Method onDraw

CustomView/Advance/Code/SetPolyToPoly.java:103–121

(Canvas canvas)

    }

    @Override
    protected void onDraw(Canvas canvas) {
        canvas.translate(100,100);

        // 绘制坐标系
        CanvasAidUtils.setCoordinateLen(900, 0, 1200, 0);
        CanvasAidUtils.drawCoordinateSpace(canvas);

        // 根据Matrix绘制一个变换后的图片
        canvas.drawBitmap(mBitmap, mPolyMatrix, null);

        float[] dst = new float[8];
        mPolyMatrix.mapPoints(dst,src);

        // 绘制触控点
        for (int i=0; i<testPoint*2; i+=2 ) {
            canvas.drawPoint(dst[i], dst[i+1],pointPaint);
        }
    }

    public void setTestPoint(int testPoint) {
        this.testPoint = testPoint > 4 || testPoint < 0 ? 4 : testPoint;