Question

我的应用程序İ想让球在特定区域（矩形）内移动。直到现在，球在矩形下方的背景区域中在屏幕周围移动。我试过几次改变坐标，但它没有用。任何人都可以帮助我让球在矩形内移动吗？

class DrawView extends View {

    int x,y,x1,y1;
    int a=431,b=641, a1=54,b1=54;
    int sayac=0;
    Canvas can;
    Paint paint = new Paint();
    Rect r = new Rect(60, 60, 400, 610);
    Paint por= new Paint();
  //  Font bold;
    public DrawView(Context context) {
        super(context);
        paint.setColor(Color.RED);


    }

private void update() {

       if(a>605){x=-(int)(Math.random()*7+5);   }
       if(a<55){x=(int)(Math.random()*7+5);  }
       if(b>395){y=-(int)(Math.random()*7+5);  }
       if(b<55){y=(int)(Math.random()*7+5);  }

       if(a1>605){x1=-(int)(Math.random()*7+5);   }
       if(a1<55){x1=(int)(Math.random()*7+5);  }
       if(b1>395){y1=-(int)(Math.random()*7+5);  }
       if(b1<55){y1=(int)(Math.random()*7+5);  }


       a+=x;
       b+=y;

       a1+=x1;
       b1+=y1;

       }



  @Override
  protected void onDraw(Canvas canvas) {


               paint.setTextSize(20);
               paint.setColor(Color.YELLOW);
               canvas.drawCircle(a, b, 50, paint);
               paint.setColor(Color.BLUE);
               canvas.drawText("Pamukcu", a-41, b+7, paint);


               /* paint.setColor(Color.RED);

               canvas.drawLine(40, 40, 600, 40, paint);
               paint.setStrokeWidth(10f);
               canvas.drawLine(40, 600, 600, 600, paint);
               canvas.drawLine(40, 40, 40, 600, paint);
               canvas.drawLine(600, 40, 40, 600, paint);
       */
               paint.setStyle(Paint.Style.FILL);
               paint.setColor(Color.MAGENTA); 
               canvas.drawRect(r, paint); 

              update();   

               try{
                      Thread.sleep(1);
               }catch(InterruptedException e){ }

               invalidate();

private void update() {

       if(a>605){x=-(int)(Math.random()*7+5);   }
       if(a<55){x=(int)(Math.random()*7+5);  }
       if(b>395){y=-(int)(Math.random()*7+5);  }
       if(b<55){y=(int)(Math.random()*7+5);  }

       if(a1>605){x1=-(int)(Math.random()*7+5);   }
       if(a1<55){x1=(int)(Math.random()*7+5);  }
       if(b1>395){y1=-(int)(Math.random()*7+5);  }
       if(b1<55){y1=(int)(Math.random()*7+5);  }


       a+=x;
       b+=y;

       a1+=x1;
       b1+=y1;

       }
   @Override
  protected void onDraw(Canvas canvas) {


               paint.setTextSize(20);
               paint.setColor(Color.YELLOW);
               canvas.drawCircle(a, b, 50, paint);
               paint.setColor(Color.BLUE);
               canvas.drawText("Ball", a-41, b+7, paint);

Answer 1

如果你想要球只能在矩形内移动，你可以这样做：

int rectangleX = 100;
int rectangleY = 100;
int rectangleWidht = 200;
int rectangleHeight = 300;

private void KeepBallInsideRectangle() {
  if (ballX < rectanlgeX) ballX = rectangleX;
  if (ballX > rectangleX+rectangleWidth) ballX = rectangleX+rectangleWidth;
  if (ballY < rectanlgeY) ballY = rectangleY;
  if (ballY > rectangleY+rectanglHeight) ballY = rectangleY+rectangleHeight;
}

您只需检查球的位置是否在矩形之外，然后将其位置设置为矩形的边框。

如何使一个balll移动到android中指定区域的矩形

1 个答案: