Android: Mirroring a View

Question

I have a view I need to flip vertically, or mirror. There\'s plenty of information out there about mirroring a single bitmap by scaling it by -1 and translating for the offset,

Answer 1

Transfer View into Bitmap, then flip it using method below:

private static Bitmap getBitmapFromView(View view,int width,int height) {
    int widthSpec = View.MeasureSpec.makeMeasureSpec(width, View.MeasureSpec.EXACTLY);
    int heightSpec = View.MeasureSpec.makeMeasureSpec(height, View.MeasureSpec.EXACTLY);
    view.measure(widthSpec, heightSpec);
    view.layout(0, 0, width, height);
    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    view.draw(canvas);

    return bitmap;
}


private static Bitmap flipBitmap(Bitmap src)
{
    Matrix matrix = new Matrix();
    matrix.preScale(-1, 1);
    Bitmap dst = Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, false);
    dst.setDensity(DisplayMetrics.DENSITY_DEFAULT);
    return dst;
}

Answer 2

You could simply create a Canvas out of a Bitmap and then invoke your root view's View.draw(Canvas) method. This will give you a snapshot of the view hierarchy in a Bitmap. You then apply the aforementioned transformations to mirror the image.