surfaceView画图

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical"
 6      >
 7 
 8     <Button
 9         android:id="@+id/bt_clear"
10         android:layout_width="match_parent"
11         android:layout_height="wrap_content"
12         android:text="清空"
13          />
14     <com.zyhui.zyhsurfaceview.ZyhSurfaceView 
15         android:id="@+id/zyh_sfv"
16         android:layout_width="match_parent"
17         android:layout_height="match_parent"
18         />
19 
20 </LinearLayout>

 1 package com.zyhui.zyhsurfaceview;
 2 
 3 import android.os.Bundle;
 4 import android.view.View;
 5 import android.view.View.OnClickListener;
 6 import android.widget.Button;
 7 import android.app.Activity;
 8 
 9 public class MainActivity extends Activity implements OnClickListener {
10 
11     private ZyhSurfaceView zyh_sfv;
12 
13     @Override
14     protected void onCreate(Bundle savedInstanceState) {
15         super.onCreate(savedInstanceState);
16         setContentView(R.layout.activity_main);
17         zyh_sfv = (ZyhSurfaceView) findViewById(R.id.zyh_sfv);
18         Button button = (Button) findViewById(R.id.bt_clear);
19         button.setOnClickListener(this);
20     }
21 
22     @Override
23     public void onClick(View v) {
24         zyh_sfv.clear();
25     }
26 
27 }

  1 package com.zyhui.zyhsurfaceview;
  2 
  3 import java.util.ArrayList;
  4 import java.util.List;
  5 import java.util.Random;
  6 
  7 import android.content.Context;
  8 import android.graphics.Bitmap;
  9 import android.graphics.BitmapFactory;
 10 import android.graphics.Canvas;
 11 import android.graphics.Color;
 12 import android.graphics.Paint;
 13 import android.os.Handler;
 14 import android.os.HandlerThread;
 15 import android.os.Message;
 16 import android.util.AttributeSet;
 17 import android.util.Log;
 18 import android.view.MotionEvent;
 19 import android.view.SurfaceHolder;
 20 import android.view.SurfaceHolder.Callback;
 21 import android.view.SurfaceView;
 22 
 23 //====================================
 24 //1、继承SurfaceView
 25 //2、监听SurfaceView的生命周期
 26 //3、自定义线程
 27 //4、自定义线程需要的参数
 28 //5、监听线程的生命周期
 29 //6、通过SurfaceView的生命周期来执行我们的线程
 30 //7、添加触摸事件
 31 //
 32 //主要是通过线程把图片画进holder中，这样它就会显示出来；
 33 //如果直接在HandlerThread线程中更新ui控件是不行，它会报错的
 34 //====================================
 35 public class ZyhSurfaceView extends SurfaceView implements Callback {
 36 
 37     private DrawingThread drawingThread;
 38 
 39     public ZyhSurfaceView(Context context, AttributeSet attrs) {
 40         super(context, attrs);
 41         initParams();
 42     }
 43 
 44     public ZyhSurfaceView(Context context) {
 45         super(context);
 46         initParams();
 47     }
 48 
 49     private void initParams(){
 50         //监听SurfaceView的生命周期
 51         getHolder().addCallback(this);
 52     }
 53 
 54     @Override
 55     public void surfaceCreated(SurfaceHolder holder) {
 56         drawingThread = new DrawingThread(getHolder(),
 57                 BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher));
 58         drawingThread.start();
 59     }
 60 
 61     @Override
 62     public void surfaceChanged(SurfaceHolder holder, int format, int width,
 63             int height) {
 64         //Log.i("zyh", width + "-----" + height);
 65         this.drawingThread.updateSize(width, height);//更新宽和高
 66     }
 67 
 68     @Override
 69     public void surfaceDestroyed(SurfaceHolder holder) {
 70         this.drawingThread.quit();
 71         this.drawingThread = null;
 72     }
 73     
 74     @Override
 75     public boolean onTouchEvent(MotionEvent event) {
 76         if(event.getAction() == MotionEvent.ACTION_DOWN){
 77             this.drawingThread.addItem(event.getX(), event.getY());
 78         }
 79         return super.onTouchEvent(event);
 80     }
 81     
 82     //清空图片
 83     public void clear(){
 84         this.drawingThread.clear();
 85     }
 86     
 87     //自定义线程
 88     private class DrawingThread extends HandlerThread implements android.os.Handler.Callback{
 89         private static final int MSG_ADD = 101;//添加消息
 90         private static final int MSG_MOVE = 102;//消息移动
 91         private static final int MSG_CLEAR = 103;//清空
 92         
 93         //定义SurfaceView的宽和高
 94         private int drawingWidth,drawingHeight;
 95         
 96         //缓存视图
 97         private SurfaceHolder drawingHolder;
 98         //画笔
 99         private Paint paint;
100         //需要绘制的图片
101         private Bitmap iconBitmap;
102         //图片对象数组
103         private List<DrawingItem> locations;
104         //更新ui的Handler
105         private Handler receiver;
106         //线程是否在运行
107         private boolean isRunning = false;
108         
109         public DrawingThread(SurfaceHolder drawingHolder, Bitmap bitmap) {
110             super("DrawingThread");
111             this.drawingHolder = drawingHolder;
112             this.iconBitmap = bitmap;
113             this.locations = new ArrayList<DrawingItem>();
114             this.paint = new Paint(Paint.ANTI_ALIAS_FLAG);
115         }
116         
117         //监听线程的生命周期
118         @Override
119         protected void onLooperPrepared() {
120             super.onLooperPrepared();
121             this.receiver = new Handler(getLooper(),this);
122             this.isRunning = true;
123             this.receiver.sendEmptyMessage(MSG_ADD);
124         }
125         
126         @Override
127         public boolean quit() {
128             this.isRunning = false;
129             this.receiver.removeCallbacksAndMessages(null);//移除消息
130             return super.quit();
131         }
132         
133         public void updateSize(int width, int height){
134             this.drawingWidth = width;
135             this.drawingHeight = height;
136         }
137         
138         public void addItem(float x, float y){
139             Message msg = Message.obtain(receiver, MSG_ADD, (int)x, (int)y);
140             this.receiver.sendMessage(msg );
141         }
142         
143         public void clear(){
144             this.receiver.sendEmptyMessage(MSG_CLEAR);
145         }
146         
147         private class DrawingItem{
148             private int x,y;
149             private boolean isVertical,isHorizontal;
150             public DrawingItem(int x, int y, boolean isVertical,
151                     boolean isHorizontal) {
152                 this.x = x;
153                 this.y = y;
154                 this.isVertical = isVertical;
155                 this.isHorizontal = isHorizontal;
156             }
157             
158         }
159 
160         @Override
161         public boolean handleMessage(Message msg) {
162             switch(msg.what){
163                 case MSG_ADD:
164                     Random random = new Random();
165                     DrawingItem drawingItem = new DrawingItem(msg.arg1,msg.arg2,
166                             random.nextBoolean(),random.nextBoolean());
167                     locations.add(drawingItem);
168                     break;
169                 case MSG_MOVE:
170                     if(!isRunning){
171                         return true;
172                     }
173                     //获取枷锁画布
174                     Canvas lockCanvas = this.drawingHolder.lockCanvas();
175                     if(lockCanvas == null){
176                         break;
177                     }
178                     lockCanvas.drawColor(Color.BLACK);
179                     for(DrawingItem item : locations){
180                         item.x += item.isHorizontal ? 5 : -5;
181                         if(item.x > this.drawingWidth - iconBitmap.getWidth()){
182                             item.isHorizontal = false;
183                         }else{
184                             item.isHorizontal = true;
185                         }
186                         
187                         item.y += item.isVertical ? 5 : -5;
188                         if(item.y > this.drawingHeight - iconBitmap.getHeight()){
189                             item.isVertical = false;
190                         }else{
191                             item.isVertical = true;
192                         }
193                         
194                         //绘图
195                         lockCanvas.drawBitmap(iconBitmap, item.x, item.y, paint);
196                     }
197                     
198                     this.drawingHolder.unlockCanvasAndPost(lockCanvas);//释放
199                     //Log.i("zyh", Thread.currentThread().getName());
200                     break;
201                 case MSG_CLEAR:
202                     //清空图片
203                     locations.clear();
204                     break;
205                 default:
206                     break;
207             }
208             
209             if(isRunning){
210                 this.receiver.sendEmptyMessage(MSG_MOVE);//促使图片的移动
211             }
212             return false;
213         }
214     }
215 }