Objective c NSUndoManager基础知识
我制作了一个应用程序,它有一个按钮,当你按下它时,它将被禁用,撤消操作将使它返回到以前的状态(启用它)。我使用NSUndoManager使这成为可能,但它不起作用。看起来我的应用程序中缺少了一些重要的东西,但我找不到确切的内容 AppDelegate.h:Objective c NSUndoManager基础知识,objective-c,xcode,undo,nsundomanager,Objective C,Xcode,Undo,Nsundomanager,我制作了一个应用程序,它有一个按钮,当你按下它时,它将被禁用,撤消操作将使它返回到以前的状态(启用它)。我使用NSUndoManager使这成为可能,但它不起作用。看起来我的应用程序中缺少了一些重要的东西,但我找不到确切的内容 AppDelegate.h: #import <Cocoa/Cocoa.h> @interface AppDelegate : NSObject <NSApplicationDelegate> { NSUndoManager* undoM
#import <Cocoa/Cocoa.h>
@interface AppDelegate : NSObject <NSApplicationDelegate>
{
NSUndoManager* undoManager;
}
@property (assign) IBOutlet NSWindow *window;
@property (weak) IBOutlet NSButton *button;
- (IBAction)Disable:(id)sender;
@end
我做错了什么?我已经编辑了您的代码,希望我的示例能对您有所帮助 如果仍有问题,请通知我=)
#import "AppDelegate.h"
@implementation AppDelegate
@synthesize window = _window;
- (NSUndoManager*)windowWillReturnUndoManager:(NSWindow*)window
{
return undoManager;
}
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
}
- (id) init
{
if(self = [super init])
undoManager = [[NSUndoManager alloc]init];
return self;
}
- (IBAction)Disable:(id)sender
{
[[undoManager prepareWithInvocationTarget:self]Enable];
[_button setEnabled:NO];
if (![undoManager isUndoing])
[undoManager setActionName:@"Disable"];
}
-(void)Enable
{
[[undoManager prepareWithInvocationTarget:self]Disable:self];
[_button setEnabled:YES];
if (![undoManager isUndoing])
[undoManager setActionName:@"Enable"];
}
@end
#import "AppDelegate.h"
@interface AppDelegate ()
{
NSUndoManager* undoManager;
}
@property (weak) IBOutlet NSWindow *window;
@property (weak) IBOutlet NSButton *button;
@property (weak) IBOutlet NSButton *undoButton;
@end
@implementation AppDelegate
- (NSUndoManager*)windowWillReturnUndoManager:(NSWindow*)window
{
return undoManager;
}
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
undoManager = [[NSUndoManager alloc]init];
[self update];
}
- (IBAction)Disable:(id)sender
{
[[undoManager prepareWithInvocationTarget:self]Enable];
[_button setEnabled:NO];
if (![undoManager isUndoing])
[undoManager setActionName:@"Disable"];
[self update];
}
- (IBAction)undo:(id)sender
{
[undoManager undo];
[self update];
}
-(void)Enable
{
[[undoManager prepareWithInvocationTarget:self]Disable:self];
[_button setEnabled:YES];
if (![undoManager isUndoing])
[undoManager setActionName:@"Enable"];
[self update];
}
- (void)update
{
self.undoButton.title = [undoManager canUndo]?@"Undo":@"Can't undo";
}
@end