Question

我有一个自定义ViewGroup，我将其覆盖dispatchDraw并绘制一些额外的Path，如下所示：

@Override
public void dispatchDraw(Canvas canvas) {
    super.dispatchDraw(canvas);
    canvas.setMatrix(matrix);
    mRegions.clear();
    canvas.drawPicture(mPicture);
    if (drawShader) {
        canvas.drawBitmap(mShader, 0, 0, mBitmapPaint);
    }
    for (int i = 0; i < mPaths.size(); i++) {
        if (mIndex != -1 && mIndex == i) {
            canvas.save();
            canvas.drawRect(mRect, mPaint);
            drawPaths(canvas, mPaths.get(i));
            canvas.clipPath(mPaths.get(i), Region.Op.INTERSECT);
            canvas.drawColor(mOverlayColor);
            Rect f = mRegions.get(i).getBounds();
            mPaint.setColor(Color.RED);
            mPaint.setStyle(Paint.Style.STROKE);
            canvas.drawCircle(f.centerX() - mRadius, f.centerY() - mRadius, mRadius, mPaint);
            canvas.restore();
        } else {
            drawPaths(canvas, mPaths.get(i));
        }
    }
}

现在我想要的是添加一个孩子，这个孩子会放在dispatchDraw上绘制的这些东西之上。现在我这样做：

    mBalloon = LayoutInflater.from(getContext()).inflate(R.layout.map_balloon, null);
    LayoutParams params = new LayoutParams(500, 150);
    mBalloon.setLayoutParams(params);
    addView(mBalloon);
    bringChildToFront(getChildAt(0));

在我的init()构造函数中调用的ViewGroup方法中，结果是dispatchDraw中的绘图位于mBalloon之上。

任何想法如何将View - mBalloon置于dispatchDraw之上？{/ p>

提前致谢！

Answer 1

为了吸引额外Path以上的孩子，您应在绘制super.dispatchDraw(canvas)后致电Path。

@Override
public void dispatchDraw(Canvas canvas) {
    canvas.setMatrix(matrix);
    mRegions.clear();
    canvas.drawPicture(mPicture);
    if (drawShader) {
        canvas.drawBitmap(mShader, 0, 0, mBitmapPaint);
    }
    for (int i = 0; i < mPaths.size(); i++) {
        if (mIndex != -1 && mIndex == i) {
            canvas.save();
            canvas.drawRect(mRect, mPaint);
            drawPaths(canvas, mPaths.get(i));
            canvas.clipPath(mPaths.get(i), Region.Op.INTERSECT);
            canvas.drawColor(mOverlayColor);
            Rect f = mRegions.get(i).getBounds();
            mPaint.setColor(Color.RED);
            mPaint.setStyle(Paint.Style.STROKE);
            canvas.drawCircle(f.centerX() - mRadius, f.centerY() - mRadius, mRadius, mPaint);
            canvas.restore();
        } else {
            drawPaths(canvas, mPaths.get(i));
        }
    }
    super.dispatchDraw(canvas);
}

Answer 2

我理解你想要达到的目标的一般概念，我会尝试建议一种不同的方法。

来自文档：A ViewGroup is a special view that can contain other views (called children.) The view group is the base class for layouts and views containers.

因此ViewGroup根本不应该在屏幕上绘制内容。有可能做到吗？是的，但它只是使你的OO结构不太适当。

所以我的建议是使用你喜欢的任何ViewGroup FrameLayout，RelativeLayout等。并将路径绘制代码迁移到一个自定义视图，它将在屏幕中绘制所有这些路径，在标准ViewGroup中你只需要定位自定义查看相应。可能是这样的：

<RelativeLayout>

    <TextView/> // just an example
    <ImageView/> // just an example

    <CustomPathView/> // your custom view

    <FrameLayout/>  // in this frame you can put views to be on top
</RelativeLayout>

Android ViewGroup在所有图纸上添加子项

2 个答案: