Question

如何获取第一个触摸坐标并使其保持不变。我想点击屏幕上的内容然后在第一次触摸时绘制一个永久物，然后想要在永久圆圈内移动另一个圆圈

她正在尝试的代码：

public class MainActivity extends Activity implements OnTouchListener  {
private float x;
private float y;
static float lasttouchx;
static float lasttouchy;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    MyCustomPanel view = new MyCustomPanel(this);

    ViewGroup.LayoutParams params =
            new ViewGroup.LayoutParams(LayoutParams.FILL_PARENT,
                    LayoutParams.FILL_PARENT);
    addContentView(view, params);
    view.setOnTouchListener(this);

}

private class MyCustomPanel extends View {


    public MyCustomPanel(Context context) {
        super(context);

    }
    @Override
    public void draw(Canvas canvas) {
        super.draw(canvas);

        Paint paint = new Paint();
        paint.setColor(Color.BLACK);




        paint.setStrokeWidth(5);
        paint.setTextSize(50);
        canvas.drawText(" X : " + (int) x + " Y : " + (int) y, canvas.getWidth() - 500, 200, paint);
        paint.setStyle(Paint.Style.FILL);

        if((x<=1000&& x>=18)&&(y<=1380&&y>=348)){
            paint.setColor(Color.BLUE);
            canvas.drawCircle(x, y, 100, paint);


            paint.setColor(Color.BLACK);
            paint.setStyle(Paint.Style.STROKE);
            paint.setStrokeWidth(20);
            canvas.drawCircle(lasttouchx, lasttouchy, 500, paint);


        }
        else{}




    }
}

@Override
public boolean onTouch(View v, MotionEvent event) {
    x = event.getX();
    y = event.getY();
    int action = event.getActionMasked();
   switch (action){
       case MotionEvent.ACTION_DOWN:
           lasttouchx = event.getX();
           lasttouchy = event.getY();
           return false;





    }


    v.invalidate();
    return true;
}
}

Answer 1

覆盖onTouchEvent(MotionEvent event)，然后拨打event.getX()和event.getY()以获取用户触摸位置的坐标位置。

然后将值存储到某个变量。

现在使用您想要的这些值并尝试替换为另一个。

检查堆栈答案to get touch screen information answer

如何采取初次接触坐标

1 个答案: