Android Canvas.drawBitmap:如何绘制图像的右侧部分?

时间:2014-07-30 08:59:12

标签: android bitmap drawing android-canvas rect

我想绘制图像的右侧部分,但结果是整个位图的拉伸图像,或位图中心的拉伸部分。我在这里做错了什么?

int width;
int percentToDraw;
Random rand = new Random();
percentToDraw = rand.nextInt(100);
width = bmp.getWidth() * (100 - percentToDraw) / 100;

src = new Rect();
src.top = 0;
src.bottom = bmp.getHeight();
src.right = bmp.getWidth();
src.left = src.right - width;

dst = new Rect;
dst.top = getHeight() / 2 - bmp.getHeight() / 2;
dst.bottom = dst.top + (src.bottom - src.height);
dst.right = getWidth() / 2 + bmp.getWidth() / 2;
dst.left = dst.right - width;

canvas.drawBitmap(bmp, src, dst, paint);

我已经花了两天时间在这里搜索和搜索,宽大地找到了解决方案: - (

1 个答案:

答案 0 :(得分:0)

如果其他人偶然发现这个问题,我一直无法“正确”工作,但我找到了一个使用clipRect的工作解决方案:

        int width;
        width = (int) Math.floor(bmp.getWidth() * percentToDraw / 100.0);
        src = new Rect();
        src.top = 0;
        src.bottom = bmp.getHeight();
        src.left = 0;
        src.right = bmp.getWidth();

        dst = new Rect();
        dst.top = getHeight() / 2 - bmp.getHeight() / 2;
        dst.bottom = dst.top + (src.bottom - src.top);
        dst.left = getWidth() / 2 - bmp.getWidth() / 2;
        dst.right = dst.left + (src.right - src.left);

        canvas.clipRect(dst.right - width, 0, getWidth(), getHeight(), Region.Op.REPLACE);
        canvas.drawBitmap(bmp, src, dst, paint);
        canvas.clipRect(0, 0, getWidth(), getHeight(), Region.Op.REPLACE);