public static (UIView NativeView, VisualElement FormsElement) RealizeView(object view, DataTemplate viewTemplate, ItemsView itemsView)
{
if (viewTemplate != null)
{
// Run this through the extension method in case it's really a DataTemplateSelector
viewTemplate = viewTemplate.SelectDataTemplate(view, itemsView);
// We have a template; turn it into a Forms view
var templateElement = viewTemplate.CreateContent() as View;
var renderer = CreateRenderer(templateElement);
// and set the EmptyView as its BindingContext
BindableObject.SetInheritedBindingContext(renderer.Element, view);
return(renderer.NativeView, renderer.Element);
}
if (view is View formsView)
{
// No template, and the EmptyView is a Forms view; use that
var renderer = CreateRenderer(formsView);
return(renderer.NativeView, renderer.Element);
}
return(new UILabel {
Text = $"{view}"
}, null);
}
public override int GetItemViewType(int position)
{
var item = _listItems[position];
DataTemplate dataTemplate = ShellController.GetFlyoutItemDataTemplate(item.Element);
if (item.Element is IMenuItemController)
{
if (DefaultMenuItemTemplate != null && Shell.MenuItemTemplate == dataTemplate)
{
dataTemplate = DefaultMenuItemTemplate;
}
}
else
{
if (DefaultItemTemplate != null && Shell.ItemTemplate == dataTemplate)
{
dataTemplate = DefaultItemTemplate;
}
}
var template = dataTemplate.SelectDataTemplate(item.Element, Shell);
var id = ((IDataTemplateController)template).Id;
_templateMap[id] = template;
return(id);
}
public (UIView NativeView, VisualElement FormsElement) RealizeEmptyView(object emptyView, DataTemplate emptyViewTemplate)
{
if (emptyViewTemplate != null)
{
// Run this through the extension method in case it's really a DataTemplateSelector
emptyViewTemplate = emptyViewTemplate.SelectDataTemplate(emptyView, _itemsView);
// We have a template; turn it into a Forms view
var templateElement = emptyViewTemplate.CreateContent() as View;
var renderer = CreateRenderer(templateElement);
// and set the EmptyView as its BindingContext
BindableObject.SetInheritedBindingContext(renderer.Element, emptyView);
return(renderer.NativeView, renderer.Element);
}
if (emptyView is View formsView)
{
// No template, and the EmptyView is a Forms view; use that
var renderer = CreateRenderer(formsView);
return(renderer.NativeView, renderer.Element);
}
// No template, EmptyView is not a Forms View, so just display EmptyView.ToString
var label = new UILabel {
Text = emptyView.ToString()
};
return(label, null);
}
DataTemplate GetDataTemplate(int viewTypeId)
{
AdapterListItem item = null;
foreach (var ali in _listItems)
{
if (viewTypeId == ali.Index)
{
item = ali;
break;
}
}
DataTemplate dataTemplate = ShellController.GetFlyoutItemDataTemplate(item.Element);
if (item.Element is IMenuItemController)
{
if (DefaultMenuItemTemplate != null && Shell.MenuItemTemplate == dataTemplate)
{
dataTemplate = DefaultMenuItemTemplate;
}
}
else
{
if (DefaultItemTemplate != null && Shell.ItemTemplate == dataTemplate)
{
dataTemplate = DefaultItemTemplate;
}
}
var template = dataTemplate.SelectDataTemplate(item.Element, Shell);
return(template);
}
public override UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
{
int section = indexPath.Section;
int row = indexPath.Row;
var context = Groups[section][row];
DataTemplate template = null;
if (context is MenuItem)
{
template = _context.Shell.MenuItemTemplate ?? DefaultMenuItemTemplate;
}
else
{
template = _context.Shell.ItemTemplate ?? DefaultItemTemplate;
}
var cellId = ((IDataTemplateController)template.SelectDataTemplate(context, _context.Shell)).IdString;
var cell = (UIContainerCell)tableView.DequeueReusableCell(cellId);
if (cell == null)
{
var view = (View)template.CreateContent(context, _context.Shell);
view.Parent = _context.Shell;
cell = new UIContainerCell(cellId, view);
cell.BindingContext = context;
}
else
{
cell.BindingContext = context;
}
return(cell);
}
public void Bind(object itemBindingContext, ItemsView itemsView,
Action <Size> reportMeasure = null, Size?size = null)
{
var template = _template.SelectDataTemplate(itemBindingContext, itemsView);
var templateChanging = template != _selectedTemplate;
if (templateChanging)
{
// Clean up any content we're still holding on to
_itemContentView.Recycle();
// Create the new content
View = (View)template.CreateContent();
// Set the binding context _before_ we create the renderer; that way, the bound data will be
// available during OnElementChanged
View.BindingContext = itemBindingContext;
// Actually create the native renderer
_itemContentView.RealizeContent(View);
_selectedTemplate = template;
}
_itemContentView.HandleItemSizingStrategy(reportMeasure, size);
