Android自定义View之数字密码锁

距上次写博客已经快一年了，计划赶不上变化，种种原因加上自己的拖延症= =、 之前想好的每月一文还是没能坚持下来，趁着闲暇之余撸一篇，希望之后能够继续坚持总结的习惯。最近项目上用到一个密码加锁功能，需要一个数字密码界面，就想着封装成一个View来方便管理和使用。

废话不多说，先上最终效果图：



思路

整体可分为2个部分来实现，1.顶部是4个密码位的填充；2.数字键盘部分。整体可以是一个纵向LinearLayout，4个密码位用横向LinearLayout即可，键盘由于是宫格形式，因此可用GridLayout来布局。由于密码位和键盘数字都是以圆圈为背景，这里采用自定义一个圆形背景ImageView来使用。

实现

1.页面布局

首先定义一个圆形背景的ImageView，由于最终实现的效果是点击的时候要填充圆背景，非点击状态下是空心圆，因此可通过改变Paint的style来动态更改显示:

/**
* 圆形背景ImageView（设置实心或空心）
*/
public class CircleImageView extends ImageView{

private Paint mPaint;
private int mWidth;
private int mHeight;

public CircleImageView(Context context) {
this(context, null);
}

public CircleImageView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

public CircleImageView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
initView(context);
}

public void initView(Context context){
mPaint = new Paint();
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(mPanelColor);
mPaint.setStrokeWidth(mStrokeWidth);
mPaint.setAntiAlias(true);
}

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mWidth = w;
mHeight = h;
}

@Override
public void draw(Canvas canvas) {
canvas.drawCircle(mWidth/2, mHeight/2, mWidth/2 - 6, mPaint);
super.draw(canvas);
}

/**
* 设置圆为实心状态
*/
public void setFillCircle(){
mPaint.setStyle(Paint.Style.FILL);
invalidate();
}

/**
* 设置圆为空心状态
*/
public void setStrokeCircle(){
mPaint.setStyle(Paint.Style.STROKE);
invalidate();
}
}

可以看到，在onDraw中绘制了一个圆，默认为空心状态，定义setFillCircle和setStrokeCircle这两个方法以便外界可以方便地切换圆为实心或者空心。

圆形ImageView定义好了，开始添加密码位，布局如下:

inputResultView = new LinearLayout(context);
for(int i=0; i<4; i++){
CircleImageView mResultItem = new CircleImageView(context);
mResultIvList.add(mResultItem);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(mResultIvRadius, mResultIvRadius);
params.leftMargin = dip2px(context, 4);
params.rightMargin = dip2px(context, 4);
mResultItem.setPadding(dip2px(context, 2),dip2px(context, 2),dip2px(context, 2),dip2px(context, 2));
mResultItem.setLayoutParams(params);
inputResultView.addView(mResultItem);
}
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
params.gravity = Gravity.CENTER_HORIZONTAL;
params.bottomMargin = dip2px(context, 34);
inputResultView.setLayoutParams(params);
addView(inputResultView);

接着添加数字键盘部分的布局:

GridLayout numContainer = new GridLayout(context);
numContainer.setColumnCount(3);
for(int i=0; i<numArr.length; i++){
RelativeLayout numItem = new RelativeLayout(context);
numItem.setPadding(mPaddingLeftRight,mPaddingTopBottom,mPaddingLeftRight,mPaddingTopBottom);
RelativeLayout.LayoutParams gridItemParams = new RelativeLayout.LayoutParams(mNumRadius, mNumRadius);
gridItemParams.addRule(CENTER_IN_PARENT);
final TextView numTv = new TextView(context);
numTv.setText(numArr[i]);
numTv.setTextColor(mPanelColor);
numTv.setTextSize(30);
numTv.setGravity(Gravity.CENTER);
numTv.setLayoutParams(gridItemParams);
final CircleImageView numBgIv = new CircleImageView(context);
numBgIv.setLayoutParams(gridItemParams);
numItem.addView(numBgIv);
numItem.addView(numTv);
numContainer.addView(numItem);
if(i == 9){
numItem.setVisibility(INVISIBLE);
}
}

//删除按钮
RelativeLayout deleteItem = new RelativeLayout(context);
deleteItem.setPadding(mPaddingLeftRight,mPaddingTopBottom,mPaddingLeftRight,mPaddingTopBottom);
RelativeLayout.LayoutParams gridItemParams = new RelativeLayout.LayoutParams(mNumRadius, mNumRadius);
gridItemParams.addRule(CENTER_IN_PARENT);
//假如删除按钮是设置自定义图片资源的话，可用注释这段
//ImageView deleteIv = new ImageView(context);
//deleteIv.setImageResource(R.drawable.icn_delete_pw);
//deleteIv.setLayoutParams(gridItemParams);
//deleteItem.addView(deleteIv);
TextView deleteTv = new TextView(context);
deleteTv.setText("Delete");
deleteTv.setTextColor(mPanelColor);
deleteTv.setTextSize(dip2px(context, 8));
deleteTv.setLayoutParams(gridItemParams);
deleteTv.setGravity(Gravity.CENTER);
deleteItem.addView(deleteTv);
numContainer.addView(deleteItem);

