如何从其他类（NSViewController的子类）获取主窗口（应用程序委托）？ [英] How to get Main Window (App Delegate) from other class (subclass of NSViewController)?

问题描述

我想改变我的Windows内容，从其他类，这是NSViewController的子类。我尝试下面的代码，但它不做任何事情。

  [NSApplication sharedApplication] mainWindow] setContentView：[self view]]; // NSViewController中的代码
 
 [NSApplication sharedApplication] mainWindow] //返回null 
  

我试图添加

  [window makeMainWindow];应用程序代理类中的
  

，但不会有帮助。

我错过了什么吗？

还有我使用下面的代码调用任何委托函数在我的类，

  [（appDelegate *）[[NSApplication sharedApplication] delegate] MyMethod]; 
  

但我不知道有没有更好的东西，wihtout导入委托类。类似这样的

  [[NSApplication sharedApplication] delegate] MyMethod]; 
  

解决方案

$ b 这个方法可能返回nil，如果

我刚刚创建了一个应用程序的nib文件没有完成加载，如果接收者没有激活，快速测试应用程序，我放置了以下代码：

  NSLog（@％@，[[NSApplication sharedApplication] mainWindow] ; 
  

到我的 applicationDidFinishLaunching：aNotification 到我的应用程序的主窗口中的一个按钮。

在启动时， mainWindow 是nil，但是当我点击按钮（一切都开始运行并显示后）， mainWindow 不再为nil。

NSApplication 提供您可能对您有用的其他方法：

• - windows - 所有窗口的数组;


• - keyWindow - 给出正在接收键盘输入（或nil）的窗口;


• - windowWithWindowNumber： - 返回与窗口编号 - 如果您知道您要替换的窗口的编号，您可以使用此窗口编号;


• - makeWindowsPerform：inOrder： - 向每个窗口发送一条消息 - 您可以使用它来测试每个窗口，看看它是否是您感兴趣的窗口。

关于委托的调用方法，你说的警告对我来说工作正常。例如，这没有警告：

  NSLog（@％@，[[[NSApplication sharedApplication] delegate] ]）; 
  

您收到的警告到底是什么？您尝试调用不存在的方法？

I'm trying to change my windows content, from other class , that is subclass of NSViewController.I'm trying code below, but it doesn't do anything.

[NSApplication sharedApplication]mainWindow]setContentView:[self view]]; //code in NSViewController

[NSApplication sharedApplication]mainWindow] // returns null

I tried to add

[window makeMainWindow];

in App Delegate class, but it won't help.

Did I miss something?

P.S. Also I'm using code below to call any delegate function in my class,

 [(appDelegate *) [[NSApplication sharedApplication]delegate]MyMethod];

but I wonder is there something better, wihtout importing delegate class. Something like this

[[NSApplication sharedApplication]delegate]MyMethod];

(it gives warning)

解决方案

For the mainWindow method the docs say:

This method might return nil if the application’s nib file hasn’t finished loading, if the receiver is not active, or if the application is hidden.

I just created a quick test application and I placed the following code:

NSLog(@"%@", [[NSApplication sharedApplication] mainWindow]);

into my applicationDidFinishLaunching:aNotification method, and into an action method which I connected to a button in the main window of my application.

On startup, the mainWindow was nil, but when I click the button (after everything is up and running and displayed), the mainWindow was no longer nil.

NSApplication provides other methods which you may be useful to you:

• - windows - an array of all the windows;
• – keyWindow - gives the window that is receiving keyboard input (or nil);
• – windowWithWindowNumber: - returns a window corresponding to the window number - if you know the number of the window whose contents you wish to replace you could use this;
• – makeWindowsPerform:inOrder: - sends a message to each window - you could use this to test each window to see if it's the one you are interested in.

With regard to calling methods on the delegate, what you say gives a warning works fine for me. For example, this works with no warnings:

NSLog(@"%@", [[[NSApplication sharedApplication]delegate] description]);

What exactly is the warning you receive? Are you trying to call a method that doesn't exist?

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