Question

我想在焦点在表格视图单元格中的文本框时滚动视图。我想得到文本字段的y，目前我按照单元格检索。但我认为，按照观点。

目前我对这些值进行了硬编码。

CGRect aRect = self.view.frame;

aRect.size.height -= kbSize.height;
CGRect cellRect = activeField.frame;
cellRect.origin.y = 350;

if (!CGRectContainsPoint(aRect, cellRect.origin) ) {

    CGPoint scrollPoint = CGPointMake(0.0, cellRect.origin.y - kbSize.height);

    [scrollView setContentOffset:scrollPoint animated:YES];

}

根据视图，是否有任何可能获得文件高度。

Answer 1

如果使用scrollToRowAtIndexPath滚动到单元格而不是滚动视图本身会更好...

[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:row inSection:0] atScrollPosition:UITableViewScrollPositionMiddle animated:YES];

Answer 2

CGFloat animatedDistance;
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 = 215;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 140;

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

    CGRect textFieldRect = [self.view.window convertRect:textField.bounds fromView:textField];
    CGRect viewRect = [self.view.window convertRect:self.view.bounds fromView:self.view];
    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;
    }
    UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];
    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];
    [toolbar setAlpha:1];
    [tbl setContentOffset:CGPointMake(0, [tbl contentOffset].y + 1.35*animatedDistance )];
    [UIView commitAnimations];
}

在UITableView单元格文本字段上滚动视图

2 个答案: