画在白色位另一个位图 [英] draw over a white bitmap another bitmap

问题描述

我想画在白色涂漆与位图乱画另一个位图，但结果始终是白色：

I'm trying to draw over a white painted bitmap another bitmap with doodles, but the result is always white:

Bitmap myBitmap = mBitmap;
Canvas canvas = new Canvas(myBitmap);
Paint paint = new Paint(Paint.FILTER_BITMAP_FLAG);
canvas.drawColor(0xffffffff);
canvas.drawBitmap(mBitmap, 0, 0, paint);
myBitmap.compress(CompressFormat.PNG, 100, output);

我怎样才能让白色为背景，和绘画在画面的前景？

How i can make white as background, and paintings as foreground in the picture?

推荐答案

回答我的问题了即将成为提问者：

answering my own question for futur askers:

Bitmap bmOverlay = Bitmap.createBitmap(mBitmap.getWidth(), mBitmap.getHeight(), mBitmap.getConfig());
Bitmap bmp2 = Bitmap.createBitmap(mBitmap.getWidth(), mBitmap.getHeight(), mBitmap.getConfig());
Canvas canvas = new Canvas(bmOverlay);
bmp2.eraseColor(0xffffffff);
canvas.drawBitmap(bmp2, new Matrix(), null);
canvas.drawBitmap(mBitmap, new Matrix(), null);

bmOverlay是我们想要的最终位图。

bmOverlay is the final bitmap we want.

这篇关于画在白色位另一个位图的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！