/// <summary>
/// Capture property changes made by the user and return the design time value.
/// </summary>
/// <param name="item">The model item for a TabControl.</param>
/// <param name="identifier">The property that the user is changing the value of.</param>
/// <param name="value">The new value that the user is giving the property.</param>
/// <returns>The value to set the property to in the designer.</returns>
public override object TranslatePropertyValue(ModelItem item, PropertyIdentifier identifier, object value)
{
if (identifier == MyPlatformTypes.TabControl.SelectedIndexProperty)
{
// if SelectedIndex has been modified from XAML/PB, we use that as the value for selectedIndex
// otherwise we determine the index of active tabItem and return that as the selected Index
// TabControl's DMVP gets called when user changes SelectedIndex from XAML/PB and whenever TabControl gets created/recreated.
// TabControl gets recreated when its items collection is updated (adding/removing tabs)
// **************Scenario 1:TabItem is added/removed
// When a tabItem is added or removed, TabItemAdornerProvider updates the selection for TabItems and we want to retain that selection
// This is done by updating DesignTimeSelectedIndex value each time selection for Tabitem is updated and we use this value in TabControls DMVP
// *************Scenario 2:User hasa updated SelectedIndex value from XAML/PB
// Here we want to use the updated value of SelectedIndex that gets passed into TabControl DMVP
// To distinguish between the scenario where Tabcontrol is recreated(Scenario 1) and the case where user has simply updated SelectedIndex property value
// we maintain another DesignerProperty called as CurrentSelectedIndexValueProperty, which stores current value of SelectedIndex that has been serialized
// We compare CurrentSelectedIndexValueProperty with new value that is passed in to determine whether user has updated SelectedIndex from XAML/PB
// If this is the case, we should use updated value of SelectedIndex that user has set and update TabItem selection too
if (GetCurrentSelectedIndexPropertyValue(item) != (int)value)
{
// this is Scenario 2: User has updated SelectedIndex value from XAML/PB
SetCurrentSelectedIndexPropertyValue(item, (int)value);
if (item.Content.Collection != null && (int)value >= 0 && (int)value < item.Content.Collection.Count)
{
ModelItem tabItem = item.Content.Collection[(int)value];
TabItemDesignModeValueProvider.SetDesignTimeIsSelected(tabItem, true);
return(value);
}
}
// If control flows till here, then its Scenario 1: TabItem is added/removed
int selectedIndex = GetDesignTimeSelectedIndex(item);
if (selectedIndex != -1)
{
return(selectedIndex);
}
else if (item.Properties[identifier].IsSet)
{
return(value);
}
else
{
return(0);
}
}
return(base.TranslatePropertyValue(item, identifier, value));
}
/// <summary>
/// Get the value of SelectedIndex.
/// </summary>
/// <param name="item">The model item for a TabControl.</param>
/// <returns>SelectedIndex of the TabControl.</returns>
public static int GetDesignTimeSelectedIndex(ModelItem item)
{
int selectedIndex = item.GetDesignerProperty(DesignTimeSelectedIndexProperty);
// check if that tab is really active. If not, then return -1 (none of the tabs are active
if (item.Content != null &&
item.Content.Collection.Count > 0 &&
selectedIndex < item.Content.Collection.Count)
{
if (TabItemDesignModeValueProvider.GetDesignTimeIsSelected(item.Content.Collection[selectedIndex]))
{
return(selectedIndex);
}
}
return(-1);
}
/// <summary>
/// When this TabItem is activated set IsSelected to true.
/// </summary>
/// <param name="item">A ModelItem representing the adorned element.</param>
protected override void Activate(ModelItem item)
{
if (item != null && item.IsItemOfType(MyPlatformTypes.TabItem.TypeId))
{
if (Context != null)
{
Tool tool = Context.Items.GetValue <Tool>();
if (tool == null || tool.FocusedTask == null)
{
TabItemDesignModeValueProvider.SetDesignTimeIsSelected(item, true); // activate the tab that has been selected
item.View.UpdateLayout();
}
}
}
base.Activate(item);
}
/// <summary>
/// Set the value of SelectedIndex and raise change notification.
/// Make the selected TabItem the Active TabItem.
/// </summary>
/// <param name="item">Model item for the TabControl.</param>
/// <param name="value">The SelectedIndex value.</param>
public static void SetDesignTimeSelectedIndex(ModelItem item, int value)
{
item.SetDesignerProperty(DesignTimeSelectedIndexProperty, value);
Util.InvalidateProperty(item, MyPlatformTypes.TabControl.SelectedIndexProperty);
ModelProperty content = item.Content;
ModelItemCollection tabControlChildCollection = null;
// activate the corresponding TabItem
if (content != null)
{
tabControlChildCollection = content.Collection;
if (tabControlChildCollection != null && value <= tabControlChildCollection.Count)
{
TabItemDesignModeValueProvider.SetDesignTimeIsSelected(tabControlChildCollection[value], true);
}
}
}
/// <summary>
/// Determine how the control is parented into the TabItem.
/// If the control is a TabItem then parent it to the TabControl rather
/// than the TabItem (think select, copy, paste a TabItem).