LinearLayout.LayoutParams gridParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
gridParams.gravity = Gravity.CENTER_HORIZONTAL;
numContainer.setLayoutParams(gridParams);
addView(numContainer);

数字键盘这里用一个数组存数字内容，遍历添加，注意此处由于第10个的子View的时候是空白的，所以当遍历到第10个元素的时候，可以将其隐藏。遍历完后再单独添加删除按钮。

2.输入逻辑

页面布局完成了，接下来就是密码输入的逻辑部分，最终的效果是每点击一次数字，密码位就填充一个，每点击删除按钮一次，密码位就回退一个，输入4个数字之后，即完成输入，获取结果，并重置密码位。这里用一个StringBuilder变量来记录当前已输入的密码，每次添加就append进去，每次删除就调用deleteCharAt。

由于点击数字按下的时候填充，松开的时候为空心状态，所以可以在ACTION_DOWN和ACTION_UP事件中分别操作:

numTv.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
numBgIv.setFillCircle();
numTv.setTextColor(Color.WHITE);
if(mPassWord.length() < 4){
mPassWord.append(numTv.getText());
mResultIvList.get(mPassWord.length()-1).setFillCircle();
if(mInputListener!=null && mPassWord.length() == 4){
//已完整输入4个
}
}
break;
case MotionEvent.ACTION_UP:
numBgIv.setStrokeCircle();
numTv.setTextColor(mPanelColor);
break;
}
return true;
}
});

每次点击的时候，判断当前已输入的密码位是否已经超过4位，如果没超过，就继续追加。如果等于4，就说明输入完成，此时的mPassWord的内容就是最终的密码，可以用一个接口将其回调出去方便Activity中获取输入的密码：

/**
* 监听输入完毕的接口
*/
private InputListener mInputListener;

public void setInputListener(InputListener mInputListener) {
his.mInputListener = mInputListener;
}

public interface InputListener{
void inputFinish(String result);
}

然后在上面的ACTION_DOWN中输入数字等于4的时候，回调该接口：

if(mInputListener!=null && mPassWord.length() == 4){
mInputListener.inputFinish(mPassWord.toString());
}

另外，删除的操作单独封装为一个方法：

/**
* 删除
*/
public void delete(){
if(mPassWord.length() == 0){
return;
}
mResultIvList.get(mPassWord.length()-1).setStrokeCircle();
mPassWord.deleteCharAt(mPassWord.length()-1);
}

注意点：当前无输入密码时，直接return不作任何操作，假如已有输入数字，就删除最尾部的那个数字。

最后，还要考虑一种情况，即用户输入密码错误时的一些反馈，参照平时的习惯，一般是4个密码位左右摆动并且手机震动效果，震动结束之后，当前存储的密码位重置为初始状态，如下：

/**
* 输入错误的状态显示(包括震动，密码位左右摇摆效果，重置密码位)
*/
public void showErrorStatus(){
mVibrator.vibrate(new long[]{100,100,100,100},-1);
List<Animator> animators = new ArrayList<>();
ObjectAnimator translationXAnim = ObjectAnimator.ofFloat(inputResultView, "translationX", -50.0f,50.0f,-50.0f,0.0f);
translationXAnim.setDuration(400);
animators.add(translationXAnim);
AnimatorSet btnSexAnimatorSet = new AnimatorSet();
btnSexAnimatorSet.playTogether(animators);
btnSexAnimatorSet.start();
btnSexAnimatorSet.addListener(new Animator.AnimatorListener() {
@Override
public void onAnimationStart(Animator animation) {

}

@Override
public void onAnimationEnd(Animator animation) {
resetResult();
}

@Override
public void onAnimationCancel(Animator animation) {

}

@Override
public void onAnimationRepeat(Animator animation) {

}
});
}

可以看到，在onAnimationEnd中调用了resetResult，即动画结束时重置密码，resetResult方法如下：

/**
* 重置密码输入
*/
public void resetResult(){
for(int i=0; i<mResultIvList.size(); i++){
mResultIvList.get(i).setStrokeCircle();
}
mPassWord.delete(0, 4);
}

遍历所有密码位View设置为空心，并且删除当前mPassWord变量存储的所有内容。

完整代码

完整的自定义数字密码锁代码如下：

package com.example.zjyang.viewtest.view;

import android.animation.Animator;
import android.animation.AnimatorSet;
import android.animation.ObjectAnimator;
import android.app.Service;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Vibrator;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.GridLayout;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

import static android.widget.RelativeLayout.CENTER_HORIZONTAL;
import static android.widget.RelativeLayout.CENTER_IN_PARENT;

/**
* Created by IT_ZJYANG on 2018/1/22.
* 数字解锁键盘View
*/

public class NumLockPanel extends LinearLayout {

private String[] numArr = new String[]{"1","2","3","4","5","6","7","8","9", "", "0"};

private int mPaddingLeftRight;
private int mPaddingTopBottom;
//4个密码位ImageView
private ArrayList<CircleImageView> mResultIvList;

private LinearLayout inputResultView;
//存储当前输入内容
private StringBuilder mPassWord;
//振动效果
private Vibrator mVibrator;
//整个键盘的颜色
private int mPanelColor;
//4个密码位的宽度
private int mResultIvRadius;
//数字键盘的每个圆的宽度
private int mNumRadius;
//每个圆的边界宽度
private int mStrokeWidth;

public NumLockPanel(Context context) {
this(context, null);
}

public NumLockPanel(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

public NumLockPanel(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
mPaddingLeftRight = dip2px(context, 21);
mPaddingTopBottom = dip2px(context, 10);
mPanelColor = Color.BLACK; //颜色代码可采用Color.parse("#000000");
mResultIvRadius = dip2px(context, 20);
mNumRadius = dip2px(context, 66);
mStrokeWidth = dip2px(context, 2);
mVibrator = (Vibrator)context.getSystemService(Service.VIBRATOR_SERVICE);
mResultIvList = new ArrayList<>();
mPassWord = new StringBuilder();
setOrientation(VERTICAL);
setGravity(CENTER_HORIZONTAL);
initView(context);
}

public void initView(Context context){
//4个结果号码
inputResultView = new LinearLayout(context);
for(int i=0; i<4; i++){
CircleImageView mResultItem = new CircleImageView(context);
mResultIvList.add(mResultItem);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(mResultIvRadius, mResultIvRadius);
params.leftMargin = dip2px(context, 4);
params.rightMargin = dip2px(context, 4);
mResultItem.setPadding(dip2px(context, 2),dip2px(context, 2),dip2px(context, 2),dip2px(context, 2));
mResultItem.setLayoutParams(params);
inputResultView.addView(mResultItem);
}
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
params.gravity = Gravity.CENTER_HORIZONTAL;
params.bottomMargin = dip2px(context, 34);
inputResultView.setLayoutParams(params);
addView(inputResultView);

//数字键盘
GridLayout numContainer = new GridLayout(context);
numContainer.setColumnCount(3);
for(int i=0; i<numArr.length; i++){
RelativeLayout numItem = new RelativeLayout(context);
numItem.setPadding(mPaddingLeftRight,mPaddingTopBottom,mPaddingLeftRight,mPaddingTopBottom);
RelativeLayout.LayoutParams gridItemParams = new RelativeLayout.LayoutParams(mNumRadius, mNumRadius);
gridItemParams.addRule(CENTER_IN_PARENT);
final TextView numTv = new TextView(context);
numTv.setText(numArr[i]);
numTv.setTextColor(mPanelColor);
numTv.setTextSize(30);
numTv.setGravity(Gravity.CENTER);
numTv.setLayoutParams(gridItemParams);
final CircleImageView numBgIv = new CircleImageView(context);
numBgIv.setLayoutParams(gridItemParams);
numTv.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
numBgIv.setFillCircle();
numTv.setTextColor(Color.WHITE);
if(mPassWord.length() < 4){
mPassWord.append(numTv.getText());
mResultIvList.get(mPassWord.length()-1).setFillCircle();
if(mInputListener!=null && mPassWord.length() == 4){
mInputListener.inputFinish(mPassWord.toString());
}
}
break;
case MotionEvent.ACTION_UP:
numBgIv.setStrokeCircle();
numTv.setTextColor(mPanelColor);
break;
}
return true;
}
});

numItem.addView(numBgIv);
numItem.addView(numTv);
numContainer.addView(numItem);
if(i == 9){
numItem.setVisibility(INVISIBLE);
}
}

//删除按钮
RelativeLayout deleteItem = new RelativeLayout(context);
deleteItem.setPadding(mPaddingLeftRight,mPaddingTopBottom,mPaddingLeftRight,mPaddingTopBottom);
RelativeLayout.LayoutParams gridItemParams = new RelativeLayout.LayoutParams(mNumRadius, mNumRadius);
gridItemParams.addRule(CENTER_IN_PARENT);
//假如删除按钮是设置自定义图片资源的话，可用注释这段
//ImageView deleteIv = new ImageView(context);
//deleteIv.setImageResource(R.drawable.icn_delete_pw);
//deleteIv.setLayoutParams(gridItemParams);
//deleteItem.addView(deleteIv);
TextView deleteTv = new TextView(context);
deleteTv.setText("Delete");
deleteTv.setTextColor(mPanelColor);
deleteTv.setTextSize(dip2px(context, 8));
deleteTv.setLayoutParams(gridItemParams);
deleteTv.setGravity(Gravity.CENTER);
deleteItem.addView(deleteTv);
numContainer.addView(deleteItem);
deleteTv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
delete();
}
});

LinearLayout.LayoutParams gridParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
gridParams.gravity = Gravity.CENTER_HORIZONTAL;
numContainer.setLayoutParams(gridParams);
addView(numContainer);
}

/**
* 输入错误的状态显示(包括震动，密码位左右摇摆效果，重置密码位)
*/
public void showErrorStatus(){
mVibrator.vibrate(new long[]{100,100,100,100},-1);
List<Animator> animators = new ArrayList<>();
ObjectAnimator translationXAnim = ObjectAnimator.ofFloat(inputResultView, "translationX", -50.0f,50.0f,-50.0f,0.0f);
translationXAnim.setDuration(400);
animators.add(translationXAnim);
AnimatorSet btnSexAnimatorSet = new AnimatorSet();
btnSexAnimatorSet.playTogether(animators);
btnSexAnimatorSet.start();
btnSexAnimatorSet.addListener(new Animator.AnimatorListener() {
@Override
public void onAnimationStart(Animator animation) {

}

@Override
public void onAnimationEnd(Animator animation) {
resetResult();
}

@Override
public void onAnimationCancel(Animator animation) {

}

@Override
public void onAnimationRepeat(Animator animation) {

}
});
}

/**
* 删除
*/
public void delete(){
if(mPassWord.length() == 0){
return;
}
mResultIvList.get(mPassWord.length()-1).setStrokeCircle();
mPassWord.deleteCharAt(mPassWord.length()-1);
}

/**
* 重置密码输入
*/
public void resetResult(){
for(int i=0; i<mResultIvList.size(); i++){
mResultIvList.get(i).setStrokeCircle();
}
mPassWord.delete(0, 4);
}

/**
* 监听输入完毕的接口
*/
private InputListener mInputListener;

public void setInputListener(InputListener mInputListener) {
this.mInputListener = mInputListener;
}

public interface InputListener{
void inputFinish(String result);
}

/**
* dip/dp转像素
*
* @param dipValue
*            dip或 dp大小
* @return 像素值
*/
public static int dip2px(Context context, float dipValue) {
DisplayMetrics metrics = context.getResources().getDisplayMetrics();
return (int) (dipValue * (metrics.density) + 0.5f);
}

/**
* 圆形背景ImageView（设置实心或空心）
*/
public class CircleImageView extends ImageView{

private Paint mPaint;
private int mWidth;
private int mHeight;

public CircleImageView(Context context) {
this(context, null);
}

public CircleImageView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

public CircleImageView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
initView(context);
}

public void initView(Context context){
mPaint = new Paint();
mPaint.setStyle(Paint.Style.STROKE);
mPaint.setColor(mPanelColor);
mPaint.setStrokeWidth(mStrokeWidth);
mPaint.setAntiAlias(true);
}

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mWidth = w;
mHeight = h;
}

@Override
public void draw(Canvas canvas) {
canvas.drawCircle(mWidth/2, mHeight/2, mWidth/2 - 6, mPaint);
super.draw(canvas);
}

/**
* 设置圆为实心状态
*/
public void setFillCircle(){
mPaint.setStyle(Paint.Style.FILL);
invalidate();
}

/**
* 设置圆为空心状态
*/
public void setStrokeCircle(){
mPaint.setStyle(Paint.Style.STROKE);
invalidate();
}
}
}

使用

在Activity的布局文件中：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff"
tools:context="com.example.zjyang.viewtest.MainActivity">

<com.example.zjyang.viewtest.view.NumLockPanel
android:id="@+id/num_lock"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="30dp">

</com.example.zjyang.viewtest.view.NumLockPanel>
</RelativeLayout>

在代码中监听输入的密码结果：

public class MainActivity extends AppCompatActivity {

private NumLockPanel mNumLockPanel;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

mNumLockPanel = (NumLockPanel) findViewById(R.id.num_lock);
mNumLockPanel.setInputListener(new NumLockPanel.InputListener() {
@Override
public void inputFinish(String result) {
//此处result即为输入结果
Toast.makeText(MainActivity.this, result, Toast.LENGTH_SHORT).show();
//错误效果示例
mNumLockPanel.showErrorStatus();
}
});
}
}

最后，在自定义View构造方法中初始化了圆圆和数字的颜色风格，以及空心圆的边界粗细大小，可根据需求自行更改。