如何在特定的位置繪製點並在這些點之間用手指拖動畫線？

Question

我試圖在屏幕上繪製兩個點&當我觸摸point1並將其拖動到point2時，需要從point1到point2繪製一條線。

如下面圖像所示

Answer 1

關注這個代碼觸摸事件用於拖動

@Override 
public boolean onTouchEvent (MotionEvent event) { 

    if (event.getAction() == MotionEvent.ACTION_DOWN) { 

    start_x = event.getX(); 
    start_y = event.getY();  

    } else if (event.getAction() == MotionEvent.ACTION_MOVE) { 

    //create the line from start_x and start_y to the current location 
    //don't forget to invalidate the View otherwise your line won't get redrawn 

    } else if (event.getAction() == MotionEvent.ACTION_UP) { 

    //might not need anything here 

    } 

而對於拉線此鏈接 How to draw a line in android