Question

我正在尝试从菜单按钮（类似于Path上的+按钮）弹出按钮，并使用UIDynamicAnimator为按钮捕捉和切换设置动画。它的工作原理和代码非常简单。

    _animator = [[UIDynamicAnimator alloc] initWithReferenceView:sender.superview];

    UIDynamicItemBehavior *resistance = [[UIDynamicItemBehavior alloc] initWithItems:@[_cartBtn, _chatBtn, _eventBtn]];
    resistance.resistance = 5.0f;
    [_animator addBehavior:resistance];

    CGFloat radius = 75;
    CGPoint target = sender.center;
    target.x += radius * cos(GLKMathDegreesToRadians(265));
    target.y += radius * sin(GLKMathDegreesToRadians(265));
    UISnapBehavior *snapBehavior = [[UISnapBehavior alloc] initWithItem:_cartBtn snapToPoint:target];
    [_animator addBehavior:snapBehavior];

    target = sender.center;
    target.x += radius * cos(GLKMathDegreesToRadians(225));
    target.y += radius * sin(GLKMathDegreesToRadians(225));
    UISnapBehavior *snapBehavior2 = [[UISnapBehavior alloc] initWithItem:_chatBtn snapToPoint:target];
    [_animator addBehavior:snapBehavior2];

    target = sender.center;
    target.x += radius * cos(GLKMathDegreesToRadians(185));
    target.y += radius * sin(GLKMathDegreesToRadians(185));
    UISnapBehavior *snapBehavior3 = [[UISnapBehavior alloc] initWithItem:_eventBtn snapToPoint:target];
    [_animator addBehavior:snapBehavior3];

这样，所有三个按钮一起弹出。我问的是，是否可以使用UIDynamicAnimator使按钮动画一个接一个地，或者其他什么，但这很简单？

Answer 1

显然我只需要在[[NSRunLoop currentRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.1]];

之间添加addBehavior:之类的微小延迟

UIDynamicAnimator连续动画

1 个答案: