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Android:SurfaceView上的背景?

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我有一个表面视图,每当我触摸屏幕时,我触摸的位置会出现一个图像 . 这很棒,但我无法弄清楚如何在SurfaceView上放置背景 . 我已经尝试使用OnDraw立即绘制背景(无需触摸它),并且只在某些时候有效 . 它强制关闭大部分时间 .

有人想看看我的代码,看看是否有可能在Surface视图上获得背景图像?提前致谢 .

类MyView扩展SurfaceView实现SurfaceHolder.Callback {private Thready _thread; private ArrayList _graphicsz = new ArrayList(); private GraphicObject _currentGraphic = null;

public MyView(Context context) {
    super(context);
    getHolder().addCallback(this);
    _thread = new Thready(getHolder(), this);
    setFocusable(true);
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    synchronized (_thread.getSurfaceHolder()) {
        GraphicObject graphic = null;
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            graphic = new GraphicObject(BitmapFactory.decodeResource(getResources(), R.drawable.cat1small));
            graphic.getCoordinates().setX((int) event.getX() - graphic.getGraphic().getWidth() / 2);
            graphic.getCoordinates().setY((int) event.getY() - graphic.getGraphic().getHeight() / 2);
            _currentGraphic = graphic;
        } else if (event.getAction() == MotionEvent.ACTION_MOVE) {
            _currentGraphic.getCoordinates().setX((int) event.getX() - _currentGraphic.getGraphic().getWidth() / 2);
            _currentGraphic.getCoordinates().setY((int) event.getY() - _currentGraphic.getGraphic().getHeight() / 2);
        } else if (event.getAction() == MotionEvent.ACTION_UP) {
            _graphicsz.add(_currentGraphic);
            _currentGraphic = null;
        }

        return true;
    }
}

@Override
public void onDraw(Canvas canvas) {


    canvas.drawColor(Color.BLACK);
    Bitmap bitmap1;
    GraphicObject.Coordinates coords1;
    for (GraphicObject graphic : _graphicsz) {
        bitmap1 = graphic.getGraphic();
        coords1 = graphic.getCoordinates();
        canvas.drawBitmap(bitmap1, coords1.getX(), coords1.getY(), null);
    }
    // draw current graphic at last...
    if (_currentGraphic != null) {
        bitmap1 = _currentGraphic.getGraphic();
        coords1 = _currentGraphic.getCoordinates();
        canvas.drawBitmap(bitmap1, coords1.getX(), coords1.getY(), null);
    }
}

public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    // TODO Auto-generated method stub
}

public void surfaceCreated(SurfaceHolder holder) {
    _thread.setRunning(true);
    _thread.start();
}




public void surfaceDestroyed(SurfaceHolder holder) {
    // simply copied from sample application LunarLander:
    // we have to tell thread to shut down & wait for it to finish, or else
    // it might touch the Surface after we return and explode
    boolean retry = true;
    _thread.setRunning(false);
    while (retry) {
        try {
            _thread.join();
            retry = false;
        } catch (InterruptedException e) {
            // we will try it again and again...
        }
    }
}

} class Thready extends Thread {private SurfaceHolder _surfaceHolder;私人MyView _panel; private boolean _run = false;

public Thready(SurfaceHolder surfaceHolder, MyView panel) {
    _surfaceHolder = surfaceHolder;
    _panel = panel;
}

public void setRunning(boolean run) {
    _run = run;
}

public SurfaceHolder getSurfaceHolder() {
    return _surfaceHolder;
}

@Override
public void run() {
    Canvas c;
    while (_run) {
        c = null;
        try {
            c = _surfaceHolder.lockCanvas(null);
            synchronized (_surfaceHolder) {
                _panel.onDraw(c);
            }
        } finally {
            // do this in a finally so that if an exception is thrown
            // during the above, we don't leave the Surface in an
            // inconsistent state
            if (c != null) {
                _surfaceHolder.unlockCanvasAndPost(c);
            }
        }
    }
}

} class GraphicObject {/ ** *包含图形的坐标 . * / public class Coordinates {private int _x = 100; private int _y = 0;

public int getX() {
        return _x + _bitmap.getWidth() / 2;
    }

    public void setX(int value) {
        _x = value - _bitmap.getWidth() / 2;
    }

    public int getY() {
        return _y + _bitmap.getHeight() / 2;
    }

    public void setY(int value) {
        _y = value - _bitmap.getHeight() / 2;
    }

    public String toString() {
        return "Coordinates: (" + _x + "/" + _y + ")";
    }
}

private Bitmap _bitmap;
private Coordinates _coordinates;

public GraphicObject(Bitmap bitmap) {
    _bitmap = bitmap;
    _coordinates = new Coordinates();
}

public Bitmap getGraphic() {
    return _bitmap;
}

public Coordinates getCoordinates() {
    return _coordinates;
}

}

1 回答

  • 0

    那么,首先让我感到震惊的是什么(以及可能造成很多问题的原因)是这样的:

    你经常创建新的位图方式

    每当你接触到触摸事件时,你就会加载你的位图......你每秒钟可以获得80到100次触摸事件!

    首先,定义全局位图(私有位图bmp1;等),将它们加载到其他地方,然后在触摸事件中使用它们 .

    另外,从onDraw中删除bmp加载/创建并将其移动到其他位置 .

    完成后,看看会发生什么;你可能有更多的问题(REALY快速扫描你的代码似乎很好),但不是每秒80次创建和加载位图肯定会有帮助:)

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