WPF treeview with databinding using multiple data sources - wpf

Question

I have a tree view which is used by 2 different sources (Mission, Target) depending on the mode the GUI is in. Only 1 source is displayed at any one time
Class information:
Mission Class
public class Mission
{
public string Name { get; set; }
public List<Target> PotentialTargets { get; set; }
public List<Target> SelectedTargets { get; set; }
public List<Operation> OpList { get; set; }
//other properties
}
Operation Class
public class Operation
{
public string Label { get; set; }
//other properties
}
Target
public class Target
{
public string Label { get; set; }
public TargetType Type { get; set; }
public int Priority { get; set; }
//other properties
}
TargetType
public enum TargetType
{
Star,
Line
}
I am trying to achieve the following display on the TreeView when setting the itemSource to a different source.
Mission Source
- Mission_1(Name)
- Potential_Target
- Target_1(Label)
- Target_2(Label)
- Selected_Target
- Target_1(Label)
- Operation
- Op_1(Name)
- Mission_2(Name)
- Potential_Target
- Target_1(Label)
- Target_4(Label)
- Selected_Target
- Target_4(Label)
- Operation
- Op_1(Name)
Target Source
- Priority_1(Priority)
- Star(TargetType)
- Star_Target_1(Label)
- Line(Type)
- Line_Target_1(Label)
- Priority_2(Priority)
- Star(TargetType)
- Star_Target_2(Label)
- Star_Target_3(Label)
All help will be appreciated.
Thanks in advance.

Answer 1

You need some base class to represent your tree nodes in TreeView.
For example you can declare you classes like this:
ABaseNode
// Base class to provide access to nodes Children
public abstract class ABaseNode
{
private ObservableCollection<ABaseNode> children;
public ObservableCollection<ABaseNode> Children
{
get { return children ?? (children = new ObservableCollection<ABaseNode>()); }
set { children = value; }
}
}
LabeledNode
//Simple node with label to display
public class LabeledNode : ABaseNode
{
public LabeledNode(string label)
{
Label = label;
}
public string Label { get; private set; }
}
Mission Class
public class Mission : LabeledNode
{
public Mission(string label) : base(label)
{
PotentialTargetsNode = new LabeledNode("PotentialTargets");
Children.Add(PotentialTargetsNode);
SelectedTargetsNode = new LabeledNode("SelectedTargets");
Children.Add(SelectedTargetsNode);
OpListNode = new LabeledNode("Operation");
Children.Add(OpListNode);
}
public LabeledNode PotentialTargetsNode { get; private set; }
public LabeledNode SelectedTargetsNode { get; private set; }
public LabeledNode OpListNode { get; private set; }
}
Operation Class
public class Operation : LabeledNode
{
public Operation(string label) : base(label)
{
}
//other properties
}
Target Class
public class Target : LabeledNode
{
public Target(string label) : base(label)
{
}
public TargetType Type { get; set; }
public int Priority { get; set; }
//other properties
}
PriorityNode Class
public class PriorityNode : LabeledNode
{
public PriorityNode(int priority) : base("Priority: " + priority)
{
StarTargetsNode = new LabeledNode("Star");
Children.Add(StarTargetsNode);
LineTargetsNode = new LabeledNode("Line");
Children.Add(LineTargetsNode);
}
public LabeledNode StarTargetsNode { get; private set; }
public LabeledNode LineTargetsNode { get; private set; }
}
Xaml of MainWindow contents
<StackPanel>
<Button Content="Mission source" Click="MissionButtonClick"/>
<Button Content="Target source" Click="TargetsButtonClick"/>
<TreeView x:Name="treeView" Height="250" ItemsSource="{Binding Missions}">
<TreeView.Resources>
<HierarchicalDataTemplate DataType="{x:Type local:LabeledNode}" ItemsSource="{Binding Path=Children}">
<TextBlock Text="{Binding Path=Label}"/>
<HierarchicalDataTemplate.ItemTemplate>
<HierarchicalDataTemplate DataType="{x:Type local:LabeledNode}" ItemsSource="{Binding Children}">
<TextBlock Text="{Binding Label}"/>
</HierarchicalDataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</TreeView.Resources>
</TreeView>
</StackPanel>
Data initialization
public partial class MainWindow : Window
{
public ObservableCollection<Mission> Missions { get; private set; }
public ObservableCollection<PriorityNode> TargetsByPriority { get; private set; }
public MainWindow()
{
InitializeComponent();
var mission = new Mission("Mission1");
mission.PotentialTargetsNode.Children.Add(new Target("Target1") {Type = TargetType.Line, Priority = 1});
mission.PotentialTargetsNode.Children.Add(new Target("Target2") {Type = TargetType.Star, Priority = 2});
mission.SelectedTargetsNode.Children.Add(new Target ("SelectedTarget") { Type = TargetType.Line, Priority = 1 });
mission.OpListNode.Children.Add(new Operation("Op1"));
Missions = new ObservableCollection<Mission> { mission };
var priorityNode = new PriorityNode(1);
priorityNode.StarTargetsNode.Children.Add(new Target("Target3") { Type = TargetType.Star, Priority = 1 });
priorityNode.LineTargetsNode.Children.Add(new Target("Target1") { Type = TargetType.Line, Priority = 1 });
priorityNode.LineTargetsNode.Children.Add(new Target("Target2") { Type = TargetType.Line, Priority = 1 });
TargetsByPriority = new ObservableCollection<PriorityNode> { priorityNode};
DataContext = this;
}
private void MissionButtonClick(object sender, RoutedEventArgs e)
{
treeView.ItemsSource = Missions;
}
private void TargetsButtonClick(object sender, RoutedEventArgs e)
{
treeView.ItemsSource = TargetsByPriority;
}
}
Now click the buttons to change your TreeView ItemsSource.