This is the custom object:
public class FileItem
{
public string Name { get; set; }
public string Path { get; set; }
}
Collection:
public ObservableCollection<FileItem> collection { get; set; }
Combobox:
<ComboBox
Name="cbCollection"
ItemsSource="{Binding interfaces}"/>
ListBox:
<ListBox
Name="lbCollection "
ItemsSource="{Binding collection}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Name}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
So my Combobox is populated with my object collection and i want to see all its properties in my ListBox.
Currently:
I can see only the property Name.
i can see all the objects from my Combobox and not only the selected one.
If you want to see more than just the name property, you'll need to extend the data template to include the additional properties.
If you want to see the selected item's properties, then you should bind to the combo box's SelectedItem property. Actually I don't think you want a ListBox as there is only one selected item.
This should get you started:
<ContentControl Content="{Binding ElementName=cbCollection, Path=SelectedItem}">
<ContentControl.Resources>
<DataTemplate DataType="{x:Type local:FileItem}">
<TextBlock Text="{Binding Name}"/>
</DataTemplate>
</ContentControl.Resources>
</ContentControl>
Related
I am farily new to mvvm so bear with me. I have 2 View models which are inherited namely DBViewModel and PersonViewModel. i would like to add the person object in DBViewModel and bind 2 combobox with observablecollection in PersonViewModel.
public class PersonViewModel
{
private ICommand AddCommand ;
public Person PersonI{get;set;}
public ObservableCollection<Person> EmployeeList{ get; set; }
public ObservableCollection<String> OccupationList{ get; set; }
public PersonViewModel()
{
PersonI = new Person();
this.AddCommand = new DelegateCommand(this.Add);
// get OccupationList and EmployeeList
}
......
}
public class DBViewModel : PersonViewModel
{
public PersonViewModel PersonVM { get; set; }
public PersonViewModel()
{
PersonVM = new PersonViewModel();
}
....
}
<DataTemplate DataType='{x:Type viewModel:DBViewModel}'>
<StackPanel>
<TextBox Text="{Binding PersonI.Name}" />
<ComboBox Name="cboccupation" ItemsSource="{Binding OccupationList}"
DisplayMemberPath="Name"
SelectedItem="{Binding SelectedItem}" SelectedValuePath="Id"/>
<Button Content="Add" Command="{Binding AddCommand}" />
<DataGrid ItemsSource="{Binding EmployeeList}" CanUserAddRows="True">
<DataGrid.Columns>
<DataGridTemplateColumn Header="Occupation">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<ComboBox ItemsSource="{Binding OccupationList}"
DisplayMemberPath="Name" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</StackPanel>
</DataTemplate>
if you want an easier approach I'm thinking you could set a datastore field using blend and bind both controls to that field.
Your bindings are trying to bind to the properties PersonI and OccupationList on the DBViewModel, however those properties do not exist.
You need to point them to the PersonVM.PersonI and PersonVM.OccupationList instead.
<TextBox Text="{Binding PersonVM.PersonI.Name}" />
<ComboBox ItemsSource="{Binding PersonVM.OccupationList}" ... />
For your ComboBox binding inside the DataGrid, that probably will not work because the DataContext of each row in the Grid is a Person object (specified by the DataGrid.ItemsSource), and I don't think Person has a property called OccupationList.
You need to change the Source of your binding to use the object that has the OccupationList property.
For example, if your DataGrid was named MyDataGrid, the following binding for that ComboBox would work
<ComboBox ItemsSource="{Binding
ElementName=MyDataGrid,
Path=DataContext.PersonVM.OccupationList}" ... />
Alternatively, you could use a RelativeSource binding to have it look for the parent DataGrid object without needing to specify a name
<ComboBox ItemsSource="{Binding
RelativeSource={RelativeSource AncestorType={x:Type DataGrid}},
Path=DataContext.PersonVM.OccupationList}" ... />
As a side note, you seem to be a bit confused about bindings and the DataContext. I like to blog about beginner WPF topics, and would recommend reading What is this "DataContext" you speak of?. I find it has helped many WPF beginners on this site understand the basic binding concept. :)
I have an object model like below:
public class ViewModel
{
public List<Group> Groups{ get; set; }
}
public class Group
{
public string Name { get; set; }
public List<Contact> Contacts { get; set; }
}
public class Contact
{
public string Name { get; set; }
public bool IsOnline { get; set; }
}
and I'm binding the groups to an itemscontrol like this:
<ItemsControl ItemsSource="{Binding Path=Groups}"
ItemTemplate="{StaticResource GroupTemplate}" >
</ItemsControl>
and I have datatemplate for rendering them.
<DataTemplate x:Key="GroupTemplate" DataType="{x:Type Group}">
</DataTemplate>
<DataTemplate x:Key="ContactTemplate" DataType="{x:Type Contact}">
<StackPanel>
<TextBlock Text="{Binding Name}"/>
</StackPanle>
</DataTemplate>
How can I get the contacts displayed inside the items control? The contacts is a collection inside each group and my viewmodel has a collection of groups. To complicate it a bit further, I have different datatemplates for different contacts, and I should be using a datatemplateselector for choosing the appropriate contact template. Also please note, I have nothing to display in the group template, and I only need to show Contacts.
Thanks,
-Mike
Use another ItemsControl in the first template:
<DataTemplate x:Key="GroupTemplate" DataType="{x:Type my:Group}">
<ItemsControl ItemsSource="{Binding Contacts}">
<ItemsControl.ItemTemplate>
<DataTemplate DataType="{x:Type my:Contact}">
<TextBlock Text="{Binding Name}"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</DataTemplate>
And with a template selector:
<DataTemplate x:Key="GroupTemplate" DataType="{x:Type my:Group}">
<ItemsControl ItemsSource="{Binding Contacts}"
ItemTemplateSelector="{StaticResource yourContactItemSelector}"/>
</DataTemplate>
We're using Caliburn.Micro/Silverlight 4 and life is good.
I'm trying to bind a combobox's itemsSource to a viewModel, but this doesn't seem possible since the combobox is already bound to its own row's dataItem. The logic which fills the combo changes with other data on the screen so I can't really use a static list like I've been using.
Is there a way to bind directory to the viewModel somehow??? I've tried element to element binding but this never appears to work within the grid.
<Controls:DataGridTemplateColumn x:Name="FooNameCol" Header="Foo" MinWidth="200">
<Controls:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding Path=Foo.ShortName}"
Style="{StaticResource DataGridTextColumnStyle}"/>
</StackPanel>
</DataTemplate>
</Controls:DataGridTemplateColumn.CellTemplate>
<Controls:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<ComboBox DisplayMemberPath="ShortName"
MinWidth="200" MinHeight="25"
SelectedItem="{Binding Path=Officer, Mode=TwoWay, ValidatesOnExceptions=True, NotifyOnValidationError=True}"
ItemsSource="{Binding Officers, Source={StaticResource ReferenceListRetriever}}" />
</DataTemplate>
</Controls:DataGridTemplateColumn.CellEditingTemplate>
</Controls:DataGridTemplateColumn>
Within a DataTemplate, the DataContext is bound to each single item of the corresponding list; since all Bindings implicitly refers to DataContext, you have to ensure that the path is valid, starting from the single data item.
In your scenario, for the indicated binding to work, you should have a VM shaped this way:
public class MyVM {
public IEnumerable<MyItem> Items {get;}
}
public class MyItem {
public Foo Foo {get;}
public Officer Officer {get;set;}
public IEnumerable<Officer> Officers {get;}
}
It may seem an overkill, but in some scenarios each combo can actually contain different choices for each data item, based on some business rule.
In simpler cases MyItem can just expose a common list coming from the parent MyVM:
public class MyItem {
...
public IEnumerable<Officer> Officers {
get { return _parent.AvailableOfficers; }
}
}
If you really can't live with it and prefer to keep the available Officers list in the root VM only, you can use a Xaml side trick:
public class MyVM {
public IEnumerable<MyItem> Items {get;}
public IEnumerable<Officer> Officers {get;}
}
public class MyItem {
public Foo Foo {get;}
public Officer Officer {get;set;}
}
Xaml:
<UserControl ...>
...
<AnyFrameworkElementAtThisLevel Name="bridge" />
...
<Controls:WhateverGrid>
...
<Controls:DataGridTemplateColumn ...>
<Controls:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
...
</DataTemplate>
</Controls:DataGridTemplateColumn.CellTemplate>
<Controls:DataGridTemplateColumn.CellEditingTemplate>
<DataTemplate>
<ComboBox DisplayMemberPath="ShortName"
SelectedItem="{Binding Path=Officer, Mode=TwoWay, ValidatesOnExceptions=True, NotifyOnValidationError=True}"
ItemsSource="{Binding DataContext.Officers, ElementName=bridge}" />
</DataTemplate>
What I need to find is when a textbox's value is changing or the dropdown's value changes inside my datatemplate item, I need to be notified in my ViewModel.cs.
So basically as a user edits a textbox inside the listbox, the viewmodel will be notified as the values are changing.
The reason is I need to go through all my Entries and update something as items inside the listbox's datatemplate change.
Any suggetion?
I have the following in my XAML.
<ListBox x:Name="EntriesListBox"
ItemsSource="{Binding Path=Entries}"
Grid.Row="1">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<ComboBox x:Name="EntriesPropertyName"
Width="215"
Margin="0,0,5,0"
SelectedItem="{Binding Path=Property, Mode=TwoWay}"
ItemsSource="{Binding Source={StaticResource DataContextProxy},Path=DataSource.EntityTypeProperties}" />
<TextBox x:Name="EntriesPropertyValue"
Width="215"
Margin="0,0,5,0"
Text="{Binding Path=Value, Mode=TwoWay, BindsDirectlyToSource=True}" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
The following is in my VM (ViewModel.cs)
public ObservableCollection<Entry> Entries { get; set; }
The following is in my business object (Entry.cs)
public class Entry
{
public PropertyItem Property { get; set; }
public string Value { get; set; }
}
On your binding, set the UpdateSourceTrigger... Also implement INotifyPropertyChanged
Provided that you have setup your view model class properly (by implementing INotifyPropertyChanged), following is what you may want to do:
<TextBox x:Name="EntriesPropertyValue"
Width="215"
Margin="0,0,5,0"
Text="{Binding Path=Value, Mode=TwoWay, BindsDirectlyToSource=True, UpdateSourceTrigger=PropertyChanged}" />
This seems to work. Any reason not to do it this way?
private void EntriesPropertyValue_TextChanged(object sender, TextChangedEventArgs e)
{
(sender as TextBox).GetBindingExpression(TextBox.TextProperty).UpdateSource();
this.ViewModel.UpdateFinalQuery();
}
I have one Listbox and applied one DataTemplate like this
<ListBox>
<ListBox.ItemTemplate>
<Grid>
<TextBlock Text="{Binding Path=Name}" Grid.Row=0/>
<ComoboBox Name="test"
DisplayMemberPath="Country"
SelectedValuePath="Country_ID">
</Grid>
How will I load ItemSource to this ComboBox dynamically based on each item selected in the ListBox? Iam new to WPF... pls help with your valuable suggestions.
<ListBox>
<ListBox.ItemTemplate>
<Grid>
<TextBlock Text="{Binding Path=Name}" Grid.Row=0/>
<ComoboBox Name="test"
DataContent="{Binding RelativeSource={RelativeSource AncestorType=ListBox}}"
ItemsSource="{Binding}"
DisplayMemberPath="Country"
SelectedValuePath="Country_ID">
</Grid>
Now your combocbox is always have the same itemssource as the parent listbox.
One way to do this is to bind the ItemsSource of your ComboBox to the SelectedValue property of the ListBox. For this to work the ListBox needs to be bound to a collection of items that contains a list of items that the ComboBox will bind to.
<ListBox
x:Name="CategoryList"
ItemsSource="{Binding Path=MasterList,
RelativeSource={RelativeSource AncestorType=Window}}"
DisplayMemberPath="MasterProperty"
SelectedValuePath="Details"
/>
<ComboBox
ItemsSource="{Binding Path=SelectedValue, ElementName=CategoryList}"
DisplayMemberPath="DetailProperty"
Grid.Row="1"
/>
In this example I have created a public property in the code behind of the window that exposes a list of objects containing the Details collection.
public List<Master> MasterList { get; set; }
public class Master
{
public string MasterProperty { get; set; }
public List<Detail> Details { get; set; }
}
public class Detail
{
public string DetailProperty { get; set; }
}