HoverImageView.java 文件源码

@Override
protected void onDraw(Canvas canvas) {

    Drawable maiDrawable = getDrawable();
    if (!isInEditMode() && maiDrawable instanceof BitmapDrawable) {
        Paint paint = ((BitmapDrawable) maiDrawable).getPaint();

        Rect bitmapBounds = maiDrawable.getBounds();
        rect.set(bitmapBounds);

        int saveCount = canvas.saveLayer(rect, null,
                   Canvas.MATRIX_SAVE_FLAG |
                   Canvas.CLIP_SAVE_FLAG |
                   Canvas.HAS_ALPHA_LAYER_SAVE_FLAG |
                   Canvas.FULL_COLOR_LAYER_SAVE_FLAG |
                   Canvas.CLIP_TO_LAYER_SAVE_FLAG);
        getImageMatrix().mapRect(rect);

        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        final int color = 0xffffffff;
        paint.setColor(color);
        canvas.drawPath(boundPath, paint);

        Xfermode oldMode = paint.getXfermode();
        paint.setXfermode(duffMode);
        super.onDraw(canvas);
        paint.setXfermode(oldMode);
        canvas.restoreToCount(saveCount);

        drawHover(canvas);
        drawBorder(canvas);
    } else {
        super.onDraw(canvas);
    }
}