How do I bind a textblock text to a combobox (shown below) selected item? I just need to know the correct binding expression.

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I have a ComboxBox, whose XAML is below. I need to bind textblocks that are elsewhere on the form to the textblocks in the ComboBox selected item. How do I do that?

HTML

<combobox x:name="VictimNames" margin="0,5,0,0" height="30" fontweight="Bold" width="600" 
="" itemssource="{Binding Form104CModel.Incident.Victims}" isreadonly="True" iseditable="False" selecteditem="">
    <combobox.itemtemplate>
        <datatemplate>
            <grid>
                <grid.rowdefinitions>
                    <rowdefinition>
                
                <grid.columndefinitions>
                    <columndefinition width="100">
                    <columndefinition width="100">
                    <columndefinition width="90">
                    <columndefinition width="100">
                    <columndefinition width="100">
                    <columndefinition width="100">
                
                <textblock grid.row="0" grid.column="0" x:name="VictimLastName" text="{Binding LastName}">
                <textblock grid.row="0" grid.column="1" x:name="VictimFirstName" text="{Binding FirstName}">
                <textblock grid.row="0" grid.column="2" x:name="VictimMiddleName" text="{Binding MiddleName}">
                <textblock grid.row="0" grid.column="3" x:name="VictimRace" text="{Binding Race}">
                <textblock grid.row="0" grid.column="4" x:name="VictimGender" text="{Binding Gender}">
                <textblock grid.row="0" grid.column="5" x:name="VictimDOB">
                    <textblock.text>
                        <binding path="DOB">
                            <binding.converter>
                                <infraconverters:dateconverter>
                                           </Binding.Converter>
                                        </Binding>
                                    </TextBlock.Text>   
                                    </TextBlock>
                                </Grid>
                            </DataTemplate>
                        </ComboBox.ItemTemplate>
                    </ComboBox>

What I have tried:

I have tried

HTML

Text="{Binding VictimNames.SelectedItem.<field>}"

for each TextBlock, replacing <field> with the ComboBox Template TextBox x:Name, but that didn't work.

Posted 29-Mar-19 7:16am

Member 12061698

Updated 29-Mar-19 11:23am

v3

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Comments

Member 12061698 29-Mar-19 13:52pm

I asked for an answer to a problem, not an editorial opinion. If that's the best you can do, you're not helpful at all. And you're supposed to be a top expert? That kind of 'expert' help is the kind I don't need.

3 solutions

Solution 1

That's what happens when you chuck code-behind: confusion and delays.

You should bind the selected item (object) to a proper "type"; then bind that instance to the text boxes; with defaults if the Selected Index is -1 (i.e. "nothing" selected).

(Yes; I give opinions too).

Posted 29-Mar-19 7:53am

Gerry Schmitz

Updated 29-Mar-19 7:54am

v2

Solution 2

if I understand this correctly, when the user selects an item from the ComboBox, the selected item is used to populate an object which is bound to the TextBlocks.

How about this:
Use the select index of the ComboBox to bind the TextBlocks to the underlying data of the ComboBox.

Posted 29-Mar-19 8:26am

Member 12061698

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Member 12061698 · Accepted Answer · 2019-03-29T11:24:00

I found the answer.  It was as simple as I first thought.  The ComboBox was to be populated with victim data when the user selected a victim.  

I figured it had to be a simple binding to the selected item, and it is.  Here is how it is done for the InvolvementNumber, which is a victim property. VictimNames is the ComboBox, and the Path got me there. 

 <StackPanel Grid.Row="0" Grid.Column="0">
     <TextBlock> #</TextBlock>
     <TextBlock Name="VictimNumber"  
         Style="{StaticResource PartIIGridIsEnabledTextBlock}" 
         Text="{Binding ElementName=VictimNames,Path=SelectedItem.InvolvementNumber}"/> </StackPanel>

One more thing: The Path must go to the property of the underlying data, not the name of the object in the ComboBox.ItemTemplate.