How to set the ToolTip of WPF ComboBox based on selected value?

Question

I have a ComboBox in my WPF application. Using below code I can set the ToolTip as selected value:

ToolTip="{Binding Path=SelectedValue, RelativeSource={RelativeSource Self}}"

But if I need to set a separate value for ToolTip based on ComboBox selection, the following code is not working:

<controls:ComboBoxEx.Style>
    <Style TargetType="ComboBox" BasedOn="{StaticResource basicStyle}">
        <Style.Triggers>
            <DataTrigger Binding="{Binding Path=SelectedValue, RelativeSource={RelativeSource Self}}" Value="DAW">
                <Setter Property="ToolTip" Value="abc"/>
            </DataTrigger>

            <DataTrigger Binding="{Binding Path=SelectedValue, RelativeSource={RelativeSource Self}}" Value="generic">
                <Setter Property="ToolTip" Value="def"/>
            </DataTrigger>
        </Style.Triggers>
    </Style>
</controls:ComboBoxEx.Style>

What is your ComboBox bound to? A list of strings? Out of interest, try using SelectedItem rather than SelectedValue. — Matt Hamilton, Mar 05 '13 at 23:48

score 6 · Accepted Answer · answered Mar 05 '13 at 23:50

6

I'm not sure if I understand correctly, but if you are using a Style you should not have to use a DataTrigger or RelativeSource={RelativeSource Self}}" to access SelectedValue, you should be able to access via a Trigger using the Property

<Style TargetType="ComboBox">
    <Style.Triggers>
        <Trigger Property="SelectedValue"  Value="DAW">
            <Setter Property="ToolTip" Value="abc"/>
        </Trigger>
        <Trigger Property="SelectedValue" Value="generic">
            <Setter Property="ToolTip" Value="def"/>
        </Trigger>
    </Style.Triggers>
</Style>

answered Mar 05 '13 at 23:50

sa_ddam213

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I tried this...but not working... If I put the following setter as default ..it guives me the correct values DAW and generic when ever i select them...but inside the it is not working. – Relativity Mar 05 '13 at 23:57
Do you have `SelectedvaluePath` set on your `ComboBox` – sa_ddam213 Mar 06 '13 at 00:11
What data type is in the combobox, can you post your ComboBox xaml, and a example of your collection. – sa_ddam213 Mar 06 '13 at 00:16
Thanks for your help...I have figured it out ...instead of using data triggger with selected value..i used data trigger with original model object...now it is working fine. Thanks – Relativity Mar 06 '13 at 16:29

score 2 · Answer 2 · edited Mar 28 '18 at 14:35

2

Bind the tooltip to the display property of the selected item in this case i have property name display, if you have declarative ComboBox items then that would be

ToolTip="{Binding Path=SelectedItem.Content,ElementName=cmbbox_years}"

Else for custom object below code will work

<ComboBox 
  Name="cmbbox_years" 
  DisplayMemberPath="display" 
  SelectedValuePath="value"
  ItemsSource="{Binding Years}" 
  SelectedItem="{Binding YearSelectedItem}" 
  ToolTip="{Binding Path=SelectedItem.display,ElementName=cmbbox_years}"/>

edited Mar 28 '18 at 14:35

wonea

4,783
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answered Mar 06 '13 at 06:32

Syed Waqas

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This will work for a single pass, but it won't update the ToolTip with subsequent viewmodel changes. See https://stackoverflow.com/a/7313801/271200 – wonea Mar 28 '18 at 14:38

How to set the ToolTip of WPF ComboBox based on selected value?

2 Answers2