectOn = enabled;
}

/**
* Returns true if proximity correction is enabled.
*/
public boolean isProximityCorrectionEnabled() {
return mProximityCorrectOn;
}

/**
* Popup keyboard close button clicked.
* @hide
*/
public void onClick(View v) {
dismissPopupKeyboard();
}

private CharSequence adjustCase(CharSequence label) {
if (mKeyboard.isShifted() && label != null && label.length() < 3
&& Character.isLowerCase(label.charAt(0))) {
label = label.toString().toUpperCase();
}
return label;
}

@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mKeyboard == null) {
setMeasuredDimension(mPaddingLeft + mPaddingRight, mPaddingTop + mPaddingBottom);
} else {
int width = mKeyboard.getMinWidth() + mPaddingLeft + mPaddingRight;
if (MeasureSpec.getSize(widthMeasureSpec) < width + 10) {
width = MeasureSpec.getSize(widthMeasureSpec);
}
setMeasuredDimension(width, mKeyboard.getHeight() + mPaddingTop + mPaddingBottom);
}
}

/**
* Compute the average distance between adjacent keys (horizontally and vertically)
* and square it to get the proximity threshold. We use a square here and in computing
* the touch distance from a key's center to avoid taking a square root.
* @param keyboard
*/
private void computeProximityThreshold(Keyboard keyboard) {
if (keyboard == null) return;
final Key[] keys = mKeys;
if (keys == null) return;
int length = keys.length;
int dimensionSum = 0;
for (int i = 0; i < length; i++) {
Key key = keys[i];
dimensionSum += Math.min(key.width, key.height) + key.gap;
}
if (dimensionSum < 0 || length == 0) return;
mProximityThreshold = (int) (dimensionSum * 1.4f / length);
mProximityThreshold *= mProximityThreshold;
}

@Override
public void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mBuffer = null;
}

@Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (mDrawPending || mBuffer == null || mKeyboardChanged) {
onBufferDraw();
}
canvas.drawBitmap(mBuffer, 0, 0, null);
}

private void onBufferDraw() {
boolean isBufferNull = (mBuffer == null);
if (isBufferNull || mKeyboardChanged) {
if (isBufferNull || mKeyboardChanged &&
(mBuffer.getWidth() != getWidth() || mBuffer.getHeight() != getHeight())) {
final int width = Math.max(1, getWidth());
final int height = Math.max(1, getHeight());
mBuffer = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBuffer);
}
invalidateAllKeys();
mKeyboardChanged = false;
}
final Canvas canvas = mCanvas;
canvas.clipRect(mDirtyRect, Op.REPLACE);

if (mKeyboard == null) return;

final Paint paint = mPaint;
final Rect clipRegion = mClipRegion;
final Rect padding = mPadding;
final int kbdPaddingLeft = mPaddingLeft;
final int kbdPaddingTop = mPaddingTop;
final Key[] keys = mKeys;
final Key invalidKey = mInvalidatedKey;

paint.setColor(mKeyTextColor);
boolean drawSingleKey = false;
if (invalidKey != null && canvas.getClipBounds(clipRegion)) {
if (invalidKey.x + kbdPaddingLeft - 1 <= clipRegion.left &&
invalidKey.y + kbdPaddingTop - 1 <= clipRegion.top &&
invalidKey.x + invalidKey.width + kbdPaddingLeft + 1 >= clipRegion.right &&
invalidKey.y + invalidKey.height + kbdPaddingTop + 1 >= clipRegion.bottom) {
drawSingleKey = true;
}
}
canvas.drawColor(0x00000000, PorterDuff.Mode.CLEAR);
final int keyCount = keys.length;
for (int i = 0; i < keyCount; i++) {
final Key key = keys[i];
if (drawSingleKey && invalidKey != key) {
continue;
}

paint.setColor(key.isSecondKey ? mKeyTextColor2nd : mKeyTextColor);
Drawable keyBackground = key.isSecondKey ? mKeyBackground2nd : mKeyBackground;
int[] drawableState = key.getCurrentDrawableState();
keyBackground.setState(drawableState);

String label = key.label == null? null : adjustCase(key.label).toString();

final Rect bounds = keyBackground.getBounds();
if (key.width != bounds.right ||
key.height != bounds.bottom) {
keyBackground.setBounds(0, 0, key.width, key.height);
}
canvas.translate(key.x + kbdPaddingLeft, key.y + kbdPaddingTop);
keyBackground.draw(canvas);

if (label != null) {
if (OpenWnn.isXLarge()) {
if (label.length() > 1 && key.codes.length < 2) {
paint.setTextSize(mLabelTextSize);
paint.setTypeface(Typeface.DEFAULT);
} else {
paint.setTextSize(mKeyTextSize);
paint.setTypeface(Typeface.DEFAULT_BOLD);
}
} else {
if (label.length() > 1 && key.codes.length < 2) {
paint.setTextSize(mLabelTextSize);
paint.setTypeface(Typeface.DEFAULT_BOLD);
} else {
paint.setTextSize(mKeyTextSize);
paint.setTypeface(Typeface.DEFAULT_BOLD);
}
}
paint.setShadowLayer(mShadowRadius, 0, 0, mShadowColor);
if (OpenWnn.isXLarge()) {
canvas.drawText(label,
(key.width - padding.left + 7 - padding.right) / 2
+ padding.left,
(key.height - padding.top + 7 - padding.bottom) / 2
+ (paint.getTextSize() - paint.descent()) / 2 + padding.top,
paint);
} else {
canvas.drawText(label,
(key.width - padding.left - padding.right) / 2
+ padding.left,
(key.height - padding.top - padding.bottom) / 2
+ (paint.getTextSize() - paint.descent()) / 2 + padding.top,
paint);
}
paint.setShadowLayer(0, 0, 0, 0);
} else if (key.icon != null) {
int drawableX;
int drawableY;
if (OpenWnn.isXLarge()) {
drawableX = (key.width - padding.left + 12 - padding.right
- key.icon.getIntrinsicWidth()) / 2 + padding.left;
drawableY = (key.height - padding.top + 9 - padding.bottom
- key.icon.getIntrinsicHeight()) / 2 + padding.top;
} else {
drawableX = (key.width - padding.left - padding.right
- key.icon.getIntrinsicWidth()) / 2 + padding.left;
drawableY = (key.height - padding.top - padding.bottom
- key.icon.getIntrinsicHeight()) / 2 + padding.top;
}
canvas.translate(drawableX, drawableY);
key.icon.setBounds(0, 0,
key.icon.getIntrinsicWidth(), key.icon.getIntrinsicHeight());
key.icon.draw(canvas);
canvas.translate(-drawableX, -drawableY);
}
canvas.translate(-key.x - kbdPaddingLeft, -key.y - kbdPaddingTop);
}
mInvalidatedKey = null;
if (mMiniKeyboardOnScreen) {
paint.setColor((int) (mBackgroundDimAmount * 0xFF) << 24);
canvas.drawRect(0, 0, getWidth(), getHeight(), paint);
}

mDrawPending = false;
mDirtyRect.setEmpty();
}

private int getKeyIndices(int x, int y, int[] allKeys) {
final Key[] keys = mKeys;
int primaryIndex = NOT_A_KEY;
int closestKey = NOT_A_KEY;
int closestKeyDist = mProximityThreshold + 1;
java.util.Arrays.fill(mDistances, Integer.MAX_VALUE);
int [] nearestKeyIndices = mKeyboard.getNearestKeys(x, y);
final int keyCount = nearestKeyIndices.length;
for (int i = 0; i < keyCount; i++) {
final Key key = keys[nearestKeyIndices[i]];
int dist = 0;
boolean isInside = key.isInside(x,y);
if (isInside) {
primaryIndex = nearestKeyIndices[i];
}

if (((mProximityCorrectOn
&& (dist = key.squaredDistanceFrom(x, y)) < mProximityThreshold)
|| isInside)
&& key.codes[0] > 32) {
final int nCodes = key.codes.length;
if (dist < closestKeyDist) {
closestKeyDist = dist;
closestKey = nearestKeyIndices[i];
}

if (allKeys == null) continue;

