UIView setHidden：NO like dropdown

Question

我有一個初始隱藏的UIView。我需要setHidden：NO（可視）具有下拉作用...

有我的簡單的代碼，而不影響

-(IBAction)btnAbrirDestaquesClick:(id)sender { 
[self.viewDestaques setHidden:NO]; 
} 

Answer 1

在iOS的7 UIDynamicAnimator一個更簡單的方法是春季動畫（新的強大的UIView塊動畫），它可以給你很好的彈跳效果與阻尼和速度：

[UIView animateWithDuration:duration 
    delay:delay 
    usingSpringWithDamping:damping 
    initialSpringVelocity:velocity 
    options:options animations:^{ 
    //Animations 
    [self.viewDestaques setHidden:NO]; 

    } 
    completion:^(BOOL finished) { 
    //Completion Block 
}]; 

Answer 2

如果你只是想製作動畫嘗試是這樣的：

[UIView animateWithDuration:.5 delay:0.0 options:UIViewAnimationOptionCurveEaseIn animations:^{ 
    self.viewDestaques.frame = CGRectMake(0, 0, 320,30); 
} completion:^(BOOL finished) { 

    [UIView animateWithDuration:.5 delay:2.0 options:UIViewAnimationOptionCurveEaseIn animations:^{ 
     self.viewDestaques.frame = CGRectMake(0, -30, 320,30); 

    } completion:^(BOOL finished) { 

    }]; 

}]; 

Answer 3

它的工作對我來說：

-(IBAction)btnAbrirDestaquesClick:(id)sender { 
[self.viewDestaques setTranslatesAutoresizingMaskIntoConstraints:YES]; //respeita o frame que eu setar, independentemente das constraints 

[self.viewDestaques setFrame:CGRectMake(self.viewDestaques.frame.origin.x, self.viewDestaques.frame.origin.y, self.viewDestaques.frame.size.width, 0)]; 

[self.viewDestaques setHidden:NO]; 

while (self.viewDestaques.frame.size.height < self.frameViewDestaquesOriginal.size.height) { 


    [UIView animateWithDuration:2.0 animations:^{ 
     [self.viewDestaques setFrame:CGRectMake(self.viewDestaques.frame.origin.x, self.viewDestaques.frame.origin.y, self.viewDestaques.frame.size.width, self.view.frame.size.height + 10)]; 
    }completion: ^(BOOL completed){ 
    }]; 

    } 
}