Question

在我的应用程序中，我有一些通过键盘填充的文本字段。其中有6个，最后两个位于屏幕的最底部，只要键盘出现就会隐藏。有什么建议??

Answer 1

使用UIScrollview以便用户向下滚动。您可以使用UITextField的inputAccessoryView来显示下一个和上一个按钮，点击让输入跳转到下一个文本字段并滚动到它。

在SO处查看此question and answers，同样的问题，不同的解决方案。

Answer 2

将textFields委托为self，并将以下代码添加到textFieldDidBeginEditing和textFieldDidEndEditing。

定义以下常量:(已为iPad设置常量。为iphone调整它们）

static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.3;
static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 302;

在班级的.h文件中添加两个变量。 CGFloat animatedDistance;和UITextField * currentField;

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

    currentField = textField;
    UIInterfaceOrientation orientation =
    [[UIApplication sharedApplication] statusBarOrientation];

    CGRect textFieldRect =[self.view.window convertRect:textField.bounds fromView:textField];

    CGRect viewRect =[self.view.window convertRect:self.view.bounds fromView:self.view];
    if (orientation == UIInterfaceOrientationLandscapeLeft )
    {
        textFieldRect.origin.y = textFieldRect.origin.x;
        textFieldRect.size.height = textFieldRect.size.width;
        viewRect.size.height = viewRect.size.width;
    }
    else  if (orientation == UIInterfaceOrientationLandscapeRight )
    {
        textFieldRect.origin.y =viewRect.size.width - textFieldRect.origin.x;
        textFieldRect.size.height = textFieldRect.size.width;
        viewRect.size.height = viewRect.size.width;
    }
    else   if (orientation == UIInterfaceOrientationPortraitUpsideDown)
    {
        textFieldRect.origin.y = viewRect.size.height - textFieldRect.origin.y;
    }

    CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
    CGFloat numerator = midline - viewRect.origin.y - MINIMUM_SCROLL_FRACTION * viewRect.size.height;
    CGFloat denominator =(MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)* viewRect.size.height;
    CGFloat heightFraction = numerator / denominator;
    if (heightFraction < 0.0)
    {
        heightFraction = 0.0;
    }
    else if (heightFraction > 1.0)
    {
        heightFraction = 1.0;
    }
    if (orientation == UIInterfaceOrientationPortrait ||
        orientation == UIInterfaceOrientationPortraitUpsideDown)
    {
        animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
    }
    else
    {
        animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
    }
    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y -= animatedDistance;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

    [self.view setFrame:viewFrame];

    [UIView commitAnimations];

}


- (void)textFieldDidEndEditing:(UITextField *)textField {

    [textField resignFirstResponder];

    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y += animatedDistance;

    animatedDistance = 0;
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

    [self.view setFrame:viewFrame];

    [UIView commitAnimations];

    currentField = nil;
}

如何在键盘出现时将我的视图拖动一点？

2 个答案: