Question

我使用以下方法点击位于我的OS X应用程序主窗口的NSButton (openPane l）以显示NSPanel (myPanel）：

- (IBAction)openPanel:(id)sender {
    [_myPanel makeKeyAndOrderFront:nil];
}

一切都按预期工作，除了我第一次单击按钮（openPanel）时在调试区域中得到以下描述：

"unlockFocus called too many times. Called on NSButton: 0x610000141080."

Panel的属性选择如下：

Style: Utility Panel, 
Appearance:Title Bar and Shadow, 
Controls:  Close, 
Behaviour: Restorable, 
Memory: Deferred

我查看了网页但找不到任何解释。有谁知道为什么会这样或者如何解决它？

Answer 1

I had the same problem using XCode 7.0 beta 6 using storyboards and a segue to display a sheet. It seems some common problem which happens if you open the panel directly from the action.

To solve the problem, just open the panel from the main queue:

- (IBAction)openPanel:(id)sender {
    dispatch_async(dispatch_get_main_queue(), ^{
        [_myPanel makeKeyAndOrderFront:nil];
    });
}

This will also solve similar problems from swift and storyboards. Use this swift code to call a segue:

@IBAction func onButtonClicked(sender: AnyObject) {
    dispatch_async(dispatch_get_main_queue(), {
        self.performSegueWithIdentifier("identifier", sender: self);
    })
}

Answer 2

不确定那里发生了什么，但我会尝试这个来展示你的NSPanel：

-(IBAction)openPanel:(id)sender {
[[NSApplication sharedApplication] beginSheet:_myPanel
                               modalForWindow:self.window
                                modalDelegate:self
                               didEndSelector:@selector(sheetDidEnd:returnCode:contextInfo:)
                                  contextInfo:nil];

此外，您应确保为您的NSPanel激活关闭后释放复选框。在Interface Builder中搜索它。

编辑：你在NSPanel上画画了吗？设置NSColor或显示NSImage？我的猜测是你正在显示一个NSImage并且搞砸了一些事情：Apple Doc: lockFocus

Answer 3

我已修复了以下

的相同问题

在标题中

@interface aWindowController : NSWindowController
{
    /* other Vars */

    NSOpenPanel *panel;
}

在.m

- (void)windowDidLoad {
    [super windowDidLoad];

    /* other stuff */

    /* set Panel Properties */
    panel = [NSOpenPanel openPanel];

    [panel setCanChooseDirectories:YES];
    [panel setCanChooseFiles:NO];
    [panel setAllowsMultipleSelection:YES];
}

NSButton IBACTION中的

- (IBAction)getFiles:(id)sender
{
    NSArray *resultArry;

    if([panel runModal] == NSFileHandlingPanelOKButton ){
        resultArry = [panel URLs];
        return resultArry;
    }

    return nil;
}

ARC将清理面板。

Answer 4

我遇到了一个叫做Segue的NSPopUpButton同样的问题，而@Flovdis的答案对我有用。

这是我使用的Objective C代码：

dispatch_async(dispatch_get_main_queue(), ^{
        [self performSegueWithIdentifier:@"MySegue" sender:self];
    });

unlockFocus调用次数太多了

4 个答案: