becomeFirstResponder重置contentOffset

Question

我有一个UIScrollView,其中我有一个UITextField,所以我做的是在第三个文本字段,即密码,我向下滚动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,它将内容偏移重置为0,当我这样做时:

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

.我怎样才能防止这种情况发生？

Answer 1

只需在显示键盘之前关闭滚动视图滚动（成为FirstResponder）并在其后启用滚动，

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