Question

如果你这样调用TransformProcessType（）：

ProcessSerialNumber psn = { 0, kCurrentProcess }; 
(void) TransformProcessType(&psn, kProcessTransformToForegroundApplication);

然后cocoa应用程序菜单不显示，除非你在应用程序中尽早调用它（例如在applicationWillFinishLaunching中）。

Answer 1

我向Apple寻求帮助，他们帮助我很好。引用：

调用TransformProcessType时未显示菜单栏的原因是您的应用程序已经是活动应用程序（即[[NSRunningApplication currentApplication] isActive]返回YES）并且当应用程序的菜单栏显示时该应用已已激活

这是他们的解决方法：

- (void)transformStep1 {
    for (NSRunningApplication * app in [NSRunningApplication runningApplicationsWithBundleIdentifier:@"com.apple.finder"]) {
        [app activateWithOptions:NSApplicationActivateIgnoringOtherApps];
        break;
    }
    [self performSelector:@selector(transformStep2) withObject:nil afterDelay:0.1];
}

- (void)transformStep2
{
    ProcessSerialNumber psn = { 0, kCurrentProcess }; 
    (void) TransformProcessType(&psn, kProcessTransformToForegroundApplication);

    [self performSelector:@selector(transformStep3) withObject:nil afterDelay:0.1];
}

- (void)transformStep3
{
    [[NSRunningApplication currentApplication] activateWithOptions:NSApplicationActivateIgnoringOtherApps];
}

Answer 2

以下是我如何使其发挥作用。

BOOL MakeAppForeground()
{
    BOOL bSuccess = TranformAppToState(kProcessTransformToForegroundApplication);

    if(bSuccess)
    {
         bSuccess = (SetSystemUIMode(kUIModeNormal, 0) == 0);
        [NSApp activateIgnoringOtherApps:YES];
    }

    return bSuccess;
}

BOOL MakeAppBackground()
{
    return TranformAppToState(kProcessTransformToBackgroundApplication);
}

BOOL TranformAppToState(ProcessApplicationTransformState newState)
{
    ProcessSerialNumber psn = { 0, kCurrentProcess };
    OSStatus transformStatus = TransformProcessType(&psn, newState);

    if((transformStatus != 0))
    {
        NSError *error = [NSError errorWithDomain:NSOSStatusErrorDomain code:transformStatus userInfo:nil];
        NSLog(@"TranformAppToState: Unable to transform App state. Error - %@",error);
    }

    return (transformStatus == 0);
}

调用TransformProcessType（）时，应用程序菜单不会显示

2 个答案: