Question

I have been playing around and looking around on how to Bind a modelview to a view, but i cant seem to work it out.
I have a view called Search and I want to bind it to SearchModelView.
View has one button and one textbox and looks:

<Grid HorizontalAlignment="Stretch" VerticalAlignment="Stretch" >

    <ComboBox Height="23" HorizontalAlignment="Left" Margin="12,40,0,0" Name="comboBox1" VerticalAlignment="Top" Width="174" />
    <Label Content="Client:" Height="28" HorizontalAlignment="Left" Margin="0,12,0,0" Name="label1" VerticalAlignment="Top" Width="71" />
    <Label Content="Client Reference:" Height="28" HorizontalAlignment="Left" Margin="0,69,0,0" Name="label2" VerticalAlignment="Top" Width="117" />
    <TextBox  
        x:Name="clientRefTxt"
        Text="{Binding Path=ClientRef, ValidatesOnDataErrors=True, UpdateSourceTrigger=PropertyChanged}"
        Height="23" 
        HorizontalAlignment="Left" 
        Margin="12,103,0,0" 
        VerticalAlignment="Top" 
        Width="174" />
    <Button 
        Content="Search Debtors" 
        Height="23" 
        HorizontalAlignment="Left" 
        Margin="12,140,0,0" 
        Name="button1" 
        VerticalAlignment="Top" 
        Width="89" 
        Command="{Binding Path=SearchCommand}"/>

</Grid>

And I want it to bind to SearchViewModel:

namespace Master.ViewModel
{

public class SearchViewModel:WorkspaceViewModel
{
    RelayCommand _searchCommand;
    readonly Search _search;


    #region Search Properties
    public string ClientRef
    {

        get { MessageBox.Show("GET CLIENTREF"); return _search.ClientRef; }
        set
        {
            MessageBox.Show("SET CLIENTREF");
            if (value == _search.ClientRef)
                return;
            _search.ClientRef = value;
            base.OnPropertyChanged("ClientRef");
        }
    }

    #endregion

    public ICommand SearchCommand
    {
        get
        {
            MessageBox.Show("SEARCHCOMMAND");

            if (_searchCommand == null)
            {
                _searchCommand = new RelayCommand(
                    param=> this.Search(),
                    param=> this.CanSearch
                    );
            }
            return _searchCommand;
        }
    }

    public void Search()
    {
        MessageBox.Show("SEARCHING");
    }

    bool CanSearch
    {
        get { return true; }
    }
}

}

I removed all the assemblies at the top but assume that they are all there. Also note that SearchViewModel is in a separate dll, not in the exe with the View.
Any help would be great or at least a pointer in the write direction, I have already read the msdn article on MVVM and that didnt help…I kinda need a better rundown on binding those too pieces.
Thanks in Advance.
P.S.
Some more details:
SearchViewModel belongs to Master.ViewModel
SearchView is part of GUI.View
I have and idea how the binded objects work, im not to sure on how to bind the view to the viewmodel

Answer 1

Is your View a Grid? I’ve only used UserControl or Window types as Views, but you may have success using a Grid.

Regardless, this is the cleanest way to instantiate the ViewModel with a UserControl View. Just replace the UserControl tags with Grid tags if you’re using a Grid.

<UserControl ...(blah blah)
    xmlns:viewmodel="clr-namespace:Master.ViewModel">
    <UserControl.DataContext>
        <viewmodel:SearchViewModel/>
    </UserControl.DataContext>

I believe keeping out of the View’s code unless necessary is the preferred pattern for MVVM – let the XAML wire things up for you when possible.