iphone - UIActionSheet 需要很长时间才能响应

Question

我正在 actionSheet:clickedButtonAtIndex 委托(delegate)方法上创建一个 UIActionSheet。

- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex     
 if(buttonIndex == 1){

        [self.myFirstView removeFromSuperview]; 

        if (!self.mySecondView) {
            [[NSBundle mainBundle] loadNibNamed:@"MySecondView" owner:self options:nil];
        }
        [self.mySecondView setFrame:CGRectMake(0, 0, 320, 480)];

        [[UIApplication sharedApplication].keyWindow addSubview: self.mySecondView];

        UIActionSheet * action = [[UIActionSheet alloc]initWithTitle:@""
                                                            delegate:self
                                                   cancelButtonTitle: nil
                                              destructiveButtonTitle: deleteContacts
                                                   otherButtonTitles: cancel, nil];
        action.tag = 102;
        [action showInView:self.view];
        [action release];

    }

我用与上面完全相同的方法处理此 UIActionSheet 的点击事件。

if(actionSheet.tag == 102){

    if(buttonIndex == 0){
        if([[NSBundle mainBundle] loadNibNamed:@"MyThirdView" owner:self options:nil]) { 
            [self.myThirdView setFrame:CGRectMake(0, 0, 320, 480)];
            [[UIApplication sharedApplication].keyWindow addSubview:self.myThirdView];
        }
        [self.mySecondView removeFromSuperview]; 

        [self.doneButton.target performSelector:self.doneButton.action withObject:self.doneButton.target];

        [self performSelector:@selector(RemoveView) withObject:self afterDelay:3.0];

    }
}

我面临的问题是，UIActionSheet 响应时间过长。当我单击 UIActionSheet 按钮时，它会在 myThirdView 加载之前处于卡住状态 2 或 3 秒。我无法理解，在这种情况下，响应延迟是多少，因为我在 UIActionSheet 按钮单击事件方法中做的第一件事是加载 myThirdView。其余代码仅在加载 myThirdView 的代码之后执行。但即使是第一行代码似乎也要延迟执行。 有什么建议吗？

Answer 1

这可能是因为这个

[self performSelector:@selector(RemoveView) withObject:self afterDelay:3.0];

制作其他方法并在该方法中执行此操作。像这样

[self viewRemover];

在 viewRemover 中

-(void) viewRemover
{
    [self performSelector:@selector(RemoveView) withObject:self afterDelay:3.0];

}

所以你的代码现在是这样的

if(actionSheet.tag == 102){

    if(buttonIndex == 0){
        if([[NSBundle mainBundle] loadNibNamed:@"MyThirdView" owner:self options:nil]) { 
            [self.myThirdView setFrame:CGRectMake(0, 0, 320, 480)];
            [[UIApplication sharedApplication].keyWindow addSubview:self.myThirdView];
        }
        [self.mySecondView removeFromSuperview]; 

        [self.doneButton.target performSelector:self.doneButton.action withObject:self.doneButton.target];

    [self performSelectorInBackground:@selector(viewRemover) withObject:nil];

    }
}