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Binding WPF Combobox using EntityCollection by adnan8t2

adnan8t2 — Mon, 06 Sep 2010 10:33:24 GMT

Modifying my last message.

Solved.

Added DataContext="{Binding}" in Combobox XAML.
Plus First letter of the Field is in caps "strDisplayAs" (As Walaa said)

Old XAML

Code:


<ComboBox Grid.Column="1" Grid.Row="0" VerticalAlignment="Bottom"
             Margin="10,0,10,0" Name="cmbHospital"
             IsSynchronizedWithCurrentItem="True"
             ItemsSource="{Binding}"
             ItemTemplate="{StaticResource HospitalListTemplate}"
             />

New XAML

Code:


<ComboBox Grid.Column="1" Grid.Row="0" VerticalAlignment="Bottom"
             Margin="10,0,10,0" Name="cmbHospital"
             IsSynchronizedWithCurrentItem="True" 
             ItemsSource="{Binding}"
             DataContext="{Binding}"
             ItemTemplate="{StaticResource HospitalListTemplate}" />

Binding WPF Combobox using EntityCollection by adnan8t2

adnan8t2 — Mon, 06 Sep 2010 10:07:16 GMT

Just added DataContext="{Binding}" in Combobox XAML and problem solved.

Old XAML

Code:


            <ComboBox Grid.Column="1" Grid.Row="0" VerticalAlignment="Bottom"
             Margin="10,0,10,0" Name="cmbHospital"
             IsSynchronizedWithCurrentItem="True"
             ItemsSource="{Binding}"
             ItemTemplate="{StaticResource HospitalListTemplate}"
             />

Old XAML

Code:


            <ComboBox Grid.Column="1" Grid.Row="0"  VerticalAlignment="Bottom"
             Margin="10,0,10,0" Name="cmbHospital"
             IsSynchronizedWithCurrentItem="True" 
             ItemsSource="{Binding}"
             DataContext="{Binding}"
             ItemTemplate="{StaticResource HospitalListTemplate}" />

Thanks David & Thanks Walaa for your consideration on my problem.

Regards,
Adnan

Binding WPF Combobox using EntityCollection by Walaa

Walaa — Mon, 06 Sep 2010 08:24:43 GMT

Just for trial, remove the ItemTemplate and use DisplayMemberPath.

Also please check the Field's casing "strDisplayAs", shouldn't the first letter be in capital letter.

Binding WPF Combobox using EntityCollection by adnan8t2

adnan8t2 — Mon, 06 Sep 2010 06:54:27 GMT

Dear David,

Thanks for your consideration but the major and only difference between hospital combo and department combo is the datacontext,

in hospital

Code:


cmbHospital.DataContext = objDBRelated.GetHospital() [b]'Retrun EntityCollection[/b]

in department

Code:


objSPCalling.GetHospitalDepartment(p_nHospitalId) [b]'Return Datatable[/b]

and when i change cmbHospital.DataContext to DataTable it is working fine

Thanks & Regards,
Adnan

Binding WPF Combobox using EntityCollection by daelmo

daelmo — Mon, 06 Sep 2010 02:32:23 GMT

Basically both department and hospital comboboxes are setup similar. I would check whether you have casing mismatches in field names or something like that.

Binding WPF Combobox using EntityCollection by adnan8t2

adnan8t2 — Sun, 05 Sep 2010 08:05:30 GMT

Dear All,

I am having a blank combobox when doing this,

'Code to fill Hospital Combobox (cmbHospital)

Code:


    Private Sub FillHospital()
        Dim objDBRelated As New DBRelated
        cmbHospital.DataContext = objDBRelated.GetHospital() 'Retrun EntityCollection

        AddHandler cmbHospital.SelectionChanged, AddressOf 
        cmbHospital_OnSelectionChanged
    End Sub

I am calling this function on MyBase.Loaded

'Hospital Combobox XAMAL

Code:

'XAML
            <ComboBox Grid.Column="1" Grid.Row="0"  VerticalAlignment="Bottom"
             Margin="10,0,10,0" Name="cmbHospital"
             IsSynchronizedWithCurrentItem="True" ItemsSource="{Binding}"
             ItemTemplate="{StaticResource HospitalListTemplate}"
             />

'HospitalListTemplate is defined as

Code:

