IOS開發之－－－鍵盤覆蓋控制項textfield

我們在開發過程中經常會遇到一個問題是，當我們選擇輸入框時會有鍵盤跳出覆蓋了我們的輸入框，這個時候我們需要解決的問題就是：將我們的輸入框上移，使它先是在鍵盤上方：

前提：

在您的h檔案中聲明一個textfield

@property (retain, nonatomic) IBOutlet UITextField *textView;

首先在viewDIdLoad方法中如下：

- (void)viewDidLoad{    [super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardwasShown:) name:UIKeyboardDidShowNotification object:nil];    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardwasHidden:) name:UIKeyboardDidHideNotification object:nil];}

這個方法裡我們調用了兩個方法，一個是鍵盤顯示時的偵聽事件的處理，另一個是鍵盤消失時的偵聽事件的處理。

（1）鍵盤顯示時的偵聽事件的處理

-(void)keyboardwasShown:(NSNotification *) notify{    CGRect frame = [self.view frame];    if ([[notify name]isEqualToString:UIKeyboardDidShowNotification]) {        [UIView animateWithDuration:0.3 animations:^{            self.view.frame = frame;        }completion:^(BOOL finished) {            //        }];    }        NSDictionary *info = [notify userInfo];    NSValue *aValue = [info objectForKey:UIKeyboardFrameBeginUserInfoKey];        CGSize keyBoardSize = [aValue CGRectValue].size;    CGRect rect = self.textView.frame;    rect.origin.y = self.view.frame.size.height - keyBoardSize.height - rect.size.height;    self.textView.frame = rect;    }

（2）鍵盤消失時的偵聽事件的處理

-(void) keyboardwasHidden:(NSNotification *) notify{    NSDictionary *info = [notify userInfo];    NSValue *aValue = [info objectForKey:UIKeyboardFrameEndUserInfoKey];        CGSize keyBoardSize = [aValue CGRectValue].size;            CGRect rect = self.textView.frame;    rect.origin.y = self.view.frame.size.height - rect.size.height;    self.textView.frame = rect;}