1992
surfaceview 如何实现截图
|
|
|
对于surfaceview使用buildDrawingCache是不行的 可以通过SurfaceHolder来变通地截屏 你在线程里面是否使用下面的方式不停地绘图 canvas = mHolder.lockCanvas(); if (canvas != null) { 把surfaceview的内容绘制到canvas 上 surfaceview.doDraw(canvas); mHolder.unlockCanvasAndPost(canvas); } 有了这一点应该就比较好理解了，上面的canvas其实是绘制到屏幕上的，可以使用一个bitmap创建一个canvas，然后把surfaceview绘制到这个canvas上就行了 Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888); Canvas bitCanvas = new Canvas(bitmap); surfaceview.doDraw(bitCanvas); |
David_Zhang 发表于 2012-2-21 20:42 你好 首先谢谢你的回答 ，我按照你的方法做了。没有使用canvas = mHolder.lockCanvas(); 而是自己创建的canvas，但是这个时候，屏幕上就是一片黑的啊 什么也看不见 而且 我在保存自己生成Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Bitmap.Config.ARGB_8888); 的时候，还是看不见图像。。 package com.pica.whiteboard.view; import java.util.ArrayList; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.view.MotionEvent; import android.view.SurfaceHolder; import android.view.SurfaceView; import com.pica.whiteboard.activity.R; import com.pica.whiteboard.util.PaintHolder; public class PaletteView extends SurfaceView implements Runnable, SurfaceHolder.Callback{ private Paint mPaint = null; //定义集合，存储画笔动作 private ArrayList<Action> actionList; private Action curAction = null; boolean mLoop = true; SurfaceHolder mSurfaceHolder = null; Bitmap bgBitmap = null; //背景 Bitmap tempBitmap = null; //临时画板 public PaletteView(Context context) { super(context); this.mPaint = new Paint(); this.actionList = new ArrayList<Action>(); mSurfaceHolder = this.getHolder(); mSurfaceHolder.addCallback(this); this.setFocusable(true); mLoop = true; // bgBitmap = BitmapFactory.decodeStream(getResources().openRawResource(R.drawable.defaultbgimg)); bgBitmap = Bitmap.createBitmap(320, 320, Config.ARGB_8888); tempBitmap = Bitmap.createBitmap(320, 320, Config.ARGB_8888); new Thread(this).start(); } private void Draw() { // Canvas canvas = mSurfaceHolder.lockCanvas(); Canvas canvas = new Canvas(bgBitmap); if (mSurfaceHolder == null || canvas == null) { return; } // canvas.drawColor(Color.parseColor("#00000000")); // 设置画笔没有锯齿，空心 mPaint.setAntiAlias(true); mPaint.setStyle(Paint.Style.STROKE); // 画板绘图区背景图片 canvas.drawBitmap(bgBitmap, 0, 0, null); canvas.drawColor(Color.parseColor("#FFFFFFFF")); // tempBitmap = Bitmap.createBitmap(bgBitmap.getWidth(), bgBitmap.getHeight(), Config.ARGB_4444); tempBitmap = Bitmap.createBitmap(320, 320, Config.ARGB_8888); Canvas canvasTemp = new Canvas(tempBitmap); canvasTemp.drawColor(Color.TRANSPARENT); for(int i=0;i <= PaintHolder.curIndex; i++){ actionList.get(i).draw(canvasTemp); } // 画当前画笔痕迹 if (curAction != null) { curAction.draw(canvasTemp); } // 在主画板上绘制临时画布上的图像 canvas.drawBitmap(tempBitmap, 0, 0, null); // mSurfaceHolder.unlockCanvasAndPost(canvas); } //触屏事件 @Override public boolean onTouchEvent(MotionEvent event) { int mAction = event.getAction(); if(mAction == MotionEvent.ACTION_CANCEL) { return false; } float touchX = event.getX(); float touchY = event.getY(); //点击时 if(mAction == MotionEvent.ACTION_DOWN) { setCurAction(touchX, touchY); clearSpareAction(); } // 拖动时 if (mAction == MotionEvent.ACTION_MOVE) { if (curAction != null) { curAction.move(touchX, touchY); } } // 抬起时 if (mAction == MotionEvent.ACTION_UP) { if (curAction != null) { curAction.move(touchX, touchY); actionList.add(curAction); PaintHolder.curIndex++; curAction = null; } } return super.onTouchEvent(event); } public void setCurAction(float x, float y) { switch(PaintHolder.curTool) { case 0: curAction = new MyPath(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 1: curAction = new MyLine(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 2: curAction = new MyCircle(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 3: curAction = new MyRect(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 4: curAction = new MyFillRect(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 5: curAction = new MyFillCircle(x, y, PaintHolder.curSize, PaintHolder.curColor); break; case 6: curAction = new MyEraser(x, y, PaintHolder.curSize, PaintHolder.curColor); break; } } public void surfaceCreated(SurfaceHolder holder) { // TODO Auto-generated method stub } public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { // TODO Auto-generated method stub } public void surfaceDestroyed(SurfaceHolder holder) { // TODO Auto-generated method stub } public void run() { while (mLoop) { try { Thread.sleep(50); } catch (InterruptedException e) { e.printStackTrace(); } synchronized (mSurfaceHolder) { Draw(); } } } // 后退前进完成后，缓存的动作 private void clearSpareAction() { for (int i = actionList.size() - 1; i > PaintHolder.curIndex; i--) { actionList.remove(i); } } public int getListLength() { return this.actionList.size(); } public Bitmap getBitMap(){ return this.bgBitmap; } } |
David_Zhang 发表于 2012-2-21 20:42 多谢 LZ 我终于懂了...昨天没有理解透..效果做出来了...十分感谢 但是还是有一点 小小的毛病 就是每次截图的时候虽然可以截图成功 但是导出工程的时候是没有办法预览的 必须关闭eclipse,然后才可以看 我不清楚这是怎么回事. 另外附上一个外国朋友些的源码.跟LZ的思想是一样的..再次非常感谢! |
15.53 KB, 下载次数: 1173
详情 回复 David_Zhang 发表于 2012-2-23 16:12:42
关于我们|手机版|Archiver|DEVDIV.COM ( 京ICP备07040843号 )
GMT+8, 2012-5-19 16:44
Powered by DEVDIV.COM!
© 2010-2012 DEVDIV.COM Coummunity.
，应该不还eclipse的问题