切换到另一视图时隐藏键盘

问题描述

| 我在视图上有一些UITextField，当点击它时会弹出键盘。有一个按钮也可以导航到另一个视图。当我在键盘处于活动状态时从此视图导航到第二视图时，会出现问题。当我从第二个视图导航回来时，键盘将独立出现。我该如何预防？

   -(IBAction) loginButton:(id) sender
    {
        [currentTextField resignFirstResponder];
        RequestPage *RequestPageview = [[RequestPage alloc] initWithNibName:nil bundle:nil];


        [UIView beginAnimations:@\"flipping view\" context:nil];
        [UIView setAnimationDuration:1];
        [UIView setAnimationCurve:UIViewAnimationCurveLinear];
        [UIView setAnimationTransition:UIViewAnimationTransitionCurlUp
                               forView:self.view.superview
                                 cache:YES];

        [UIView commitAnimations];
        [self presentModalViewController:RequestPageview animated:YES];
        //ß[self.view addSubview:RequestPageview.view];
    }
//---when the keyboard appears---
-(void) keyboardDidShow:(NSNotification *) notification {
    if (keyboardisShown) return;

    NSDictionary* info = [notification userInfo];

    //---obtain the size of the keyboard---
    NSValue *aValue =
    [info objectForKey:UIKeyboardFrameEndUserInfoKey];
    CGRect keyboardRect =
    [self.view convertRect:[aValue CGRectValue] fromView:nil];


    //---resize the scroll view (with keyboard)---
    CGRect viewFrame = [scrollview frame];
    NSLog(@\"%f\",viewFrame.size.height);
    viewFrame.size.height -= keyboardRect.size.height;
    scrollview.frame = viewFrame;
    NSLog(@\"%f\",keyboardRect.size.height);
    NSLog(@\"%f\",viewFrame.size.height);
    //---scroll to the current text field---
    CGRect textFieldRect = [currentTextField frame];
    [scrollview scrollRectToVisible:textFieldRect animated:YES];
    keyboardisShown = YES;
        NSLog(@\"Login Keyboard appear\");
}

//---when the keyboard disappears---
-(void) keyboardDidHide:(NSNotification *) notification {
    NSDictionary* info = [notification userInfo];

    //---obtain the size of the keyboard---
    NSValue* aValue =
    [info objectForKey:UIKeyboardFrameEndUserInfoKey];
    CGRect keyboardRect =
    [self.view convertRect:[aValue CGRectValue] fromView:nil];


    //---resize the scroll view back to the original size
    // (without keyboard)---
    CGRect viewFrame = [scrollview frame];
    viewFrame.size.height += keyboardRect.size.height;
    scrollview.frame = viewFrame;

    keyboardisShown = NO;
        NSLog(@\"Login Keyboard disappear\");
}


2011-05-27 16:57:20.628 LoginPage[322:207] Login view appear // loaded the app
2011-05-27 16:57:32.220 LoginPage[322:207] Login Keyboard appear // tap on textfield
2011-05-27 16:57:35.665 LoginPage[322:207] Request view appeared // navigate to second view with keyboard shown
2011-05-27 16:57:35.667 LoginPage[322:207] Login view disappear
2011-05-27 16:57:35.978 LoginPage[322:207] Request Keyboard disappear // weird? I should have hide the Login Keyboard instead
2011-05-27 16:57:39.738 LoginPage[322:207] Login view appear // navigate back
2011-05-27 16:57:39.740 LoginPage[322:207] Request view disappeared 

    

解决方法

如果您想在单击按钮时隐藏键盘，并且有多个文本字段，则可以使用此代码...

[self.view endEditing:YES];

点按查看中的任何位置，键盘将消失。 请享用 ！！...     ,在loginButton方法中，在要编辑的文本字段上调用

resignFirstResponder

。当用户导航回到该视图控制器时，键盘将不再存在。您需要稍微更改代码，以便对文本字段进行引用。如果只有一个文本字段，则IBOutlet将起作用。对于多个字段，请以视图控制器为委托，并在用户开始编辑时保留对当前文本字段的引用。您也可以遍历视图的子视图，尽管这样做可能效率不高。