         <DataTemplate x:Key="HospitalListTemplate">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding Path=strDisplayAs}" Margin="0,0,2,0" 
                 VerticalAlignment="Center"/>
                <TextBlock VerticalAlignment="Center">
                    <Bold><Label Content="{Binding Path=intNoOfBeds}" /></Bold>
                </TextBlock>
                <Image Margin="11,0,0,0" Source="../Images/edit-48.png" 
                 VerticalAlignment="Center" Width="28" Height="28" 
                 RenderOptions.BitmapScalingMode="HighQuality"/>
            </StackPanel>
        </DataTemplate>

when i execute above i am having 19 blank items in my combo, as i've 19 hospitals in my db table, not only this even the cmbHospital_OnSelectionChanged is working fine whenever i made another selection from combobox (i am filling departments on selected hospital).

Code:

    Sub cmbHospital_OnSelectionChanged(ByVal sender As Object, ByVal e As RoutedEventArgs)
            FillDepartment(CType(CType(cmbHospital.SelectedItem, 
            HospitalEntity).Fields("HospitalId").DbValue, Integer))
    End Sub

On other hand I am using datatable as the datacontext for Department combobox and which is working fine (displaying departments).

'Code to fill Department Combobox (cmbDepartment)

Code:


    Private Sub FillDepartment(ByVal p_nHospitalId As Integer)
        Dim objSPCalling As New SPCalling
        cmbDepartment.DataContext = 
        objSPCalling.GetHospitalDepartment(p_nHospitalId) 'Return Datatable
    End Sub

'Department Combobox XAMAL

Code:

            <ComboBox Grid.Column="1" Grid.Row="1"  VerticalAlignment="Bottom"
              Margin="10,0,10,0" Name="cmbDepartment" 
              IsSynchronizedWithCurrentItem="True" 
              ItemsSource="{Binding}"
              ItemTemplate="{StaticResource DepartmentListTemplate}"
              />

'Department ListTemplate is defined as

Code:

         <DataTemplate x:Key="HospitalListTemplate">
            <StackPanel Orientation="Horizontal">
                <TextBlock Text="{Binding Path=strDisplayAs}" Margin="0,0,2,0" 
                 VerticalAlignment="Center"/>
                <TextBlock VerticalAlignment="Center">
                    <Bold><Label Content="{Binding Path=intSort}" /></Bold>
                </TextBlock>
                <Image Margin="11,0,0,0" Source="../Images/edit-48.png" 
                 VerticalAlignment="Center" Width="28" Height="28" 
                 RenderOptions.BitmapScalingMode="HighQuality"/>
            </StackPanel>
        </DataTemplate>

Any idea why these hospital items are not getting displayed.

Note: I am using image in both Datatemplates as for my practice.

Regards,

Loading LLBLDataSource before Page_Load in ASP.NET by Walaa

Walaa — Thu, 02 Sep 2010 07:42:57 GMT

I would have used a FormView to edit the Employee info, and thus it should be bound to the Employee entity, and then the Departement DropDownList should have its SelectedValue bound to the Employee's DepartementId.

But if you want to do it your way, then try the Page_PreRender event, or the DropDownList dataBound event.

Loading LLBLDataSource before Page_Load in ASP.NET by amitjindal

amitjindal — Thu, 02 Sep 2010 07:18:53 GMT

Hello,

We are running into a sort of problem. Let's say for example, we have a page with various controls including some combo boxes like Employee page with department and manager combo boxes.

We have bound the combo boxes via LLBL Data Source. When we come to page for editing an employee, on Page_Load event we try to fill the values in all controls from existing values including selecting existing department and manager. But on page_load the combo boxes are not yet filled.

The combo boxes are DevExpress ASP.net combo boxes.

So is it by design or is there a better way to do this?

Thanks
Amit

FieldCompareRangePredicate + NOT IN by jmcjq2

jmcjq2 — Thu, 02 Sep 2010 00:36:48 GMT

Walaa wrote:

The FieldCompareRangePredicate Ctor has an overload that accepts a boolean negate parameter, please set that to true.

Got it! Thanks
John

FieldCompareRangePredicate + NOT IN by Walaa

Walaa — Wed, 01 Sep 2010 08:36:46 GMT

The FieldCompareRangePredicate Ctor has an overload that accepts a boolean negate parameter, please set that to true.