android.graphics.drawable.ShapeDrawable#draw()源码实例Demo

public void onDraw(Canvas canvas)
{
    super.onDraw(canvas);

    //将图片裁剪为椭圆形
    /* 构建ShapeDrawable对象并定义形状为椭圆 */
    mShapeDrawableQQ = new ShapeDrawable(new OvalShape());

    /* 设置要绘制的椭圆形的东西为ShapeDrawable图片 */
    mShapeDrawableQQ.getPaint().setShader(mBitmapShader);

    /* 设置显示区域 */
    mShapeDrawableQQ.setBounds(0,0, BitQQwidth, BitQQheight);

    /* 绘制ShapeDrawableQQ */
    mShapeDrawableQQ.draw(canvas);

    //绘制渐变的矩形
    mPaint.setShader(mLinearGradient);
    canvas.drawRect(BitQQwidth, 0, 320, 156, mPaint);

    //显示混合渲染效果
    mPaint.setShader(mComposeShader);
    canvas.drawRect(0, 300, BitQQwidth, 300+BitQQheight, mPaint);

    //绘制环形渐变
    mPaint.setShader(mRadialGradient);
    canvas.drawCircle(50, 200, 50, mPaint);

    //绘制梯度渐变
    mPaint.setShader(mSweepGradient);
    canvas.drawRect(150, 160, 300, 300, mPaint);

}
 

private void setSpaceCorner(Canvas canvas, int trueHeight) {
    int leftTop;
    int rightTop;
    int rightBottom;
    int leftBottom;
    if (mCornerRadius_leftTop == -1) {
        leftTop = (int) mCornerRadius;
    } else {
        leftTop = (int) mCornerRadius_leftTop;
    }

    if (leftTop > trueHeight / 2) {
        leftTop = trueHeight / 2;
    }

    if (mCornerRadius_rightTop == -1) {
        rightTop = (int) mCornerRadius;
    } else {
        rightTop = (int) mCornerRadius_rightTop;
    }

    if (rightTop > trueHeight / 2) {
        rightTop = trueHeight / 2;
    }

    if (mCornerRadius_rightBottom == -1) {
        rightBottom = (int) mCornerRadius;
    } else {
        rightBottom = (int) mCornerRadius_rightBottom;
    }

    if (rightBottom > trueHeight / 2) {
        rightBottom = trueHeight / 2;
    }


    if (mCornerRadius_leftBottom == -1) {
        leftBottom = (int) mCornerRadius;
    } else {
        leftBottom = (int) mCornerRadius_leftBottom;
    }

    if (leftBottom > trueHeight / 2) {
        leftBottom = trueHeight / 2;
    }

    float[] outerR = new float[]{leftTop, leftTop, rightTop, rightTop, rightBottom, rightBottom, leftBottom, leftBottom};//左上，右上，右下，左下
    ShapeDrawable mDrawables = new ShapeDrawable(new RoundRectShape(outerR, null, null));
    mDrawables.getPaint().setColor(paint.getColor());
    mDrawables.setBounds(leftPading, topPading, getWidth() - rightPading, getHeight() - bottomPading);
    mDrawables.draw(canvas);
}
 

/**
 * Draw points in chart.
 *
 * @param canvas Canvas to draw the chart.
 */
private void drawPoints(Canvas canvas) {
    for (ShapeDrawable pointsShape : pointsShapes) {
        pointsShape.draw(canvas);
    }
}