如何在Android中添加圆角到画布画？

Question

我在@Override方法中创建一个矩形ReplacementSpan.如何添加RoundCorner和padding它？

码:

@Override
public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint) {
    RectF rect = new RectF(x, top, x + measureText(paint, text, start, end), bottom);
    paint.setColor(mBackgroundColor);
    canvas.drawRect(rect, paint);
    paint.setColor(mForegroundColor);
    canvas.drawText(text, start, end, x, y, paint);
}

编辑-1

我正在使用MeasureText:

private float measureText(Paint paint, CharSequence text, int start, int end) { return paint.measureText(text, start, end); }

编辑-2

经过一些建议,我做了这些改变,我可以看到 Rounded角落Rectangle

@Override
public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint) {
    RectF rect = new RectF(x, top, x + measureText(paint, text, start, end), bottom);
    paint.setColor(mBackgroundColor);
    canvas.drawRoundRect(rect, 15,15,paint);
    paint.setColor(mForegroundColor);
    canvas.drawText(text, start, end, x, y, paint);

}

这是截图:

我draw从以下代码调用方法:

int currentIndex = 0;
for (int i = 0; i < words.length - 1; i++) {
            s.setSpan(new CustomDrawble(Color.GRAY, Color.WHITE), currentIndex, currentIndex + words[i].length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
            currentIndex += words[i].length() + 1;
        }

Answer 1

Canvas的方法是drawRoundRect.您将必须提供RectF要绘制的Paint,drawRect以及两个附加参数,rx并且ry表示圆角的x和y半径.例如

canvas.drawRoundRect(rect, 5, 5, paint);

将绘制一个圆角为5像素的矩形

EDIT2:

免责声明:使用dip而不是像素

@Override
public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom, Paint paint) {
   RectF rect = new RectF(x, top, x + measureText(paint, text, start, end) + 10, bottom);
   paint.setColor(mBackgroundColor);
   canvas.drawRoundRect(rect, 15,15,paint);
   paint.setColor(mForegroundColor);
   canvas.drawText(text, start, end, x + 5, y, paint); 
 }