Programming with .NET - General

Re: Re: Re: Re: How to set SelectedItem in combobox?

reinux — Sun, 03 May 2009 18:20:27 GMT

I've reported this issue as a bug. If it's the same problem that I'm having, the problem is that ItemCollection.IndexOf, which SelectedItem calls, doesn't work with value types.

Re: Re: Re: Re: How to set SelectedItem in combobox?

SteveReconG — Tue, 17 Mar 2009 15:28:49 GMT

This is rather absurb that I must use selectedindex vs. selecteditem

ie. I don't code in the code behind , I'm using MVVM

I have bound selectedItem with Two-Way mode, it should pick this up

SelectedItem="{Binding myItem, Mode=TwoWay}"

Re: Re: Re: How to set SelectedItem in combobox?

silverstarter — Tue, 23 Dec 2008 12:39:12 GMT

did u check if theres useful stuff in the result ?

ever checked if it works if u type in exactly a value which is part of the slcmbArea?

slcmbArea.SelectedItem = "aexistingitem";

realy weird cause in my app the stuff is working

Re: Re: Re: How to set SelectedItem in combobox?

lijoputhuval — Tue, 23 Dec 2008 09:10:05 GMT

here am posting the code.

i have both id and value of the combobox item in the string.

here the selectionboxitem is giving error.

void AreaServiceSoapClient_GetCompleted(object sender, MyProject.Silverlight.AreaService.GetCompletedEventArgs e)

{

if (e.Error == null)

{

AreaService.ArrayOfString sResult = e.Result

slcmbFunctionalArea.UpdateLayout();

//slcmbArea.SelectedIndex= sResult[1];

//slcmbArea.SelectionBoxItem = sResult[2];

slcmbArea.SelectedItem = sResult[2];

}

Re: Re: How to set SelectedItem in combobox?

silverstarter — Tue, 23 Dec 2008 07:29:53 GMT

oh sorry, i have used both ways for little different applications

MyBox.SelectedItem = MyBox2.SelectedItem;

works fine for me

may use

MyBox.updatelayout() infront of the selection or check if it works when u choose a integer instead of the string with .selectedindex= ...

if all this doesnt work then may paste the codesnippet here

Re: Re: How to set SelectedItem in combobox?

lijoputhuval — Tue, 23 Dec 2008 05:16:19 GMT

hi silverstarter ,

i have tried the above code.

but its give me a error.

Property or indexer 'System.Windows.Controls.ComboBox.Selection Box Item' cannot be assigned to -- it is read only

Re: How to set SelectedItem in combobox?

silverstarter — Mon, 22 Dec 2008 13:24:24 GMT

display it with

mycombo.SelectionBoxItem="item1"

Re: How to set SelectedItem in combobox?

lijoputhuval — Mon, 22 Dec 2008 06:59:01 GMT

i have a similar problem.

i had already bind the combobox. i want to set the selected item. after clicking a button

but its not working.!!! :-(

i had set mycombo.SelectedItem="item1";

as the combobox have that item.but it doesnot displays that.

and the selected item is null.

can anybody help!!!!!!!!!..

Re: How to set SelectedItem in combobox?

hoangtuit — Mon, 24 Nov 2008 03:38:23 GMT

Thanks All,

I got it.

Re: How to set SelectedItem in combobox?

manish.dalal — Sun, 23 Nov 2008 14:35:01 GMT

Hi Hoangtuit,

In edit button clik, you will get reference to datagrid item(Resource). Once you have that, you will either need to new up ResourceType based on information from Resouce or use LINQ to find ResourceType form ResourceTypeList that is bound to ComboBox and then set SelectedItem on ComboBox.

I have two blog post on ComboBox where I use similar techniques to find items in ComboBox

http://weblogs.asp.net/manishdalal/archive/2008/09/28/combobox-in-datagrid.aspx

http://weblogs.asp.net/manishdalal/archive/2008/10/22/cascading-combobox.aspx

Re: How to set SelectedItem in combobox?

Jonathan Shen – MSFT — Sun, 23 Nov 2008 12:43:54 GMT

Hi Hoangtuit,

We not are quite sure what is your real problem based on your description. To change the SelectedItem, please reference to shamrat231's reply. However, I guess you have difficulty on how to get the target item when click on the DataGrid. Below is a sample.

<data:DataGrid x:Name="myDataGrid" AutoGenerateColumns="False" Width="500" ItemsSource="{Binding}" RowHeight="40" MouseMove="myDataGrid_MouseMove" SelectionChanged="myDataGrid_SelectionChanged" >
                <data:DataGrid.Columns>
                    <data:DataGridTextColumn Header="First Name" Binding="{Binding FirstName}" Width="300"></data:DataGridTextColumn>

                    <data:DataGridTextColumn Binding="{Binding LastName}" Header="tommy" Width="300">
                        <data:DataGridTextColumn.HeaderStyle>
                            <Style TargetType="dataprimitives:DataGridColumnHeader">
                                <Setter Property="ContentTemplate">
                                    <Setter.Value>
                                        <DataTemplate>
                                            <Button Content="{Binding}" Click="Button_Click" />
                                        </DataTemplate>
                                    </Setter.Value>
                                </Setter>
                            </Style>
                        </data:DataGridTextColumn.HeaderStyle>
                    </data:DataGridTextColumn>
                    <data:DataGridCheckBoxColumn Header="Male" Binding="{Binding Male}" ></data:DataGridCheckBoxColumn>
                    <data:DataGridTextColumn Header="Age" Binding="{Binding Age}" Width="50" ></data:DataGridTextColumn>
                    <data:DataGridTextColumn Header="Age" Binding="{Binding Age}"></data:DataGridTextColumn>
                </data:DataGrid.Columns>
            </data:DataGrid>

private void Button_Click(object sender, RoutedEventArgs e)
        {
            Button curButton = sender as Button;
            Person curPerson = curButton.DataContext as Person;
            //MessageBox.Show(Data.IndexOf(curPerson).ToString());

        }

In other words, we need to get which item is clicked when you choosed. For the usage of DataGrid, please reference to this video tutorials.

GETTING STARTED WITH THE DATAGRID

INSERT, UPDATE, DELETE WITH THE DATAGRID

Please let me know, if my assumption is wrong.

Best regards,

Jonathan

Re: How to set SelectedItem in combobox?

hoangtuit — Wed, 19 Nov 2008 01:45:29 GMT

May be my description is not obvious.

So, I have two list

List<Resource> resourcelist;

List<ResourceType> resourcetypelist;

and two windows.

Window 1: contain a datagrid (Resource List - ItemSource = resourcelist ).

Window 2: contain a textbox (Resource Name) and a combobox (ResourceType - ItemSource = resourcetypelist).

When I choose a item in window 1 and click edit button, Window 2 opened (with parameter is SelectedItem). In window 2, I can bind data to textbox, but I can set SelectedItem in combobox is resource type of item (Item chose in window 1).

Sorry about my bad EN.

Re: Re: How to set SelectedItem in combobox?

Gengis — Tue, 18 Nov 2008 15:00:53 GMT

How about

ItemsSource="{Binding Source={StaticResource dataProvider}, Path=ResourceTypes}}" SelectedItem="{Binding Type}" ??

'Binding Type' assumes the datacontext is an instance of Resource. Of course the binding source may be different.

Re: How to set SelectedItem in combobox?

silverlight_kid — Tue, 18 Nov 2008 11:08:27 GMT

Setting selectedIndex is same way as we doing in c# application

Just add any number of items using

Items.Add("Your Value");

then

yourcombo.selectedIndex=0;

this set index 0 as selected item

Re: How to set SelectedItem in combobox?

shamrat231 — Tue, 18 Nov 2008 04:31:34 GMT

Official way of setting the selected item of combo is using

Combo.SelectedIndex = 0; //set a number,0 indicates the first row.

However, you may want to show something like asp.net selectedItem.Text that you can actually match with your result and set it to true, In silverlight you have to do it in this way,

your class

    public class ResourceType
    {
        public string ID { get; set; }
        public string Name { get; set; }
    }

1. Suppose the combo is populated that means you have added the data in this way

List<ResourceType> list = new List<ResourceType>();
foreach(var n in e.result) {
list.Add( new ResourceType() { ID = n.ID, Name= n.Name});
// [placeholder] something will happen here

}
Combo.ItemSource = list;

So to selcted a particular item like, suppose you want to select the item with name Shamrat, you do it this way

// [placeholder] [add this code there]

if (n.Name == "input") [in this case it has Shamrat]

{Combo.SelectedIndex = Combo.Items.Count -1;}

your item is selected.

and if this post was helpful then please 'Mark as Answer' - many thanks

Sharker Khaleed Mahmud
Software Developer
(MCP,MCTS,MCPD[web])

This credits that member, earns you a point and marks your thread as Resolved so we will all know you have been helped.