使用GridView获取ListView标题的高度 [英] Get height of header of a ListView with GridView
问题描述
如何通过 GridView 获取 ListView 的标题高度？它甚至有可能吗？
我需要根据 ListView 所以我开始写一个 Converter 。问题是我无法访问实际高度。
Visual Studio的调试器显示 HeaderRowPresenter 的属性，该属性又具有属性 ActualHeight 。但我无法访问它， HeaderRowPresenter 似乎是受保护或私有的。
所有其他 ColumnHeader * 属性（ ColumnHeaderContainerStyle ， ColumnHeaderTemplate 等）都是 对于所有 Header * 属性在 Columns （除了作为标题内容的 String ）。
顺便说一句：我试图解决一个不同的问题和我目前的方法让我这样做，所以也许我采取了错误的方式。
好的，我找到了解决方案，但我不是很自豪，因为它使用反射：
我写了 Converter 一个 View 和一个 ListView 作为值和参数，并返回高度t
public class HeightSyncConverter：IValueConverter
{
public object Convert（object value ，类型targetType，对象参数，CultureInfo culture）
{
GridView gvLocal = value作为GridView;
ListView lvOther =参数为ListView;
if（gvLocal == null || lvOther == null）
{
return 0;
}
GridView gvOther =（GridView）lvOther.View;
try
{
//获取非公共HeaderRowPresenter属性
GridViewHeaderRowPresenter hrpLocal =（GridViewHeaderRowPresenter）gvLocal.GetType（）。GetProperty（HeaderRowPresenter，BindingFlags.NonPublic | BindingFlags .Instance）.GetValue（gvLocal）;
GridViewHeaderRowPresenter hrpOther =（GridViewHeaderRowPresenter）gvOther.GetType（）。GetProperty（HeaderRowPresenter，BindingFlags.NonPublic | BindingFlags.Instance）.GetValue（gvOther）;
if（hrpLocal == null || hrpOther == null）
{
return 0;
}
//只有在其他ListView的标题高于本地
的情况下才有效if（hrpLocal.ActualHeight> hrpOther.ActualHeight）
{
返回0;
}
return hrpOther.ActualHeight - hrpLocal.ActualHeight;
}
catch（TargetInvocationException）{}
return 0;
公共对象ConvertBack（对象值，类型targetType，对象参数，CultureInfo culture）
{
return null;
}
}
然后我用它来定义 Grid.Row ：
< UserControl x：Class =GUI。 ListViewLayout
xmlns =http://schemas.microsoft.com/winfx/2006/xaml/presentation
xmlns：x =http://schemas.microsoft.com/winfx/2006/ xaml
xmlns：mc =http://schemas.openxmlformats.org/markup-compatibility/2006
xmlns：d =http://schemas.microsoft.com/expression/blend/ 2008
xmlns：local =clr-namespace：GUI
xmlns：conv =clr-namespace：GUI.Converter
mc：Ignorable =dd：DesignHeight = 300d：DesignWidth =300
Loaded =Window_Loaded>
< UserControl.Resources>
< Style x：Key =verticalGridViewColumnHeaderTargetType =GridViewColumnHeader>
< Setter Property =ContentTemplate>
< Setter.Value>
< DataTemplate>
< TextBlock Text ={Binding}FontWeight =Bold
VerticalAlignment =CenterTextAlignment =CenterHorizontalAlignment =Center>
< TextBlock.LayoutTransform>
< RotateTransform Angle =270/>
< /TextBlock.LayoutTransform>
< / TextBlock>
< / DataTemplate>
< / Setter>
< / style>
< conv：HeightSyncConverter x：Key =myConverter/>
< /UserControl.Resources>
< Grid x：Name =grid>
< Grid.ColumnDefinitions>
< ColumnDefinition Width =150/>
< ColumnDefinition Width =150/>
< /Grid.ColumnDefinitions>
< Grid.RowDefinitions>
< RowDefinition Height =Auto/>
< RowDefinition x：Name =fillerRowHeight ={Binding View，ElementName = listView1，Converter = {StaticResource myConverter}，ConverterParameter = {x：Reference listView2}}/>
< RowDefinition Height =*/>
< /Grid.RowDefinitions>
< Button x：Name =someControlGrid.RowSpan =2>占位符< / Button>
< ListView x：Name =listView1Grid.Row =2>
< ListView.View>
< GridView>
< GridViewColumn Header =Header 1Width =60/>
< GridViewColumn Header =Header 2Width =60/>
< / GridView>
< /ListView.View>
< / ListView>
< ListView x：Name =listView2Grid.Row =1Grid.Column =1Grid.RowSpan =2>
< ListView.View>
< GridView>
< GridViewColumn Header =Long Header 1
HeaderContainerStyle ={StaticResource verticalGridViewColumnHeader}Width =Auto/>
< GridViewColumn Header =Long Header 2
HeaderContainerStyle ={StaticResource verticalGridViewColumnHeader}Width =Auto/>
< / GridView>
< /ListView.View>
< / ListView>
< / Grid>
< / UserControl>
问题是转换器在 ListView s和它们的头文件被初始化了，所以我重新评估了代码隐藏中的 Binding ：
<$ p $用户控件
{
public ListViewLayout（）
{
InitializeComponent（）;
private void Window_Loaded（object sender，RoutedEventArgs e）
{
BindingExpression binding = fillerRow.GetBindingExpression（RowDefinition.HeightProperty）;
binding.UpdateTarget（）;
}
}
总而言之，我不认为这是值得付出努力，最好的方法是自己定义标题的高度，而不是检索自动计算的 ActualHeight 。
How can I get the height of the header of a ListView with a GridView? Is it even possible?