if (!templateChanging)
{
// Same template, new data
View.BindingContext = itemBindingContext;
}
itemsView.AddLogicalChild(View);
}
public void Bind(DataTemplate template, object bindingContext, ItemsView itemsView)
{
var oldElement = VisualElementRenderer?.Element;
// Run this through the extension method in case it's really a DataTemplateSelector
var itemTemplate = template.SelectDataTemplate(bindingContext, itemsView);
if (itemTemplate != _currentTemplate)
{
// Remove the old view, if it exists
if (oldElement != null)
{
oldElement.MeasureInvalidated -= MeasureInvalidated;
itemsView.RemoveLogicalChild(oldElement);
ClearSubviews();
_size = Size.Zero;
}
// Create the content and renderer for the view
var view = itemTemplate.CreateContent() as View;
// Prevents the use of default color when there are VisualStateManager with Selected state setting the background color
// First we check whether the cell has the default selected background color; if it does, then we should check
// to see if the cell content is the VSM to set a selected color
if (SelectedBackgroundView.BackgroundColor == ColorExtensions.Gray && IsUsingVSMForSelectionColor(view))
{
SelectedBackgroundView = new UIView
{
BackgroundColor = UIColor.Clear
};
}
// Set the binding context _before_ we create the renderer; that way, it's available during OnElementChanged
view.BindingContext = bindingContext;
var renderer = TemplateHelpers.CreateRenderer(view);
SetRenderer(renderer);
// And make the new Element a "child" of the ItemsView
// We deliberately do this _after_ setting the binding context for the new element;
// if we do it before, the element briefly inherits the ItemsView's bindingcontext and we
// emit a bunch of needless binding errors
itemsView.AddLogicalChild(view);
}
else
{
// Same template, different data
var currentElement = VisualElementRenderer?.Element;
if (currentElement != null)
{
currentElement.BindingContext = bindingContext;
}
}
_currentTemplate = itemTemplate;
}
public override UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
{
int section = indexPath.Section;
int row = indexPath.Row;
var context = Groups[section][row];
DataTemplate template = ShellController.GetFlyoutItemDataTemplate(context);
if (context is IMenuItemController)
{
if (DefaultMenuItemTemplate != null && _context.Shell.MenuItemTemplate == template)
{
template = DefaultMenuItemTemplate;
}
}
else
{
if (DefaultItemTemplate != null && _context.Shell.ItemTemplate == template)
{
template = DefaultItemTemplate;
}
}
var cellId = ((IDataTemplateController)template.SelectDataTemplate(context, _context.Shell)).IdString;
UIContainerCell cell;
if (!_cells.TryGetValue(context, out cell))
{
var view = (View)template.CreateContent(context, _context.Shell);
cell = new UIContainerCell(cellId, view);
// Set Parent after binding context so parent binding context doesn't propagate to view
cell.BindingContext = context;
view.Parent = _context.Shell;
}
else
{
var view = _cells[context].View;
cell.Disconnect();
cell = new UIContainerCell(cellId, view);
cell.BindingContext = context;
}
cell.SetAccessibilityProperties(context);
_cells[context] = cell;
cell.TableView = tableView;
cell.IndexPath = indexPath;
cell.ViewMeasureInvalidated += OnViewMeasureInvalidated;
return(cell);
}
public void Bind(object itemBindingContext, ItemsView itemsView)
{
var template = _template.SelectDataTemplate(itemBindingContext, itemsView);
View = (View)template.CreateContent();
_itemContentView.RealizeContent(View);
// Set the binding context before we add it as a child of the ItemsView; otherwise, it will
// inherit the ItemsView's binding context
View.BindingContext = itemBindingContext;
itemsView.AddLogicalChild(View);
}
FrameworkElement RealizeEmptyViewTemplate(object bindingContext, DataTemplate emptyViewTemplate)
{
if (emptyViewTemplate == null)
{
return(new TextBlock {
Text = bindingContext.ToString()
});
}
var template = emptyViewTemplate.SelectDataTemplate(bindingContext, null);
var view = template.CreateContent() as View;
view.BindingContext = bindingContext;
return(RealizeEmptyView(view));
}
public void Bind(DataTemplate template, object bindingContext, ItemsView itemsView)
{
var oldElement = VisualElementRenderer?.Element;
// Run this through the extension method in case it's really a DataTemplateSelector
var itemTemplate = template.SelectDataTemplate(bindingContext, itemsView);
if (itemTemplate != _currentTemplate)
{
// Remove the old view, if it exists
if (oldElement != null)
{
oldElement.MeasureInvalidated -= MeasureInvalidated;
itemsView.RemoveLogicalChild(oldElement);
ClearSubviews();
