NSHUDWindowMaskなNSPanelを生成する方法

Interface Builderを使わずにWindowを表示する一例（？）
僕は本格的にCocoaを触り始めて一週間弱のビギナーですので、予めそのことをご了承ください。

ポイント

styleMaskの "NSHUDWindowMask" は NSWindow には設定出来ないので、NSPanelを継承したクラスを作る（この例では hudWindow）
（NSPanel及びNSHUDWindowMaskについてはこちらを参照：http://developer.apple.com/mac/library/documentation/Cocoa/Reference/ApplicationKit/Classes/NSPanel_Class/Reference/Reference.html）

TestAppDelegate.h

#import <Cocoa/Cocoa.h>

@interface TestAppDelegate : NSObject <NSApplicationDelegate> 
{
    NSPanel *hudWindow;

    NSButton    *hudButton;
    NSTextField *hudTextField;
}

@property (assign) IBOutlet NSWindow *window;

- (void)processAction:(id)sender;

@end

TestAppDelegate.m

#import "TestAppDelegate.h"


@implementation TestAppDelegate

@synthesize window;


- (void)applicationDidFinishLaunching:(NSNotification *)aNotification 
{
    NSScreen *mainScreen = [NSScreen mainScreen];

    hudWindow = [[NSPanel alloc] 
        initWithContentRect:NSMakeRect(100, 100, 300, 44) 
                  styleMask:NSResizableWindowMask|NSHUDWindowMask|NSUtilityWindowMask|NSClosableWindowMask 
                    backing:NSBackingStoreRetained
                      defer:NO 
                     screen:mainScreen];

    // =============================================================================

    hudTextField = [[NSTextField alloc] initWithFrame:NSMakeRect(10, 10, 180, 24)];
    [hudTextField setObjectValue:@"Hello HUDWindow"];
    [hudTextField setEditable:YES];
    [hudTextField setTarget:self];
    [hudTextField setAction:@selector(processAction:)];

    [[hudWindow contentView] addSubview:hudTextField];
    [hudTextField release];


    hudButton = [[NSButton alloc] initWithFrame:NSMakeRect(200, 10, 80, 24)];
    [hudButton setTitle:@"Click Me"];
    [hudButton setTarget:self];
    [hudButton setAction:@selector(processAction:)];
    [hudButton setBezelStyle:NSRoundRectBezelStyle];    

    [[hudWindow contentView] addSubview:hudButton];
    [hudButton release];

    // =============================================================================

    [hudWindow setTitle:@"NSHUDWindow styleMask Test"];
    [hudWindow setDisplaysWhenScreenProfileChanges:YES];
    [hudWindow makeKeyAndOrderFront:self];
}

- (void)processAction:(id)sender
{
    NSLog(@"TestAppDelegate::processAction");
    NSLog(@"%@", [hudTextField objectValue]);
}