/// If the TabItem has content and the content can accept children
/// then parent into that and so on.
/// </summary>
/// <param name="parent">The parent item.</param>
/// <param name="childType">The type of child item.</param>
/// <returns>Redirected parent.</returns>
public override ModelItem RedirectParent(ModelItem parent, Type childType)
{
_canParent = true;
if (parent == null)
{
throw new ArgumentNullException("parent");
}
if (childType == null)
{
throw new ArgumentNullException("childType");
}
// if the tabItem is not activated and/or not within TabControl,
// redirect to its parent by returning ourselves.
if (parent.IsItemOfType(MyPlatformTypes.TabItem.TypeId) &&
parent.Parent != null &&
(!parent.Parent.IsItemOfType(MyPlatformTypes.TabControl.TypeId) || !TabItemDesignModeValueProvider.GetDesignTimeIsSelected(parent)))
{
_canParent = false;
return(parent);
}
// if element being parented is tabItem then add it as sibling of
// existing tabItems inside TabControl - redirect to parent;
// else parent this control in TabItem's content, if its Panel.
if (ModelFactory.ResolveType(parent.Context, MyPlatformTypes.TabItem.TypeId).IsAssignableFrom(childType))
{
_canParent = false;
return(parent);
}
if (parent.Content != null && parent.Content.IsSet)
{
// if TabItem has a content and if the content is a panel or a contentcontrol,
// let the content act as the parent.
ModelItem content = parent.Content.Value;
if (content != null)
{
ViewItem contentView = content.View;
if (content.View != null)
{
// if the content is not visible but the tabItem is selected,
// Update this TabItems Layout.
if (!contentView.IsVisible && TabItemDesignModeValueProvider.GetDesignTimeIsSelected(parent))
{
parent.View.UpdateLayout();
}
if (contentView.IsVisible &&
(content.IsItemOfType(MyPlatformTypes.Panel.TypeId) || content.IsItemOfType(MyPlatformTypes.ContentControl.TypeId)))
{
return(content);
}
}
else
{
// TabItem has a content already but the content cannot accept parenting right now
// so let tabItem's parent take care of parenting.
_canParent = false;
return(parent);
}
}
}
// TabItem doesnt have any content and now tabItem itself acts as the parent.
return(base.RedirectParent(parent, childType));
}
/// <summary>
/// Parent the given control into the TabControl.
/// </summary>
/// <param name="parent">The new parent item for child.</param>
/// <param name="child">The child item.</param>
public override void Parent(ModelItem parent, ModelItem child)
{
if (parent == null)
{
throw new ArgumentNullException("parent");
}
if (child == null)
{
throw new ArgumentNullException("child");
}
// Clear existing property values that we don't want to apply to the new container.
child.Properties[MyPlatformTypes.FrameworkElement.MarginProperty].ClearValue();
child.Properties[MyPlatformTypes.FrameworkElement.HorizontalAlignmentProperty].ClearValue();
child.Properties[MyPlatformTypes.FrameworkElement.VerticalAlignmentProperty].ClearValue();
bool childIsTabItem = child.IsItemOfType(MyPlatformTypes.TabItem.TypeId);
// We always accept parenting in TabControl if there is not active focused Task.
// If the control being pasted is not TabItem and TabControl is empty (doesnt have any TabItem(s) in it)
// then we inject a TabItem with Grid in TabControl and paste the control under consideration in TabItem.
// We inject a TabItem also in cases when active TabItem is not capable of parenting concerned control
if (!childIsTabItem)
{
// Based on evaluation done in RedirectParent(),
// if any control other than TabItem is being parented to Control in this Parent() call
// then we need to add a new Tabitem with Grid in it
try
{
ModelItem newTabItem = ModelFactory.CreateItem(parent.Context, MyPlatformTypes.TabItem.TypeId, CreateOptions.InitializeDefaults);
parent.Content.Collection.Add(newTabItem);
// activate the newly added tabItem
TabItemDesignModeValueProvider.SetDesignTimeIsSelected(newTabItem, true);
int index = parent.Content.Collection.Count - 1;
// Find a suitable parent for control to be pasted.
// Since we always accept parenting for TabControl when there is no active focused task,
// we better make sure this works.
AdapterService adapterService = parent.Context.Services.GetService <AdapterService>();
if (adapterService != null)
{
ModelItem targetParent = FindSuitableParent(adapterService, parent, child.ItemType, index);
if (targetParent != null)
{
ParentAdapter parentAdapter = adapterService.GetAdapter <ParentAdapter>(targetParent.ItemType);
parentAdapter.Parent(targetParent, child);
}
else
{
Debug.Assert(targetParent != null, "Parenting failed!");
}
}
}
catch (Exception ex)
{
throw new InvalidOperationException("Parenting Failed", ex.InnerException);
}
}
else
{
// child being added is a TabItem;
child.Properties[MyPlatformTypes.TabItem.IsSelectedProperty].ClearValue();
parent.Content.Collection.Add(child);
TabItemDesignModeValueProvider.SetDesignTimeIsSelected(child, true); // Activate the newly added tabItem
}
}