来自 NSMenuItem (Button) 的 NSPopover 不接受鼠标事件

Question

我想知道是否有人知道为什么当从 NSMenu 内的 NSMenuItem 内的按钮打开 NSPopover 时，它不响应鼠标事件（悬停、单击）。

如果有解决这个问题的方法？

这是一个将 NSMenu 附加到其视图的小示例视图控制器。该菜单有一个按钮，可在单击时打开弹出框，以及一些虚拟项目，即使弹出框位于它们上方，它们仍会显示它们仍然接收鼠标事件：

@implementation MyViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    NSMenu *menu = [NSMenu new];
    /// Some Dummy Items to show that the popover doesn’t accept the mouse.
    NSArray *dummyItems = @[@"item1", @"item2", @"item3"];
    for (NSString *itemName in dummyItems) {
        NSMenuItem *item = [NSMenuItem new];
        item.title = itemName;
        item.target = self;
        item.action = @selector(doNothing:);
        [menu addItem:item];
    }
    
    /// The button which presents the popover on click
    NSMenuItem *item = [NSMenuItem new];
    NSButton *button = [[NSButton alloc] initWithFrame:NSMakeRect(0, 0, 100, 30)];
    button.target = self;
    button.action = @selector(showPopover:);
    button.title = @"Show Popover";
    item.view = button;
    [menu addItem:item];
    
    [self.view setMenu:menu];
}

- (void)showPopover:(NSButton *)sender {
    /// This popover does not receive the mouse events for some reason.
    NSPopover *popover = [NSPopover new];
    NSViewController *popoverVC = [NSViewController new];
    NSButton *button = [[NSButton alloc] initWithFrame:NSMakeRect(0, 0, 140, 25)];
    button.title = @"I’m not clickable";
    button.target = self;
    button.action = @selector(showPopover:);
    popoverVC.view = button;
    [popover setContentViewController:popoverVC];
    [popover showRelativeToRect:sender.frame ofView:sender.superview preferredEdge:NSMaxYEdge];
    [button.window makeKeyWindow];   /// Does not help
    [button.window becomeKeyWindow]; /// Does not help
}

- (void)doNothing:(id)sender {}

@end

Answer 1

有一个解决方案，但它可能没有用，具体取决于您要执行的操作。我无法运行您发布的代码，但可以看到您在菜单和弹出窗口中都添加了一个按钮。问题似乎是用于显示弹出框的矩形。由于我不知道的原因，如果我们尝试根据菜单项按钮的框架显示弹出框，则无法单击弹出框按钮。但是，如果弹出框显示基于基于窗口 contentView 的控件的框架，例如 NSPopUpButton 或位于菜单附近的 NSView 的矩形，则弹出框按钮将变为可点击。由于附近没有矩形，从菜单栏中删除的菜单更具挑战性。通过删除预先存在的 main.m 代码并将以下内容复制/粘贴到其中，可以在 Xcode objc 项目中运行此演示。还需要删除预先存在的 AppDelegate 文件以避免重复符号。该演示说明了使用 NSView 矩形和 NSPopUpButton 框架来显示弹出框，其中任何一个都将允许可点击的弹出框按钮。失败的代码会被移除。

#import <Cocoa/Cocoa.h>

@interface PopoverController: NSViewController
@end

@implementation PopoverController
@end


@interface AppDelegate : NSObject <NSApplicationDelegate> {
 NSWindow *window;
 NSPopover *popover;
 NSView *popoverView;
 NSMenuItem *menuItem;
 NSMenu *menu;
 PopoverController *popoverController;
 NSPopUpButton *pullDwn;
 NSView *menuView;
}

- (void) showPopoverAction:(id)sender;
- (void) menuAction:(id)sender;
- (void) myBtnAction:(id)sender;
- (void) buildMenu;
- (void) buildWnd;
@end

@implementation AppDelegate


- (void) showPopoverAction:(id)sender {
// **** This works **** //
//[popover showRelativeToRect:pullDwn.bounds ofView:pullDwn preferredEdge:NSMaxXEdge];
[popover showRelativeToRect:menuView.bounds ofView:menuView preferredEdge:NSMaxXEdge];
// **** This doesn't **** //
//[popover showRelativeToRect:[menuItem.view bounds] ofView:menuItem.view preferredEdge:NSMaxXEdge];
}

- (void) myBtnAction: (id)sender {
 NSBeep();
 NSLog(@"Popover button hit.");
 NSLog(@"===================");
}

- (void) menuAction: (id)sender {
[popover showRelativeToRect:pullDwn.bounds ofView:pullDwn preferredEdge:NSMaxXEdge];
}

- (void) buildMenu {
 NSMenu *menubar = [NSMenu new];
 NSMenuItem *menuBarItem = [NSMenuItem new];
 [menubar addItem:menuBarItem];
 [NSApp setMainMenu:menubar];
 NSMenu *appMenu = [NSMenu new];
 NSMenuItem *quitMenuItem = [[NSMenuItem alloc] initWithTitle:@"Quit" action:@selector(terminate:) keyEquivalent:@"q"];
 [appMenu addItem:quitMenuItem];
 [menuBarItem setSubmenu:appMenu];
}

- (void) buildWnd {

#define _wndW  500
#define _wndH  350

window = [[NSWindow alloc] initWithContentRect: NSMakeRect( 0, 0, _wndW, _wndH )
styleMask: NSWindowStyleMaskTitled | NSWindowStyleMaskMiniaturizable | NSWindowStyleMaskClosable | NSWindowStyleMaskResizable
backing: NSBackingStoreBuffered defer: NO];

[window center];
[window setTitle: @"NSPopUpButton Menu"];
[window makeKeyAndOrderFront: nil];

// ******* Popover controller ********* //
popoverController = [[PopoverController alloc] init];

// **** Menu View **** //
menuView = [[NSView alloc]initWithFrame:NSMakeRect( 100, _wndH - 242, 130, 30 ) ];
[[window contentView] addSubview:menuView];

// ****** Pull-Down NSPopUpButton ******* //
// First array element (0) becomes the title
NSArray *menuItems = [NSArray arrayWithObjects: @"Pull-Down", @"Item 1", @"Item 2",@"Item 3",nil];
pullDwn = [[NSPopUpButton alloc] initWithFrame:NSMakeRect( 100, _wndH - 142, 130, 30 )];
 menu = pullDwn.menu;
 menuItem = [NSMenuItem new];
 NSButton *myBtn =[[NSButton alloc]initWithFrame:NSMakeRect( 30, 30, 95, 30 )];
[myBtn setBezelStyle:NSBezelStyleRounded ];
[myBtn setTitle: @"Popover"];
[myBtn setAction: @selector (showPopoverAction:)];
menuItem.view = myBtn;
[pullDwn setPullsDown:YES];
[pullDwn addItemsWithTitles:menuItems];
[pullDwn setTarget:self];
[pullDwn setAction:@selector(menuAction:)];
[menu addItem:menuItem];
[[window contentView]addSubview:pullDwn];

// **** NSPopover **** //
 popover = [[NSPopover alloc] init];
 [popover setContentViewController:popoverController];
 [popover setContentSize:NSMakeSize(150, 100)];
 //[popover setBehavior:NSPopoverBehaviorTransient];
 [popover setBehavior:NSPopoverBehaviorSemitransient];
 //[popover setBehavior:NSPopoverBehaviorApplicationDefined];
 [popover setAnimates: YES];
 [popover setDelegate: self];
 
// ****** Popover view ****** //
 popoverView = [[NSView alloc] initWithFrame:NSMakeRect(0, 0, 150, 100)];

//******* Popover text field ******* //
NSTextField *ef = [[NSTextField alloc] initWithFrame:NSMakeRect( 20, 20, 110, 24 )];
[ef setStringValue:@"EditFld"];
[ef setAlignment:NSTextAlignmentCenter];
[ef setDrawsBackground:NO];
[popoverView addSubview:ef];

// **** Popover Button **** //
NSButton *popoverBtn =[[NSButton alloc]initWithFrame:NSMakeRect( 20, 50, 95, 24 )];
[popoverBtn setBezelStyle:NSBezelStyleRounded ];
[popoverBtn setTitle: @"Push me"];
popoverBtn.target = self;
popoverBtn.action = @selector(myBtnAction:);
[popoverView addSubview: popoverBtn];
[popoverController setView:popoverView];

// ***** Quit btn ***** //
NSButton *quitBtn = [[NSButton alloc]initWithFrame:NSMakeRect( _wndW - 50, 5, 40, 40 )];
[quitBtn setBezelStyle:NSBezelStyleCircular ];
[quitBtn setTitle: @"Q" ];
[quitBtn setAutoresizingMask: NSViewMinXMargin];
[quitBtn setAction:@selector(terminate:)];
[[window contentView] addSubview: quitBtn];
}

- (void) applicationWillFinishLaunching: (NSNotification *)notification {
[self buildMenu];
[self buildWnd];
}

- (void) applicationDidFinishLaunching: (NSNotification *)notification {
}
@end

int main () {
NSApplication *application = [NSApplication sharedApplication];
AppDelegate *appDelegate = [[AppDelegate alloc] init];
[application setDelegate:appDelegate];
[application run];
return 0;
}