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wpfbindingtooltip

BindingExpression path error at ToolTip binding

I used ToolTip in DataGridCell. In my project, I used AvalonDock and I created 3 or 4 Window tabs. And then, it works well and also tooltips displayed well in DataGrid, but there are errors when i swapped tabs. I think load procedure...
Here is a part of my .xaml code.

        <DataGrid.CellStyle>
            <Style TargetType="DataGridCell" BasedOn="{StaticResource MetroDataGridCell}">
                    <Setter Property="ToolTip" Value="{Binding Path=Content.Text, RelativeSource={RelativeSource Self}}" />
            </Style>
        </DataGrid.CellStyle>

It worked. But there are errors that say

System.Windows.Data Error: 40 : BindingExpression path error: 'Text' property not found on 'object' ''ContentPresenter' (Name='')'. BindingExpression:Path=Content.Text; DataItem='DataGridCell' (Name=''); target element is 'DataGridCell' (Name=''); target property is 'ToolTip' (type 'Object')

How can I fix it?

+ Addition I modified the source.

<Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=Content}" />

enter image description here

Then, BindingExpression errors were dissapeared. But contents of DataGridCell is dissapear after showing ToolTip like picture I posted!! Strange Bug !!!

Solution

  • I make my ToolTip in this way:

    <Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=Content.Text}"/>

    Alternativ

    <DataGrid>
    <DataGrid.Columns>
        <DataGridTemplateColumn>
            <DataGridTemplateColumn.Header>
                <TextBlock Text="Foo Header"/>
            </DataGridTemplateColumn.Header>
            <DataGridTemplateColumn.CellTemplate>
                <DataTemplate>
                    <DataTemplate.Resources>
                        <Style TargetType="{x:Type TextBlock}">
                            <Setter Property="ToolTip">
                                <Setter.Value>
                                    <ToolTip 
                                            Style="{StaticResource ToolTipBrowserDescription}" 
                                            Content="{Binding FooProperty}"
                                            HasDropShadow="True">
                                    </ToolTip>
                                </Setter.Value>
                            </Setter>
                        </Style>
                    </DataTemplate.Resources>
                    <TextBlock Text="{Binding FooProperty}" TextTrimming="CharacterEllipsis"/>
                </DataTemplate>
            </DataGridTemplateColumn.CellTemplate>
        </DataGridTemplateColumn>
    </DataGrid.Columns>
</DataGrid>

    ToolTipStyle

    <Style TargetType="{x:Type ToolTip}" x:Key="ToolTipBrowserDescription">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ToolTip}">
                <Border BorderBrush="#FF424242" Background="#FFEEEEEE" BorderThickness="1">
                    <TextBlock Text="{TemplateBinding Content}" FontWeight="Bold" TextWrapping="Wrap" Margin="5" MinWidth="50" MaxWidth="500"/>
                    <Border.Effect>
                        <DropShadowEffect Opacity="0.65" ShadowDepth="1"/>
                    </Border.Effect>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="ToolTipService.HasDropShadow" Value="True">
                        <Setter Property="Margin" Value="0,0,1,1"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

    Preview

    preview