objective-c - 目標 C: 開始点と終了点

Question

指アプリで絵を描いています。

始点と終点を設定したい。

私のプロジェクトはこんな感じで、描く方向を教えてくれる背景があります。ユーザーが終点に到達すると、背景が変化します。

私はこれを試しました...タッチが始まりました...

    drawPoint = [touch locationInView:self.view];
    CGRect writingStartPoint = CGRectMake(90, 800, 30, 30);
    CGRect writingEndPoint = CGRectMake(390, 800, 30, 30);

    if (CGRectContainsPoint(writingStartPoint, drawPoint))
    {
        //something
    }

   if (CGRectContainsPoint(writingEndPoint, drawPoint))
        {
            //change background
        }

動いていない。

別の方法はありますか？

Answer 1

タッチ移動または終了メソッドで終了長方形にタッチしているかどうかを確認する必要があります

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [touches anyObject];
    CGPoint drawPoint = [touch locationInView:self.view];
    CGRect writingStartPoint = CGRectMake(90, 800, 30, 30);
    if (CGRectContainsPoint(writingStartPoint, drawPoint))
    {
        //something
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [touches anyObject];
    CGPoint drawPoint = [touch locationInView:self.view];
    CGRect writingEndPoint = CGRectMake(390, 800, 30, 30);
    if (CGRectContainsPoint(writingEndPoint, drawPoint))
    {
        //change background if you want user see change without lift finger up
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [touches anyObject];
    CGPoint drawPoint = [touch locationInView:self.view];
    CGRect writingEndPoint = CGRectMake(390, 800, 30, 30);
    if (CGRectContainsPoint(writingEndPoint, drawPoint))
    {
        //change background when user lift finger up
    }
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
    // handle cancel event
}