Combo box default value

Question

I want to use combo box and the following code is working but now I want to add to the combo box header default value ,i.e. there is value and like Item and when you open it you have the option to change it,how I can do that?

<ComboBox  ItemsSource="{Binding Items}" SelectedValue="{Binding SelectedItem}"  
 Name="comboBox1" Text="Item" Grid.Column="3" Grid.Row="2" />

the code

private List<String> _items;
private String _selectedItem;
private String _selectedBusinessItem;
public List<String> Items
{
    get { return _items; }
    set
    {
        _items = value;
        OnPropertyChanged("Items");
    }
}

public String SelectedItem1
{
    get { return _selectedItem; }
    set
    {
        _selectedItem = value;
        OnPropertyChanged("Items");
    }
}

private void InitCombo()
{
    Items = new List<string> { "item",  "Item2", "Item3" };
    SelectedItem1 = Items[0];
}

@Sheridan- I.e. you dont need to open the combo box to see the first value,The first value is on the combo box and when you open it you see the others... — John Jerrby, Jan 30 '14 at 15:09
I don't see a OnPropertyChanged("SelectedItem1"); And the binding is to SelectedItem (not SelectedItem1). — paparazzo, Jan 30 '14 at 15:20
Try `SelectedIndex="0"` for `ComboBox` and in SelectedValue must `SelectedValue="{Binding SelectedItem1}"`. — Anatoliy Nikolaev, Jan 30 '14 at 15:21

score 3 · Answer 1 · answered Jan 30 '14 at 15:28

It's hard to understand you are asking, but I think you are just looking for the ComboBox to show the first value in the collection of Items.

I believe you can do this a few ways.

First you need to fix SelectedValue binding to match your property name, and drop the Text="Item":

<ComboBox  ItemsSource="{Binding Items}" SelectedValue="{Binding SelectedItem1}"  
           Name="comboBox1" Grid.Column="3" Grid.Row="2" />

From your code you can set the SelectedValue1 property that you have to any of the string items. Examples of this:

SelectedValue1 = "item";

-or-

SelectedValue1 = Items.FirstOrDefault();

I used FirstOrDefault as a safety incase these items didn't exist.

-or-

SelectedValue1 = Items[0];

And there are several more options here. But I'm going to try and limit the scope of the answer.

Also, you should be able to set the ComboBox.SelectedIndex to 0.

<ComboBox  ItemsSource="{Binding Items}" SelectedValue="{Binding SelectedItem1}"  
           Name="comboBox1" Grid.Column="3" Grid.Row="2"
           SelectedIndex="0"/>

score 1 · Accepted Answer · edited May 23 '17 at 11:51

I think that you're talking about the ComboBox.Text Property... from the linked page:

Gets or sets the text of the currently selected item

This is not a free field that you can display a message in. It displays the value of the currently selected item from the ComboBox.Items collection. If the text is not in one of the items, then this TextBox 'should' not display that value.

However, there are always workarounds. The correct way to do it would be to define a new ControlTemplate for the ComboBox that contains a TextBlock that is overlayed on top of the selected item TextBox and hidden when required.

Some people think that that is too much work though and so you can find a number of alternative solutions in the How to display default text “--Select Team --” in combo box on pageload in WPF? post here on StackOverflow.

Beware because that *might* enable users to add your default message into the collection as an item... maybe by pressing Enter. — Sheridan, Jan 30 '14 at 15:37

score 0 · Answer 3 · answered Dec 31 '15 at 03:08

List Items = new List { "item", "Item 2", "Item 3" };
Set the Selected Index = 0, It will select the first element in the combo box Item-source

XAML:

<ComboBox  ItemsSource="{Binding Items}"  
           Name="comboBox1" Grid.Column="3" Grid.Row="2"
           SelectedIndex="0"/>

Combo box default value

3 Answers3

XAML: