becomeFirstResponder重置contentOffset

Question

我有一个UIScrollView，里面有一个UITextField，所以我所做的就是在第三个文本字段，即密码，向下滚动UIScrollView的偏移量：

#pragma mark UITextFieldDelegate
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    if ((textField == self.emailTextField_ || textField == self.passwordTextField_)){
        if (self.scrollView_.contentOffset.y != self.emailTextField_.frameY - self.emailTextField_.frameHeight/2){
            shouldAdjustOffset = YES;
        } else {
            shouldAdjustOffset = NO;
        }

        if (shouldAdjustOffset){
            [self.scrollView_ setContentOffset:CGPointMake(0, self.emailTextField_.frameY - self.emailTextField_.frameHeight/2) animated:YES];
        }
    }
}

-(BOOL) textFieldShouldReturn:(UITextField *)textField
{
    if (textField == self.firstNameTexField_){
        [self.firstNameTexField_ resignFirstResponder];
        [self.lastNameTextField_ becomeFirstResponder];
    } else if (textField == self.lastNameTextField_){
        [self.lastNameTextField_ resignFirstResponder];
        [self.emailTextField_ becomeFirstResponder];
    } else if (textField == self.emailTextField_){
        [self.emailTextField_ resignFirstResponder];
        [self.passwordTextField_ becomeFirstResponder];
    } else if (textField == self.passwordTextField_){
        [self signupButtonPressed:nil];
        [self.passwordTextField_ resignFirstResponder];
    }

    return YES;
}

现在的问题是，当我在下一个文本字段时，它会将内容偏移量重置回0，当我这样做时：

 [self.emailTextField_ resignFirstResponder];
        [self.passwordTextField_ becomeFirstResponder];

。我如何才能防止这种情况发生？

Answer 1

只需在显示键盘(becomeFirstResponder)前打开scrollview scroll，并在它之后启用回滚，

scrollView.scrollEnabled = NO;
[someControl becomeFirstResponder];
scrollView.scrollEnabled = YES;
[scrollview doTheScrollingHere];

Answer 2

@Deepan你为我节省了很多时间:)我只建议重写UITextField方法becomeFirstResponder，首先检查它是否在UIScrollView中，如果是禁用滚动一段时间

- (BOOL)becomeFirstResponder
{
    if ([self.superview isKindOfClass:[UIScrollView class]])
    {
        [(UIScrollView*)self.superview setScrollEnabled:NO];
    }

    BOOL accept = [super becomeFirstResponder];

    if ([self.superview isKindOfClass:[UIScrollView class]])
    {
        [(UIScrollView*)self.superview setScrollEnabled:YES];
    }

    return accept
}