iPhone xcode - 带有标签栏控制器和多表视图控制器的活动指示器
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iPhone xcode - Activity Indicator with tab bar controller and multi table view controllers
提问by Frames84
I've looked for a tutorial and can't seem to find one for a activity indicator in a table view nav bar. in my mainWindow.xib I have a Tab Bar Controller with 4 Tabs controllers each containing a table view. each load JSON feeds using the framework hosted at Google.
我已经寻找了一个教程，但似乎无法在表格视图导航栏中找到一个活动指示器。在我的 mainWindow.xib 中，我有一个带有 4 个标签控制器的标签栏控制器，每个控制器都包含一个表格视图。每个都使用 Google 托管的框架加载 JSON 提要。
In one of my View Controller I can add an activity indicator to the nav bar by using:
在我的一个视图控制器中，我可以使用以下方法将活动指示器添加到导航栏：
UIActivityIndicatorView *activityIndcator = [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0,0,20,20)];
[activityIndcator startAnimating];
UIBarButtonItem *activityItem = [[UIBarButtonItem alloc] initWithCustomView:activityIndcator];
self.navigationItem.rightBarButtonItem = activityItem;
however and can turn it off by using:
但是，可以使用以下方法将其关闭：
self.navigationItem.rightBarButtonItem.enabled = FALSE;
But if i place this in my viewDidLoad event it shows all the time. I only want it to show when I select a row in my table view. so I added it at the top of didSelectRowAtIndexPath and the stop line after I load a feed. it shows but takes a second or two and only shows for about half a second.
但是如果我把它放在我的 viewDidLoad 事件中，它就会一直显示。我只希望它在我在表格视图中选择一行时显示。所以我在加载提要后将它添加到 didSelectRowAtIndexPath 和停止线的顶部。它显示但需要一两秒钟，并且只显示大约半秒钟。
is the an event that firers before the didSelectRowAtIndexPath event a type of loading event? if not what is the standard menthord for implementing such functionality?
在 didSelectRowAtIndexPath 事件之前触发的事件是一种加载事件吗？如果不是，实现此类功能的标准方法是什么？
回答by Warrior
回答by Rayfleck
In .h file
在 .h 文件中
@property (nonatomic,retain) UIActivityIndicatorView *spinner;
In .m file, @synthesize spinner; // also release in dealloc
在 .m 文件中，@synthesize 微调器；// 也在 dealloc 中释放
In viewDidLoad, do this:
在 viewDidLoad 中，执行以下操作：
UIActivityIndicatorView *activityIndcator = [[UIActivityIndicatorView alloc]
initWithFrame:CGRectMake(0,0,20,20)];
self.spinner = activityIndicator;
spinner.hidesWhenStopped = YES; // this is the default, but never hurts to be sure
UIBarButtonItem *activityItem = [[UIBarButtonItem alloc] initWithCustomView:spinner];
self.navigationItem.rightBarButtonItem = activityItem;
In didSelectRowAtIndexPath, do this:
在 didSelectRowAtIndexPath 中，执行以下操作：
[self.spinner startAnimating];
When feed is done, do this:
进料完成后，请执行以下操作：
[self.spinner stopAnimating];
