我需要隐藏导航栏中的右键,然后在用户选择一些选项后取消隐藏。
很遗憾,以下方法不起作用:
NO GOOD: self.navigationItem.rightBarButtonItem.hidden = YES; // FOO CODE
有办法吗?
最佳答案
通过将引用设置为 nil 来隐藏按钮,但是如果您想稍后恢复它,您需要保留它的副本以便重新分配它。
UIBarButtonItem *oldButton = self.navigationItem.rightBarButtonItem;
[oldButton retain];
self.navigationItem.rightBarButtonItem = nil;
//... later
self.navigationItem.rightBarButtonItem = oldButton;
[oldButton release];
就个人而言,在我的应用程序中,我将导航按钮设置为 @properties,以便我可以随意丢弃和重新创建它们,例如:
//mycontroller.h
UIBarButtonItem *rightNavButton;
@property (nonatomic, retain) UIBarButtonItem *rightNavButton;
//mycontroller.m
@synthesize rightNavButton;
- (UIBarButtonItem *)rightNavButton {
if (!rightNavButton) {
rightNavButton = [[UIBarButtonItem alloc] init];
//configure the button here
}
return rightNavButton;
}
//later, in your code to show/hide the button:
self.navigationItem.rightBarButtonItem = self.rightNavButton;
https://stackoverflow.com/questions/5588767/