一切正常,當我開始我的應用程序。但是當我進入下一個活動並返回SurfaceView時,它看起來像black
。當我調試時,我可以看到需要在畫布上繪製的線條,但沒有顯示出來。
這裏是我的代碼:恢復到SurfaceView顯示黑屏
public class DrawView extends SurfaceView implements Runnable
{
Thread thread = null;
SurfaceHolder holder;
Bitmap background;
Canvas canvas;
Matrix matrixUP = new Matrix();
Matrix matrixDOWN = new Matrix();
boolean ok = false;
public DrawView(Context context)
{
super(context);
holder = getHolder();
}
public void run()
{
while(ok)
{
if(!holder.getSurface().isValid())
{
continue;
}
watch_hand = Bitmap.createScaledBitmap(watch_hand, width/4, height/6, false);
watch_hand_down = Bitmap.createScaledBitmap(watch_hand_down, width/4, height/6, false);
background = BitmapFactory.decodeResource(getResources(), R.drawable.needles);
background = Bitmap.createScaledBitmap(background, width, height/2+20, false);
canvas = holder.lockCanvas();
matrixUP.setTranslate(CENTER_X - watch_hand.getWidth()/2, height/4 - watch_hand.getHeight() - 40);
matrixUP.preRotate((float) degreUP , watch_hand.getWidth()/2 , watch_hand.getHeight()-10);
matrixDOWN.setTranslate(CENTER_X - watch_hand_down.getWidth()/2, height/2 - watch_hand_down.getHeight() - 20);
matrixDOWN.preRotate((float) degreDOWN , watch_hand_down.getWidth()/2 , 10);
canvas.drawARGB(255, 255, 255, 255);
canvas.drawBitmap(background, 0, 0, null);
canvas.drawBitmap(watch_hand, matrixUP, null);
canvas.drawBitmap(watch_hand_down, matrixDOWN, null);
holder.unlockCanvasAndPost(canvas);
}
}
public void pause()
{
ok = false;
while(true)
{
try
{
thread.join();
}catch (InterruptedException e)
{
e.printStackTrace();
}
break;
}
thread = null;
}
public void resume()
{
ok = true;
thread = new Thread(this);
thread.start();
}
}
當你看到我使用的是恢復和暫停功能。他們從onCreate被調用。 爲什麼會發生這種情況,我該如何解決這個問題?
謝謝!
同樣的事情發生在我的情況下,你可以分享的解決方案。 – 2013-03-23 13:33:10