iphone sdk - 粘贴到当前文本位置的问题

Question

我试图将文本粘贴到光标当前所在的位置。我一直在努力做到： - http://dev.ragfield.com/2009/09/insert-text-at-current-cursor-location.html

最主要的是，我不能只是去textbox1.text（等），因为文本字段是在自定义单元格的中间。我只想将一些文本添加到光标所在的位置（当我按下键盘上的自定义键时）。

-I只想小数粘贴到文本框...

我得到的错误是：

2010-05-15 22：37：20.797的PageControl [37962：207] * - [MyDetailController paste：]：无法识别的选择器发送到实例0x1973d10 2010-05-15 22：37：20.797 PageControl [37962：207] *由于未捕获异常'NSInvalidArgumentException'而终止应用程序，原因：'*** - [MyDetailController粘贴：]：无法识别的选择器发送到实例0x1973d10'

注：我有机会获得文本字段标签（有没有什么帮助？）

我有点过去在Objective-C初学者阶段，但仍然不是很大。我的代码目前在下面，并在https://gist.github.com/d634329e5ddf52945989

谢谢大家。

---

MyDetailController.h

@interface MyDetailController : UITableViewController <UITextFieldDelegate,UINavigationControllerDelegate> 
{ 

//...(lots in here) 

} 


@end 


@interface UIResponder(UIResponderInsertTextAdditions) 
- (void) insertText: (NSString*) text; 
@end 

---

MyDetailController.m

@implementation MyDetailController 


//.... (lots in here) 



- (void)addDecimal:(NSNotification *)notification { 
    // Apend the Decimal to the TextField. 
    //savedAmount.text = [savedAmount.text stringByAppendingString:@"."]; 

    NSLog(@"Decimal Pressed"); 
    NSLog(@"tagClicked: %d",tagClicked); 
    switch (tagClicked) { 
     case 7: 

      //savedAmount.text = [savedAmount.text stringByAppendingString:@"."]; 
      break; 
     case 8: 
      //goalAmount.text = [goalAmount.text stringByAppendingString:@"."]; 
      break; 
     case 9: 
      //incrementAmount.text = [incrementAmount.text stringByAppendingString:@"."]; 
      break;  
     case 10: 
      //incrementAmount.text = [incrementAmount.text stringByAppendingString:@"."]; 
     break; 
    } 

    [self insertText:@"."]; 
} 

-(void)textFieldDidBeginEditing:(UITextField *)textfield{ 

    //UITextField *theCell = (UITextField *)sender; 
    tagClicked = textfield.tag; 
    NSLog(@"textfield changed. tagClicked: %d",tagClicked); 



} 

@end 

    @implementation UIResponder(UIResponderInsertTextAdditions) 

    - (void) insertText: (NSString*) text 
    { 
     // Get a refererence to the system pasteboard because that's 
     // the only one @selector(paste:) will use. 
     UIPasteboard* generalPasteboard = [UIPasteboard generalPasteboard]; 

     // Save a copy of the system pasteboard's items 
     // so we can restore them later. 
     NSArray* items = [generalPasteboard.items copy]; 

     // Set the contents of the system pasteboard 
     // to the text we wish to insert. 
     generalPasteboard.string = text; 

     // Tell this responder to paste the contents of the 
     // system pasteboard at the current cursor location. 
     [self paste: self]; 

     // Restore the system pasteboard to its original items. 
     generalPasteboard.items = items; 

     // Free the items array we copied earlier. 
     [items release]; 
    } 

    @end 

Answer 1

的UIViewController 是一个UIResponder ......但它不是应该收到insertText：消息的UIResopnder。你想在UITextField本身上调用insertText：如果您在UIResponder.h看看你会看到贴近以下注释：方法

//没有在NSObject的

含义，它并不一定安全，他们只是任何呼吁实施这些方法UIResponder。它们只能在UITextField和UITextView等子类中被安全地调用，并且实际上可以实现它们。这对苹果来说是一个非常奇怪的设计决定。