NSOpenPanel - 不推薦使用？

Question

我一直試圖讓一個窗口出現，要求人選擇一個文件，我最終做到了。問題是，Xcode抱怨我正在使用的方法已被棄用。我查看了class reference，但在「運行面板」部分下的所有內容在Mac OS 10.6以前都已棄用。我現在應該使用不同的課程嗎？

Answer 1

據我所知，您可以使用runModal方法如下所示：

NSOpenPanel *openPanel = [[NSOpenPanel alloc] init]; 

if ([openPanel runModal] == NSOKButton) 
{ 
    NSString *selectedFileName = [openPanel filename]; 
} 

Answer 2

在10.6，有這個班的幾個變化。其中一個好處是現在有一個基於塊的API。

下面是如何使用的代碼片段：

NSOpenPanel *panel = [[NSOpenPanel openPanel] retain]; 

// Configure your panel the way you want it 
[panel setCanChooseFiles:YES]; 
[panel setCanChooseDirectories:NO]; 
[panel setAllowsMultipleSelection:YES]; 
[panel setAllowedFileTypes:[NSArray arrayWithObject:@"txt"]]; 

[panel beginWithCompletionHandler:^(NSInteger result){ 
    if (result == NSFileHandlingPanelOKButton) { 

     for (NSURL *fileURL in [panel URLs]) { 
      // Do what you want with fileURL 
      // ... 
     } 
    } 

    [panel release]; 
}]; 

Answer 3

看到我是如何發現這個問題有用的六年後，由於沒有迅速的答案，這裏有一個快速的解決方案。

您會發現兩個樣本，一個作爲獨立窗口，另一個作爲工作表。

雨燕3.0

func selectIcon() { 
    // create panel 
    let panel = NSOpenPanel() 

    // configure as desired 
    panel.canChooseFiles = true 
    panel.canChooseDirectories = false 
    panel.allowsMultipleSelection = false 
    panel.allowedFileTypes = ["png"] 

    // *** ONLY USE ONE OF THE FOLLOWING OPTIONS, NOT BOTH *** 

    // ********************** OPTION 1 *********************** 
    // use this if you want a selection window to display that is 
    // displayed as a separate stand alone window 
    panel.begin { [weak self] (result) in 
     guard result == NSFileHandlingPanelOKButton, panel.urls.isEmpty == false, let url = panel.urls.first else { 
      return 
     } 

     let image = NSImage.init(contentsOf: url) 
     DispatchQueue.main.async { 
      self?.iconImageView.image = image 
     } 
    } 

    // ********************** OPTION 2 ***********************   
    // use this if you want a sheet style view that displays sliding 
    // down from your apps window 
    panel.beginSheetModal(for: self.view.window!) { [weak self] (result) in 
     guard result == NSFileHandlingPanelOKButton, panel.urls.isEmpty == false, let url = panel.urls.first else { 
      return 
     } 

     let image = NSImage.init(contentsOf: url) 
     DispatchQueue.main.async { 
      self?.iconImageView.image = image 
     } 
    } 
}