Android的自定义视图位图的内存泄漏 [英] Android custom view Bitmap memory leak

问题描述

我有一个自定义视图中，我需要绘制两个位图，一个是背景，再presenting地图的形象，一个是销将在画布顶部/左侧位置绘制。

I've got a custom view in which I need to draw two bitmaps, one is a background, representing the image of a map and one is a pin which will be drawn on top/left position in canvas.

的两个图像被绘制的OnDraw并保持包含该视图中的活动的活期间相同。过了一会儿，我收到了

The both images are drawn onDraw and remain the same during the live of the activity that contains the view. After a while I get a

的OutOfMemoryError：位图大小超过   VM预算

OutOfMemoryError: bitmap size exceeds VM budget

这意味着我有一个泄漏和位图没有得到垃圾收集。我以前问过这个问题，但现在情况变化不大。我做了我的设置我想使用位图一个init方法，但是这仍然不是一个好办法，后来出现的错误，但仍然存在。

This means that I have a leak and the bitmaps don't get garbage collected. I asked this question before, but now the situation changed a little. I made a init method where I set the bitmaps I want to use but this still isn't a good approach, the error appears later, but still there.

下面是code

public class MyMapView extends View {
private int xPos = 0;
private int yPos = 0;
private int space = 0;

private Bitmap resizedBitmap;
private Bitmap position;
private Bitmap mapBitmap;

public void setMapBitmap(Bitmap value) {
    this.mapBitmap =  value;
}

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

public MyMapView(Context context, AttributeSet attrs) {
 super(context, attrs);
}

public MyMapView(Context context, AttributeSet attrs, int defStyle) {
 super(context, attrs, defStyle);
}

public void init(final Context context) {
 Paint paint = new Paint();
    paint.setFilterBitmap(true);

    int width = getMeasuredWidth();
    int height = getMeasuredHeight();

    resizedBitmap = Bitmap.createScaledBitmap(mapBitmap, height, height, true);
    position = BitmapFactory.decodeResource(getContext().getResources(), R.drawable.position);
    space = (width - resizedBitmap.getWidth()) / 2;
}

public void destroy()
{
 resizedBitmap.recycle();
 resizedBitmap=null;
 position.recycle();
 position=null;
 mapBitmap.recycle();
 mapBitmap=null;
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec), MeasureSpec.getSize(heightMeasureSpec));
}

@Override
protected void onDraw(Canvas canvas) {

     if (mapBitmap != null) {
         canvas.drawBitmap(resizedBitmap, space, 0, null);
     }

     if (xPos != 0 && yPos != 0) {
         canvas.translate(xPos + space - position.getWidth() / 2, yPos - position.getHeight() / 2);
         canvas.drawBitmap(position, new Matrix(), new Paint());

     }
}

 public void updatePosition(int xpos, int ypos)
 {
   xPos = xpos;
      yPos = ypos;
      invalidate();
 }
}

我调用包含视图的活动上的onCreate的setMapBitmap（）和init（）。在那里，我知道什么是位图将被用作地图。的onPause活动中我调用视图的destroy（）方法。我仍然得到错误。 我读过这这个但我不知道该怎么对我来说，适应它

I call the setMapBitmap() and init() on onCreate of the activity that contains the view. In there I know what bitmap will be used as map. onPause of the activity I call the destroy() of the view. I still get errors. I've read this this but I don't know how to adapt it on my case

我愿意接受任何其他解决方案。请注意，我需要调整地图的位图（基于包含它的迈活动布局的高度），仍然能够吸取正确的位置的位置。

I AM OPEN TO ANY OTHER SOLUTION. Please note that I need to resize the map bitmap (based on the height of the layout that contains it in mai activity) and still be able to draw the position on correct place.

推荐答案

您明明有内存泄漏。了解如何避免内存泄漏以及如何find内存泄漏的。

You obviously have a memory leak. Read how to avoid memory leaks and how to find memory leaks.

下面是你的code重构使用WeakReference的：

Here is a your code refactored to use WeakReference:

public class MyMapView extends View {
    private int xPos = 0;
    private int yPos = 0;
    private int space = 0;

    private WeakReference<Bitmap> resizedBitmap;
    private WeakReference<Bitmap> position;
    private WeakReference<Bitmap> mapBitmap;

    public void setMapBitmap(Bitmap value) {
        this.mapBitmap = new WeakReference<Bitmap>(value);
    }

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

    public MyMapView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public MyMapView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public void init(Bitmap mapBitmap) {
        Paint paint = new Paint();
        paint.setFilterBitmap(true);

        int width = getMeasuredWidth();
        int height = getMeasuredHeight();

        resizedBitmap = new WeakReference<Bitmap>(Bitmap.createScaledBitmap(
            mapBitmap, width, height, true));
        position = new WeakReference(BitmapFactory.decodeResource(
            getContext().getResources(), R.drawable.position));
        space = (width - resizedBitmap.get().getWidth()) / 2;
    }

//    public void destroy() {
//        resizedBitmap.recycle();
//        resizedBitmap = null;
//        position.recycle();
//        position = null;
//        mapBitmap.recycle();
//        mapBitmap = null;
//    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec),
            MeasureSpec.getSize(heightMeasureSpec));
    }

    @Override
    protected void onDraw(Canvas canvas) {

        if (mapBitmap != null) {
            canvas.drawBitmap(resizedBitmap.get(), space, 0, null);
        }

        if (xPos != 0 && yPos != 0) {
            canvas.translate(xPos + space - position.get().getWidth() / 2, 
                yPos - position.get().getHeight() / 2);
            canvas.drawBitmap(position.get(), new Matrix(), null);

        }
    }

    public void updatePosition(int xpos, int ypos) {
        xPos = xpos;
        yPos = ypos;
        invalidate();
    }
}

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