I need to set the height of one control based on the height of the header of a ListView so I started writing a Converter. The problem is that I can't access the actual height.
The debugger of Visual Studio shows me that GridView has a property called HeaderRowPresenter, which in turn has a property ActualHeight. But I can't access it, HeaderRowPresenter seems to be protected or private.
All other ColumnHeader* properties (ColumnHeaderContainerStyle, ColumnHeaderTemplate, etc.) are null on this object, same for all Header* properties on the Columns (except for the String that is the content of the header).
Btw: I'm trying to solve a different problem and my current approach let me to this, so maybe I'm taking this on the wrong way.
Okay, I've found a solution but I'm not very proud of it, because it uses reflection:
I wrote a Converter that takes a View and a ListView as value and parameter and returns the height difference of the headers:
public class HeightSyncConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
GridView gvLocal = value as GridView;
ListView lvOther = parameter as ListView;
if( gvLocal == null || lvOther == null)
{
return 0;
}
GridView gvOther = (GridView)lvOther.View;
try
{
// get the non-public HeaderRowPresenter property
GridViewHeaderRowPresenter hrpLocal = (GridViewHeaderRowPresenter)gvLocal.GetType().GetProperty("HeaderRowPresenter", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(gvLocal);
GridViewHeaderRowPresenter hrpOther = (GridViewHeaderRowPresenter)gvOther.GetType().GetProperty("HeaderRowPresenter", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(gvOther);
if( hrpLocal == null || hrpOther == null )
{
return 0;
}
// Only works if the other ListView's header is higher than the local one's
if( hrpLocal.ActualHeight > hrpOther.ActualHeight )
{
return 0;
}
return hrpOther.ActualHeight - hrpLocal.ActualHeight;
}
catch(TargetInvocationException) { }
return 0;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return null;
}
}
I then use it to define the height of a Grid.Row:
<UserControl x:Class="GUI.ListViewLayout"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:GUI"
xmlns:conv="clr-namespace:GUI.Converter"
mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"
Loaded="Window_Loaded">
<UserControl.Resources>
<Style x:Key="verticalGridViewColumnHeader" TargetType="GridViewColumnHeader">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock Text="{Binding}" FontWeight="Bold"
VerticalAlignment="Center" TextAlignment="Center" HorizontalAlignment="Center">
<TextBlock.LayoutTransform>
<RotateTransform Angle="270" />
</TextBlock.LayoutTransform>
</TextBlock>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
<conv:HeightSyncConverter x:Key="myConverter" />
</UserControl.Resources>
<Grid x:Name="grid">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="150" />
<ColumnDefinition Width="150" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition x:Name="fillerRow" Height="{Binding View, ElementName=listView1, Converter={StaticResource myConverter}, ConverterParameter={x:Reference listView2}}" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Button x:Name="someControl" Grid.RowSpan="2">Placeholder</Button>
<ListView x:Name="listView1" Grid.Row="2">
<ListView.View>
<GridView>
<GridViewColumn Header="Header 1" Width="60"/>
<GridViewColumn Header="Header 2" Width="60" />
</GridView>
</ListView.View>
</ListView>
<ListView x:Name="listView2" Grid.Row="1" Grid.Column="1" Grid.RowSpan="2">
<ListView.View>
<GridView>
<GridViewColumn Header="Long Header 1"
HeaderContainerStyle="{StaticResource verticalGridViewColumnHeader}" Width="Auto" />
<GridViewColumn Header="Long Header 2"
HeaderContainerStyle="{StaticResource verticalGridViewColumnHeader}" Width="Auto" />
</GridView>
</ListView.View>
</ListView>
</Grid>
</UserControl>
The problem is that the converter is called before the ListViews and their headers are initialized, so I reevaluate the Binding in the code-behind:
public partial class ListViewLayout : UserControl
{
public ListViewLayout()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
BindingExpression binding = fillerRow.GetBindingExpression(RowDefinition.HeightProperty);
binding.UpdateTarget();
}
}
All in all, I don't think this is worth the effort and the best way is to define the height of the headers myself instead of retrieving an automatically calculated ActualHeight.
这篇关于使用GridView获取ListView标题的高度的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
