Question

我通过扩展View创建自定义视图，在画布上绘制一些圆圈，现在我想知道用户点击的圆圈或圆圈索引，我怎么能处理这个，我没有找到任何Circle类，所以我可以有一个Circles列表下面是我的代码----

@Override
protected void onDraw(Canvas canvas) {
    int width = canvas.getWidth();
    int height = canvas.getHeight();
    System.out.println("width : " + width + ", Height : " + height);
    paint.setColor(Color.BLACK);
    paint.setStrokeWidth(3);

    float ballDiameter = width / ((COLUMN_COUNT > ROW_COUNT) ? COLUMN_COUNT : ROW_COUNT);
    float ballRadius = ballDiameter / 2;
    Random random = new Random();
    for (int i = 0; i < ROW_COUNT; i++) {
        float cy = ballRadius + i * ballDiameter;
        for (int j = 0; j < COLUMN_COUNT; j++) {
            int nextInt = random.nextInt();
            if (nextInt % 4 == 0) {
                paint.setStyle(Paint.Style.FILL);
            } else {
                paint.setStyle(Paint.Style.STROKE);
            }
            float cx = ballRadius + j * ballDiameter;

            canvas.drawCircle(cx, cy, ballRadius, paint);
        }
    }
}

Answer 1

快速示例

float touchx;
float touchy;
float ballDiameter = width / ((COLUMN_COUNT > ROW_COUNT) ? COLUMN_COUNT : ROW_COUNT);
float ballRadius = ballDiameter / 2;
for (int i = 0; i < ROW_COUNT; i++) {
    float cy = ballRadius + i * ballDiameter;
    for (int j = 0; j < COLUMN_COUNT; j++) {
        float cx = ballRadius + j * ballDiameter;

       if(Math.sqrt(Math.pow(touchx - cx, 2) + Math.pow(touchy- cy, 2))<ballRadius){

           //CIRCLE cx,cy was touched
       }

    }
}

如何获得在画布上单击的圆圈

1 个答案: