WPF组合框内滚动查看器不工作
问题描述:
我有一个telerik Combobox的问题,它也可以复制为基本的WPF组合框。WPF组合框内滚动查看器不工作
我有以下情况:当用户试图打开组合框时,整个页面(包括此控件)应该向上移动,因为在底部部分空间将被键盘占用。
为了做到这一点,我抓住了GotFocus事件,我已经以编程方式更新了滚动查看器的位置。
这里是XAML:
<ScrollViewer Grid.Row="2" x:Name="KeyBoardScrollViewer" PanningMode="VerticalOnly" VerticalScrollBarVisibility="Hidden">
<telerik:RadComboBox Grid.Row="5" GotFocus="UIElement_OnGotFocus" LostFocus="UIElement_OnLostFocus"
IsEditable="True"
Grid.Column="1"
ItemsSource="{Binding StreetOthers, Mode=TwoWay}"
Text="{Binding SelectedStreetOthers, Mode=TwoWay, ValidatesOnDataErrors=True, UpdateSourceTrigger=PropertyChanged}"
Height="36" Width="250"
HorizontalAlignment="Left"
VerticalAlignment="Top"
FontSize="18"
Margin="10 0 0 0"
Padding="5" />
</ScrollViewer>
而后面的代码:
public double RememberedPoisitionOfScrollBar { get; set; }
private void UIElement_OnGotFocus(object sender, RoutedEventArgs e)
{
Application.Current.Dispatcher.InvokeAsync(() =>
{
if (!Keyboard.IsOpen)
{
Keyboard.IsOpen = true;
KeyBoardScrollViewer.VerticalScrollBarVisibility = ScrollBarVisibility.Visible;
}
Point relativePoint = ((FrameworkElement)sender).TransformToAncestor(KeyBoardScrollViewer)
.Transform(new Point(0, 0));
KeyBoardScrollViewer.CanContentScroll = false;
RememberedPoisitionOfScrollBar = relativePoint.Y - 5;
var offset = KeyBoardScrollViewer.VerticalOffset + relativePoint.Y - 5; //sender.OccludedRect.Top
KeyBoardScrollViewer.ScrollToVerticalOffset(offset);
//KeyBoardScrollViewer.ScrollToVerticalOffset(offset);
KeyBoardScrollViewer.UpdateLayout();
});
Keyboard.Width = this.ActualWidth;
}
private void UIElement_OnLostFocus(object sender, RoutedEventArgs e)
{
Keyboard.IsOpen = false;
KeyBoardScrollViewer.ScrollToVerticalOffset(KeyBoardScrollViewer.VerticalOffset - RememberedPoisitionOfScrollBar);
KeyBoardScrollViewer.UpdateLayout();
KeyBoardScrollViewer.VerticalScrollBarVisibility = ScrollBarVisibility.Hidden;
}
此解决方案,组合框移动到视图的顶部,但我有一个奇怪的行为。组合框“内容”保留在原始位置,并且不会根据组合框的新位置进行更新。 这里是图片:
根据Telerik的管理员(old post)这是一个WPF的问题,但它是一个解决办法,不是吗?任何想法都很有用!
谢谢!
答
在滚动浏览,订阅ScrollChanged事件:
ScrollChanged="KeyboardScrollView_OnScrollChanged"
,并在代码隐藏,如果下拉列表处于打开状态时滚动出现,将其关闭并重新打开:
private void KeyboardScrollView_OnScrollChanged(object sender, ScrollChangedEventArgs e)
{
if (TheComboBox.IsDropDownOpen)
{
TheComboBox.IsDropDownOpen = false;
TheComboBox.IsDropDownOpen = true;
}
}