自定义view例子（【图片移动】【仿联系人边上字母列表】）

图片移动代码

[code]<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
   <com.example.administrator.mywidgetmode.Bitmapview.MyBitmapView
       android:layout_width="match_parent"
       android:layout_height="match_parent" />
</LinearLayout>

[code]package com.example.administrator.mywidgetmode.Bitmapview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.example.administrator.mywidgetmode.R;

/**
 * Created by Administrator on 2015/9/17.
 */
public class MyBitmapViewActivity extends AppCompatActivity{
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_bitmap);
    }
}

[code]package com.example.administrator.mywidgetmode.Bitmapview;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;

import com.example.administrator.mywidgetmode.R;

/**
 * Created by Administrator on 2015/9/17.
 */
public class MyBitmapView extends View {
    private int width;
    private int height;
    private Bitmap mBitmap;
    private Paint mPaint;
    private Matrix matrix;
    private int mBitmapWidth;
    private int mBitmapHeight;

    public MyBitmapView(Context context) {
        super(context);
    }

    public MyBitmapView(Context context, AttributeSet attrs) {
        super(context, attrs);
        mBitmap = BitmapFactory.decodeResource(getResources(), R.mipmap.b);
        Log.d("bitmap", "图片相关信息高" + mBitmap.getWidth() + "宽" + mBitmap.getHeight());
        mPaint = new Paint();
        matrix = new Matrix();
        mBitmapWidth = mBitmap.getWidth();
        mBitmapHeight = mBitmap.getHeight();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        width = getDefaultSize(getSuggestedMinimumWidth(), widthMeasureSpec);
        height = getDefaultSize(getSuggestedMinimumHeight(), heightMeasureSpec);
        setMeasuredDimension(width, height);//设置画布的大小，长和宽
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        //缩放
        matrix.reset();
        matrix.postScale(2, 2);//高放大两倍，宽放大两倍
        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //原图
        matrix.reset();
        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //y轴平移两个高
        matrix.postTranslate(0, mBitmapHeight * 2);
        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //旋转
        matrix.reset();
        matrix.postRotate(180);//旋转角度
        matrix.postTranslate(mBitmapWidth * 2, mBitmapHeight * 3);//平移
        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //拉伸
//        matrix.reset();
//        matrix.postSkew(0, 2);
//        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //关于x轴对称
        matrix.reset();
        float matrix_values[] = {1f, 0f, 0f, 0f, -1f, 0f, 0f, 0f, 1f};
        matrix.setValues(matrix_values);
        matrix.postTranslate(0, mBitmapHeight * 2);
        canvas.drawBitmap(mBitmap, matrix, mPaint);
        //关于y轴对称
        matrix.reset();
        float matrix_values2[] = {-1f, 0f, 0f, 0f, 1f, 0f, 0f, 0f, 1f};
        matrix.setValues(matrix_values2);
        matrix.postTranslate(mBitmapWidth * 2, 0);
        canvas.drawBitmap(mBitmap, matrix, mPaint);

    }
}

仿联系人边上字母列表代码

[code]<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    <com.example.administrator.mywidgetmode.Slider.MySlider
        android:id="@+id/myslider"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
    <TextView
        android:id="@+id/textview"
        android:text="A"
        android:textSize="100dp"
        android:gravity="center"
        android:layout_width="200dp"
        android:layout_height="200dp"
        android:layout_centerInParent="true"/>
</RelativeLayout>

[code]package com.example.administrator.mywidgetmode.Slider;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.PersistableBundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.Button;
import android.widget.TextView;

import com.example.administrator.mywidgetmode.R;

/**
 * Created by Administrator on 2015/9/17.
 */
public class MySliderActivity extends AppCompatActivity {
    private TextView mTextView;
    private MySlider mySlider;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_slider);
        mTextView = (TextView) findViewById(R.id.textview);
        mySlider = (MySlider) findViewById(R.id.myslider);
        mySlider.setonItemSelectedListener(new MySlider.OnItemSelect() {
            @Override
            public void onItemSelected(int index, String indexString) {
               mTextView.setText(indexString);
            }
        });
    }
}

[code]package com.example.administrator.mywidgetmode.Slider;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

/**
 * Created by Administrator on 2015/9/17.
 */
public class MySlider extends View {
    private int width;
    private int height;
    private Paint mPaintText;
    private Paint mPaintRed;
    private int index=-1;
    private String[] array = {"a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"};
    //观察者模式
    private OnItemSelect listener;
    public  interface OnItemSelect{
        public void onItemSelected(int index,String indexString);
    }

    public void setonItemSelectedListener(OnItemSelect listener) {
        this.listener = listener;
    }

    public MySlider(Context context) {
        super(context);
    }

    public MySlider(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaintText = new Paint();
        mPaintText.setTextAlign(Paint.Align.CENTER);

        mPaintRed=new Paint();
        mPaintRed.setColor(Color.RED);
        mPaintRed.setTextAlign(Paint.Align.CENTER);

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        width = getDefaultSize(getSuggestedMinimumWidth(), widthMeasureSpec);
        height = getDefaultSize(getSuggestedMinimumHeight(), heightMeasureSpec);
        setMeasuredDimension(width, height);//设置画布的大小，长和宽

        mPaintText.setTextSize(height / 26f);//设置文本字体大小
        mPaintRed.setTextSize(height / 26f);
    }

    private float x;
    private float y;

    @Override//事件监听
    public boolean onTouchEvent(MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_MOVE:
            case MotionEvent.ACTION_DOWN:
                x = event.getX();
                y = event.getY();
                if (x>width-mPaintText.measureText("m")*2){
                    index=(int)y/(height/26);
                    Log.d("onTouche", "点击到的按钮是" + array[index]);
                    if(listener!=null){
                        listener.onItemSelected(index,array[index]);
                    }
                    invalidate();//刷新
                    return  true;
                }
                break;

            case MotionEvent.ACTION_UP:
                index=-1;
                invalidate();
                return true;

        }
        return super.onTouchEvent(event);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        for (int i = 0; i < 26; i++) {
            if(index==i){
                canvas.drawText(""+array[i],width-mPaintText.measureText("m"),height/26*(i+1),mPaintRed);
            }else {
                canvas.drawText("" + array[i], width - mPaintText.measureText("m"), height / 26 * (i + 1), mPaintText);
                //mPaintText.measureText("m")文本的宽度
            }

        }
    }
}