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したがって、UIViewであるいくつかの円を保持する可変配列があります。今、私はこのようにメソッドのセットアップを始めました。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];

    CGPoint touchLocation = [touch locationInView:self.view];

    for (Circle *circle in playerOneCircles)
    {
        if ([circle.layer.presentationLayer hitTest:touchLocation])
        {
            [circle playerTap:nil];
            break;
        } 
    }   
}

これは正常に機能します。ただし、ビューが重なると問題が発生します。他のUIviewもtouchesbeganメソッドに応答するようにします（これにより、他のメソッドがトリガーされます）。しかし、2つのオブジェクトが重なると、私のタッチが間違ったメソッドをトリガーします。

そのため、anyObjectではなく特定のオブジェクトにのみ応答する複数のUITouchを定義したいと思います。可変配列のオブジェクトのみを処理するようにUITouchを定義するにはどうすればよいですか？

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編集

コードを説明するためにコメントに答えるためのコメントを追加しました。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    // We want to find all the circles that contain the touch point.
    // A circle does not have to be "on top" (or even visible) to be touched.
    // All circles that contain the touch point will be added to the touchedCircles set.
    NSMutableSet *touchedCircles = [NSMutableSet set];

    // To support multiple touches, we have to look at every touch object.
    for (UITouch *touch in touches) {
        CGPoint touchLocation = [touch locationInView:self.view];
        // Search through our collection of circle objects.  Any circle that
        // contains this touch point gets added to our collection of touched
        // circles.  If you need to know which UITouch is "touching" each circle,
        // you will need to store that as well.
        for (Circle *circle in playerOneCircles) {
            if ([circle containsPoint:touchLocation]) {
                [touchedCircles addObject:circle];
            }
        }
    }

    // We have completed our search for all touches and all circles.  If
    // and circle was touched, then it will be in the set of touchedCircles.
    if (touchedCircles.count) {
        // When any circle has been touched, we want to call some special method
        // to process the touched circle.  Send the method the set of circles, so it
        // knows which circles were touched.
        [self methodAWithTouchedCircles:touchedCircles];
    } else {
        // None of our circles were touched, so call a different method.
        [self methodB];
    }
}

次のような円のcontainsPointを実装します...

- (BOOL)containsPoint:(CGPoint)point
{
    // Since each of our objects is a circle, to determine if a point is inside
    // the circle, we just want to know if the distance between that point and
    // the center of the circle is less than the radius of the circle.
    // If your circle is really contained inside a view, you can compute the radius
    // as one-half the width of the frame.
    // Otherwise, your circle may actually have its own radius property, in which case
    // you can just use the known radius.
    CGFloat radius = self.frame.size.width *.5;

    // This is just the Pythagorean Theorem, or instance formula.
    // distance = sqrt((x0-x1)^2 + (y0-y1)^2)
    // and we want to check that
    //     distance < radius
    // By simple algebra, that is the same as checking
    //     distance^2 < radius^2
    // which saves us from having to compute the square root.
    CGFloat diffX = self.center.x - point.x;
    CGFloat diffY = self.center.y - point.y;
    return (diffX*diffX) + (diffY*diffY) < radius*radius;
}
于 2012-04-24T17:07:42.963 に答える