for (int j = 0; j < mDistances.length; j++) {
if (mDistances[j] > dist) {
System.arraycopy(mDistances, j, mDistances, j + nCodes,
mDistances.length - j - nCodes);
System.arraycopy(allKeys, j, allKeys, j + nCodes,
allKeys.length - j - nCodes);
for (int c = 0; c < nCodes; c++) {
allKeys[j + c] = key.codes[c];
mDistances[j + c] = dist;
}
break;
}
}
}
}
if (primaryIndex == NOT_A_KEY) {
primaryIndex = closestKey;
}
return primaryIndex;
}

private void detectAndSendKey(int index, int x, int y, long eventTime) {
if (index != NOT_A_KEY && index < mKeys.length) {
final Key key = mKeys[index];
if (key.text != null) {
mKeyboardActionListener.onText(key.text);
mKeyboardActionListener.onRelease(NOT_A_KEY);
} else {
int code = key.codes[0];
int[] codes = new int[MAX_NEARBY_KEYS];
Arrays.fill(codes, NOT_A_KEY);
getKeyIndices(x, y, codes);
if (mInMultiTap) {
if (mTapCount != -1) {
mKeyboardActionListener.onKey(Keyboard.KEYCODE_DELETE, KEY_DELETE);
} else {
mTapCount = 0;
}
code = key.codes[mTapCount];
}
mKeyboardActionListener.onKey(code, codes);
mKeyboardActionListener.onRelease(code);
}
mLastSentIndex = index;
mLastTapTime = eventTime;
}
}

/**
* Handle multi-tap keys by producing the key label for the current multi-tap state.
*/
private CharSequence getPreviewText(Key key) {
if (mInMultiTap) {
mPreviewLabel.setLength(0);
mPreviewLabel.append((char) key.codes[mTapCount < 0 ? 0 : mTapCount]);
return adjustCase(mPreviewLabel);
} else {
return adjustCase(key.label);
}
}

private void showPreview(int keyIndex) {
int oldKeyIndex = mCurrentKeyIndex;
final PopupWindow previewPopup = mPreviewPopup;

mCurrentKeyIndex = keyIndex;
final Key[] keys = mKeys;
if (oldKeyIndex != mCurrentKeyIndex) {
if (oldKeyIndex != NOT_A_KEY && keys.length > oldKeyIndex) {
keys[oldKeyIndex].onReleased(mCurrentKeyIndex == NOT_A_KEY);
invalidateKey(oldKeyIndex);
}
if (mCurrentKeyIndex != NOT_A_KEY && keys.length > mCurrentKeyIndex) {
keys[mCurrentKeyIndex].onPressed();
invalidateKey(mCurrentKeyIndex);
}
}
if (oldKeyIndex != mCurrentKeyIndex && mShowPreview && isParentPreviewEnabled()) {
mHandler.removeMessages(MSG_SHOW_PREVIEW);
if (previewPopup.isShowing()) {
if (keyIndex == NOT_A_KEY) {
mHandler.sendMessageDelayed(mHandler
.obtainMessage(MSG_REMOVE_PREVIEW),
DELAY_AFTER_PREVIEW);
}
}
if (keyIndex != NOT_A_KEY) {
if (previewPopup.isShowing() && mPreviewText.getVisibility() == VISIBLE) {
showKey(keyIndex);
} else {
mHandler.sendMessageDelayed(
mHandler.obtainMessage(MSG_SHOW_PREVIEW, keyIndex, 0),
DELAY_BEFORE_PREVIEW);
}
}
}
}

private void showKey(final int keyIndex) {
final PopupWindow previewPopup = mPreviewPopup;
final Key[] keys = mKeys;
if (keyIndex < 0 || keyIndex >= mKeys.length) return;
Key key = keys[keyIndex];

mPreviewText.setBackgroundDrawable(getContext().getResources().getDrawable(R.drawable.keyboard_key_feedback));

if (key.icon != null) {
mPreviewText.setCompoundDrawables(null, null, null,
key.iconPreview != null ? key.iconPreview : key.icon);
mPreviewText.setText(null);
mPreviewText.setPadding(5, 0, 5, 20);
} else {
mPreviewText.setCompoundDrawables(null, null, null, null);
mPreviewText.setText(getPreviewText(key));
if (key.label.length() > 1 && key.codes.length < 2) {
mPreviewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, mKeyTextSize);
mPreviewText.setTypeface(Typeface.DEFAULT_BOLD);
} else {
mPreviewText.setTextSize(TypedValue.COMPLEX_UNIT_PX, mPreviewTextSizeLarge);
mPreviewText.setTypeface(Typeface.DEFAULT);
}
mPreviewText.setPadding(0, 0, 0, 10);
}
mPreviewText.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int popupWidth = Math.max(mPreviewText.getMeasuredWidth(), key.width
+ mPreviewText.getPaddingLeft() + mPreviewText.getPaddingRight());
final int popupHeight = mPreviewHeight;
LayoutParams lp = mPreviewText.getLayoutParams();
if (lp != null) {
lp.width = popupWidth;
lp.height = popupHeight;
}
if (!mPreviewCentered) {
mPopupPreviewX = key.x - (Math.abs(popupWidth - key.width) / 2 );
mPopupPreviewY = key.y - popupHeight + mPreviewOffset;
} else {
mPopupPreviewX = 160 - mPreviewText.getMeasuredWidth() / 2;
mPopupPreviewY = - mPreviewText.getMeasuredHeight();
}
mPopupPreviewY = mPopupPreviewY + 20;
mHandler.removeMessages(MSG_REMOVE_PREVIEW);
if (mOffsetInWindow == null) {
mOffsetInWindow = new int[2];
getLocationInWindow(mOffsetInWindow);
mOffsetInWindow[0] += mMiniKeyboardOffsetX;
mOffsetInWindow[1] += mMiniKeyboardOffsetY;
int[] mWindowLocation = new int[2];
getLocationOnScreen(mWindowLocation);
mWindowY = mWindowLocation[1];
}
mPreviewText.getBackground().setState(
key.popupResId != 0 ? LONG_PRESSABLE_STATE_SET : EMPTY_STATE_SET);
mPopupPreviewX += mOffsetInWindow[0];
mPopupPreviewY += mOffsetInWindow[1];

if (mPopupPreviewY + mWindowY < 0) {
if (key.x + key.width <= getWidth() / 2) {
mPopupPreviewX += (int) (key.width * 2.5);
} else {
mPopupPreviewX -= (int) (key.width * 2.5);
}
mPopupPreviewY += popupHeight;
}

if (previewPopup.isShowing()) {
previewPopup.update(mPopupPreviewX, mPopupPreviewY,
popupWidth, popupHeight);
} else {
previewPopup.setWidth(popupWidth);
previewPopup.setHeight(popupHeight);
previewPopup.showAtLocation(mPopupParent, Gravity.NO_GRAVITY,
mPopupPreviewX, mPopupPreviewY);
}
mPreviewText.setVisibility(VISIBLE);
}

/**
* Requests a redraw of the entire keyboard. Calling {@link #invalidate} is not sufficient
* because the keyboard renders the keys to an off-screen buffer and an invalidate() only
* draws the cached buffer.
* @see #invalidateKey(int)
*/
public void invalidateAllKeys() {
mDirtyRect.union(0, 0, getWidth(), getHeight());
mDrawPending = true;
invalidate();
}

/**
* Invalidates a key so that it will be redrawn on the next repaint. Use this method if only
* one key is changing it's content. Any changes that affect the position or size of the key
* may not be honored.
* @param keyIndex the index of the key in the attached {@link Keyboard}.
* @see #invalidateAllKeys
*/
public void invalidateKey(int keyIndex) {
if (mKeys == null) return;
if (keyIndex < 0 || keyIndex >= mKeys.length) {
return;
}
final Key key = mKeys[keyIndex];
mInvalidatedKey = key;
mDirtyRect.union(key.x + mPaddingLeft, key.y + mPaddingTop,
key.x + key.width + mPaddingLeft, key.y + key.height + mPaddingTop);
onBufferDraw();
invalidate(key.x + mPaddingLeft, key.y + mPaddingTop,
key.x + key.width + mPaddingLeft, key.y + key.height + mPaddingTop);
}

private boolean openPopupIfRequired(MotionEvent me) {
if (mPopupLayout == 0) {
return false;
}
if (mCurrentKey < 0 || mCurrentKey >= mKeys.length) {
return false;
}

Key popupKey = mKeys[mCurrentKey];
boolean result = onLongPress(popupKey);
if (result) {
mAbortKey = true;
showPreview(NOT_A_KEY);
}
return result;
}

/**
* Called when a key is long pressed. By default this will open any popup keyboard associated
* with this key through the attributes popupLayout and popupCharacters.
* @param popupKey the key that was long pressed
* @return true if the long press is handled, false otherwise. Subclasses should call the
* method on the base class if the subclass doesn't wish to handle the call.
*/
protected boolean onLongPress(Key popupKey) {
if (mKeyboardActionListener.onLongPress(popupKey)) {
return true;
}
int popupKeyboardId = popupKey.popupResId;
if (popupKeyboardId != 0) {
mMiniKeyboardContainer = mMiniKeyboardCache.get(popupKey);
if (mMiniKeyboardContainer == null) {
LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(
Context.LAYOUT_INFLATER_SERVICE);
mMiniKeyboardContainer = inflater.inflate(mPopupLayout, null);
mMiniKeyboard = (KeyboardView) mMiniKeyboardContainer.findViewById(R.id.keyboardView);
View closeButton = mMiniKeyboardContainer.findViewById(R.id.closeButton);
if (closeButton != null) closeButton.setOnClickListener(this);
mMiniKeyboard.setOnKeyboardActionListener(new OnKeyboardActionListener() {
public void onKey(int primaryCode, int[] keyCodes) {
mKeyboardActionListener.onKey(primaryCode, keyCodes);
dismissPopupKeyboard();
}

public void onText(CharSequence text) {
mKeyboardActionListener.onText(text);
dismissPopupKeyboard();
}

public void swipeLeft() { }
public void swipeRight() { }
public void swipeUp() { }
public void swipeDown() { }
public void onPress(int primaryCode) {
mKeyboardActionListener.onPress(primaryCode);
}
public void onRelease(int primaryCode) {
mKeyboardActionListener.onRelease(primaryCode);
}
public boolean onLongPress(Keyboard.Key key) {
return false;
}
});
Keyboard keyboard;
if (popupKey.popupCharacters != null) {
keyboard = new Keyboard(getContext(), popupKeyboardId,
popupKey.popupCharacters, -1, getPaddingLeft() + getPaddingRight());
} else {
keyboard = new Keyboard(getContext(), popupKeyboardId);
}
mMiniKeyboard.setKeyboard(keyboard);
mMiniKeyboard.setPopupParent(this);
mMiniKeyboardContainer.measure(
MeasureSpec.makeMeasureSpec(getWidth(), MeasureSpec.AT_MOST),
MeasureSpec.makeMeasureSpec(getHeight(), MeasureSpec.AT_MOST));

mMiniKeyboardCache.put(popupKey, mMiniKeyboardContainer);
} else {
mMiniKeyboard = (KeyboardView) mMiniKeyboardContainer.findViewById(R.id.keyboardView);
}
if (mWindowOffset == null) {
mWindowOffset = new int[2];
getLocationInWindow(mWindowOffset);
}
mPopupX = popupKey.x + mPaddingLeft;
mPopupY = popupKey.y + mPaddingTop;
mPopupX = mPopupX + popupKey.width - mMiniKeyboardContainer.getMeasuredWidth();
mPopupY = mPopupY - mMiniKeyboardContainer.getMeasuredHeight();
final int x = mPopupX + mMiniKeyboardContainer.getPaddingRight() + mWindowOffset[0];
final int y = mPopupY + mMiniKeyboardContainer.getPaddingBottom() + mWindowOffset[1];
mMiniKeyboard.setPopupOffset(x < 0 ? 0 : x, y);
mMiniKeyboard.setShifted(isShifted());
mPopupKeyboard.setContentView(mMiniKeyboardContainer);
mPopupKeyboard.setWidth(mMiniKeyboardContainer.getMeasuredWidth());
mPopupKeyboard.setHeight(mMiniKeyboardContainer.getMeasuredHeight());
mPopupKeyboard.showAtLocation(this, Gravity.NO_GRAVITY, x, y);
mMiniKeyboardOnScreen = true;
invalidateAllKeys();
return true;
}
return false;
}

private long mOldEventTime;
private boolean mUsedVelocity;

@Override
public boolean onTouchEvent(MotionEvent me) {
final int pointerCount = me.getPointerCount();
final int action = me.getAction();
boolean result = false;
final long now = me.getEventTime();
final boolean isPointerCountOne = (pointerCount == 1);

if (pointerCount != mOldPointerCount) {
if (isPointerCountOne) {
MotionEvent down = MotionEvent.obtain(now, now, MotionEvent.ACTION_DOWN,
me.getX(), me.getY(), me.getMetaState());
result = onModifiedTouchEvent(down, false);
down.recycle();
if (action == MotionEvent.ACTION_UP) {
result = onModifiedTouchEvent(me, true);
}
} else {
MotionEvent up = MotionEvent.obtain(now, now, MotionEvent.ACTION_UP,
mOldPointerX, mOldPointerY, me.getMetaState());
result = onModifiedTouchEvent(up, true);
up.recycle();
}
} else {
if (isPointerCountOne) {
result = onModifiedTouchEvent(me, false);
mOldPointerX = me.getX();
mOldPointerY = me.getY();
} else {
result = true;
}
}
mOldPointerCount = pointerCount;

return result;
}

private boolean onModifiedTouchEvent(MotionEvent me, boolean possiblePoly) {
int touchX = (int) me.getX() - mPaddingLeft;
int touchY = (int) me.getY() + mVerticalCorrection - mPaddingTop;
final int action = me.getAction();
final long eventTime = me.getEventTime();
mOldEventTime = eventTime;
int keyIndex = getKeyIndices(touchX, touchY, null);
mPossiblePoly = possiblePoly;

if (action == MotionEvent.ACTION_DOWN) mSwipeTracker.clear();
mSwipeTracker.addMovement(me);

if (mAbortKey
&& action != MotionEvent.ACTION_DOWN && action != MotionEvent.ACTION_CANCEL) {
return true;
}

if (mGestureDetector.onTouchEvent(me)) {
showPreview(NOT_A_KEY);
mHandler.removeMessages(MSG_REPEAT);
mHandler.removeMessages(MSG_LONGPRESS);
return true;
}

if (mMiniKeyboardOnScreen && action != MotionEvent.ACTION_CANCEL) {
return true;
}

switch (action) {
case MotionEvent.ACTION_DOWN:
mAbortKey = false;
mStartX = touchX;
mStartY = touchY;
mLastCodeX = touchX;
mLastCodeY = touchY;
mLastKeyTime = 0;
mCurrentKeyTime = 0;
mLastKey = NOT_A_KEY;
mCurrentKey = keyIndex;
mDownKey = keyIndex;
mDownTime = me.getEventTime();
mLastMoveTime = mDownTime;
checkMultiTap(eventTime, keyIndex);
mKeyboardActionListener.onPress(keyIndex != NOT_A_KEY ?
mKeys[keyIndex].codes[0] : 0);
if (mCurrentKey >= 0 && mKeys[mCurrentKey].repeatable) {
mRepeatKeyIndex = mCurrentKey;
Message msg = mHandler.obtainMessage(MSG_REPEAT);
mHandler.sendMessageDelayed(msg, REPEAT_START_DELAY);
repeatKey();
if (mAbortKey) {
mRepeatKeyIndex = NOT_A_KEY;
break;
}
}
if (mCurrentKey != NOT_A_KEY) {
Message msg = mHandler.obtainMessage(MSG_LONGPRESS, me);
mHandler.sendMessageDelayed(msg, LONGPRESS_TIMEOUT);
}
showPreview(keyIndex);
break;

case MotionEvent.ACTION_MOVE:
boolean continueLongPress = false;
if (keyIndex != NOT_A_KEY) {
if (mCurrentKey == NOT_A_KEY) {
mCurrentKey = keyIndex;
mCurrentKeyTime = eventTime - mDownTime;
} else {
if (keyIndex == mCurrentKey) {
mCurrentKeyTime += eventTime - mLastMoveTime;
continueLongPress = true;
} else if (mRepeatKeyIndex == NOT_A_KEY) {
resetMultiTap();
mLastKey = mCurrentKey;
mLastCodeX = mLastX;
mLastCodeY = mLastY;
mLastKeyTime =
mCurrentKeyTime + eventTime - mLastMoveTime;
mCurrentKey = keyIndex;
mCurrentKeyTime = 0;
}
}
}
if (!continueLongPress) {
mHandler.removeMessages(MSG_LONGPRESS);
if (keyIndex != NOT_A_KEY) {
Message msg = mHandler.obtainMessage(MSG_LONGPRESS, me);
mHandler.sendMessageDelayed(msg, LONGPRESS_TIMEOUT);
}
}
showPreview(mCurrentKey);
mLastMoveTime = eventTime;
break;

case MotionEvent.ACTION_UP:
removeMessages();
if (keyIndex == mCurrentKey) {
mCurrentKeyTime += eventTime - mLastMoveTime;
} else {
resetMultiTap();
mLastKey = mCurrentKey;
mLastKeyTime = mCurrentKeyTime + eventTime - mLastMoveTime;
mCurrentKey = keyIndex;
mCurrentKeyTime = 0;
}
if (mCurrentKeyTime < mLastKeyTime && mCurrentKeyTime < DEBOUNCE_TIME
&& mLastKey != NOT_A_KEY) {
mCurrentKey = mLastKey;
touchX = mLastCodeX;
touchY = mLastCodeY;
}
showPreview(NOT_A_KEY);
Arrays.fill(mKeyIndices, NOT_A_KEY);
if (mRepeatKeyIndex == NOT_A_KEY && !mMiniKeyboardOnScreen && !mAbortKey) {
detectAndSendKey(mCurrentKey, touchX, touchY, eventTime);
}
invalidateKey(keyIndex);
mRepeatKeyIndex = NOT_A_KEY;
break;
case MotionEvent.ACTION_CANCEL:
removeMessages();
dismissPopupKeyboard();
mAbortKey = true;
showPreview(NOT_A_KEY);
invalidateKey(mCurrentKey);
break;
}
mLastX = touchX;
mLastY = touchY;
return true;
}

private boolean repeatKey() {
Key key = mKeys[mRepeatKeyIndex];
detectAndSendKey(mCurrentKey, key.x, key.y, mLastTapTime);
return true;
}

protected void swipeRight() {
mKeyboardActionListener.swipeRight();
}

protected void swipeLeft() {
mKeyboardActionListener.swipeLeft();
}

protected void swipeUp() {
mKeyboardActionListener.swipeUp();
}

protected void swipeDown() {
mKeyboardActionListener.swipeDown();
}

public void closing() {
if (mPreviewPopup.isShowing()) {
mPreviewPopup.dismiss();
}
removeMessages();

dismissPopupKeyboard();
mBuffer = null;
mCanvas = null;
mMiniKeyboardCache.clear();
}

private void removeMessages() {
mHandler.removeMessages(MSG_REPEAT);
mHandler.removeMessages(MSG_LONGPRESS);
mHandler.removeMessages(MSG_SHOW_PREVIEW);
}

@Override
public void onDetachedFromWindow() {
super.onDetachedFromWindow();
closing();
}

private void dismissPopupKeyboard() {
if (mPopupKeyboard.isShowing()) {
mPopupKeyboard.dismiss();
mMiniKeyboardOnScreen = false;
invalidateAllKeys();
}
}

public boolean handleBack() {
if (mPopupKeyboard.isShowing()) {
dismissPopupKeyboard();
return true;
}
return false;
}

private void resetMultiTap() {
mLastSentIndex = NOT_A_KEY;
mTapCount = 0;
mLastTapTime = -1;
mInMultiTap = false;
}

private void checkMultiTap(long eventTime, int keyIndex) {
if (keyIndex == NOT_A_KEY) return;
Key key = mKeys[keyIndex];
if (key.codes.length > 1) {
mInMultiTap = true;
if (eventTime < mLastTapTime + MULTITAP_INTERVAL
&& keyIndex == mLastSentIndex) {
mTapCount = (mTapCount + 1) % key.codes.length;
return;
} else {
mTapCount = -1;
return;
}
}
if (eventTime > mLastTapTime + MULTITAP_INTERVAL || keyIndex != mLastSentIndex) {
resetMultiTap();
}
}

private static class SwipeTracker {

static final int NUM_PAST = 4;
static final int LONGEST_PAST_TIME = 200;

final float mPastX[] = new float[NUM_PAST];
final float mPastY[] = new float[NUM_PAST];
final long mPastTime[] = new long[NUM_PAST];

float mYVelocity;
float mXVelocity;

public void clear() {
mPastTime[0] = 0;
}

public void addMovement(MotionEvent ev) {
long time = ev.getEventTime();
final int N = ev.getHistorySize();
for (int i=0; i<N; i++) {
addPoint(ev.getHistoricalX(i), ev.getHistoricalY(i),
ev.getHistoricalEventTime(i));
}
addPoint(ev.getX(), ev.getY(), time);
}

private void addPoint(float x, float y, long time) {
int drop = -1;
int i;
final long[] pastTime = mPastTime;
for (i=0; i<NUM_PAST; i++) {
if (pastTime[i] == 0) {
break;
} else if (pastTime[i] < time-LONGEST_PAST_TIME) {
drop = i;
}
}
if (i == NUM_PAST && drop < 0) {
drop = 0;
}
if (drop == i) drop--;
final float[] pastX = mPastX;
final float[] pastY = mPastY;
if (drop >= 0) {
final int start = drop+1;
final int count = NUM_PAST-drop-1;
System.arraycopy(pastX, start, pastX, 0, count);
System.arraycopy(pastY, start, pastY, 0, count);
System.arraycopy(pastTime, start, pastTime, 0, count);
i -= (drop+1);
}
pastX[i] = x;
pastY[i] = y;
pastTime[i] = time;
i++;
if (i < NUM_PAST) {
pastTime[i] = 0;
}
}

public void computeCurrentVelocity(int units) {
computeCurrentVelocity(units, Float.MAX_VALUE);
}

public void computeCurrentVelocity(int units, float maxVelocity) {
final float[] pastX = mPastX;
final float[] pastY = mPastY;
final long[] pastTime = mPastTime;

final float oldestX = pastX[0];
final float oldestY = pastY[0];
final long oldestTime = pastTime[0];
float accumX = 0;
float accumY = 0;
int N=0;
while (N < NUM_PAST) {
if (pastTime
== 0) {
break;
}
N++;
}

for (int i=1; i < N; i++) {
final int dur = (int)(pastTime[i] - oldestTime);
if (dur == 0) continue;
float dist = pastX[i] - oldestX;
float vel = (dist/dur) * units;
if (accumX == 0) accumX = vel;
else accumX = (accumX + vel) * .5f;

dist = pastY[i] - oldestY;
vel = (dist/dur) * units;
if (accumY == 0) accumY = vel;
else accumY = (accumY + vel) * .5f;
}
mXVelocity = accumX < 0.0f ? Math.max(accumX, -maxVelocity)
: Math.min(accumX, maxVelocity);
mYVelocity = accumY < 0.0f ? Math.max(accumY, -maxVelocity)
: Math.min(accumY, maxVelocity);
}

public float getXVelocity() {
return mXVelocity;
}

public float getYVelocity() {
return mYVelocity;
}
}

/**
* Clear window info.
*/
public void clearWindowInfo() {
mOffsetInWindow = null;
}
}

它里面有很多方法，在我们自定义的软键盘很多属性，就需要我们用这个类来设置比如：

keyboardView = (KeyboardView) act.findViewById(R.id.keyboard_view);  

keyboardView.setKeyboard(k);  

keyboardView.setEnabled(true);  

keyboardView.setPreviewEnabled(true);

keyboardView.setVisibility(View.VISIBLE);

keyboardView.setOnKeyboardActionListener(listener);

了解一些源码，就可以是我们知道我们为什么要这样写，为什么要这样做了！

我们还需要建一个xml文件，来布局我们的视图，一般是在res文件夹中建一个名为xml的文件夹，在里面新建立一个xml布局文件。

每一个按键的属性主要包括 android:codes=" " android:keyLabel=" "。activity就是根据codes的值来监听的。一些可以自定义设置，一些需要是keyboard中设置好的，要保持一致。

好了，今天就先说到这里，下次再继续说建立一个完整的项目实例的过程！