_size = Size.Zero;
}
// Create the content and renderer for the view
var view = itemTemplate.CreateContent() as View;
// Set the binding context _before_ we create the renderer; that way, it's available during OnElementChanged
view.BindingContext = bindingContext;
var renderer = TemplateHelpers.CreateRenderer(view);
SetRenderer(renderer);
// And make the new Element a "child" of the ItemsView
// We deliberately do this _after_ setting the binding context for the new element;
// if we do it before, the element briefly inherits the ItemsView's bindingcontext and we
// emit a bunch of needless binding errors
itemsView.AddLogicalChild(view);
}
else
{
// Same template, different data
var currentElement = VisualElementRenderer?.Element;
if (currentElement != null)
{
currentElement.BindingContext = bindingContext;
}
}
_currentTemplate = itemTemplate;
}
public override UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
{
int section = indexPath.Section;
int row = indexPath.Row;
var context = Groups[section][row];
DataTemplate template = ShellController.GetFlyoutItemDataTemplate(context);
if (context is IMenuItemController)
{
if (DefaultMenuItemTemplate != null && _context.Shell.MenuItemTemplate == template)
{
template = DefaultMenuItemTemplate;
}
}
else
{
if (DefaultItemTemplate != null && _context.Shell.ItemTemplate == template)
{
template = DefaultItemTemplate;
}
}
var cellId = ((IDataTemplateController)template.SelectDataTemplate(context, _context.Shell)).IdString;
var cell = (UIContainerCell)tableView.DequeueReusableCell(cellId);
if (cell == null)
{
var view = (View)template.CreateContent(context, _context.Shell);
cell = new UIContainerCell(cellId, view);
// Set Parent after binding context so parent binding context doesn't propagate to view
cell.BindingContext = context;
view.Parent = _context.Shell;
}
else
{
cell.BindingContext = context;
}
cell.SetAccessibilityProperties(context);
_views[context] = cell.View;
return(cell);
}
FrameworkElement RealizeEmptyViewTemplate(object bindingContext, DataTemplate emptyViewTemplate)
{
if (emptyViewTemplate == null)
{
return(new TextBlock
{
HorizontalAlignment = Microsoft.UI.Xaml.HorizontalAlignment.Center,
VerticalAlignment = Microsoft.UI.Xaml.VerticalAlignment.Center,
Text = bindingContext.ToString()
});
}
var template = emptyViewTemplate.SelectDataTemplate(bindingContext, null);
var view = template.CreateContent() as View;
view.BindingContext = bindingContext;
return(RealizeEmptyView(view));
}
public void Bind(object itemBindingContext, ItemsView itemsView,
Action <Size> reportMeasure = null, Size?size = null)
{
var template = _template.SelectDataTemplate(itemBindingContext, itemsView);
if (template != _selectedTemplate)
{
_itemContentView.Recycle();
View = (View)template.CreateContent();
_itemContentView.RealizeContent(View);
_selectedTemplate = template;
}
_itemContentView.HandleItemSizingStrategy(reportMeasure, size);
// Set the binding context before we add it as a child of the ItemsView; otherwise, it will
// inherit the ItemsView's binding context
View.BindingContext = itemBindingContext;
itemsView.AddLogicalChild(View);
}
public static (UIView NativeView, VisualElement FormsElement) RealizeView(object view, DataTemplate viewTemplate, ItemsView itemsView)
{
if (viewTemplate != null)
{
// Run this through the extension method in case it's really a DataTemplateSelector
viewTemplate = viewTemplate.SelectDataTemplate(view, itemsView);
// We have a template; turn it into a Forms view
var templateElement = viewTemplate.CreateContent() as View;
// Make sure the Visual property is available when the renderer is created
PropertyPropagationExtensions.PropagatePropertyChanged(null, templateElement, itemsView);
var renderer = GetHandler(templateElement, itemsView.FindMauiContext());
var element = renderer.VirtualView as VisualElement;
// and set the view as its BindingContext
element.BindingContext = view;
return((UIView)renderer.NativeView, element);
}
if (view is View formsView)
{
// Make sure the Visual property is available when the renderer is created
PropertyPropagationExtensions.PropagatePropertyChanged(null, formsView, itemsView);
// No template, and the EmptyView is a Forms view; use that
var renderer = GetHandler(formsView, itemsView.FindMauiContext());
var element = renderer.VirtualView as VisualElement;
return((UIView)renderer.NativeView, element);
}
return(new UILabel {
TextAlignment = UITextAlignment.Center, Text = $"{view}"
}, null);
}
public static object CreateContent(this DataTemplate self, object item, BindableObject container)
{
return(self.SelectDataTemplate(item, container).CreateContent());
}
