Class

RadCollectionView

Initializes a new instance of the RadCollectionView class with default settings. Creates an empty collection view ready to be configured with data source, layout, and templates.

Declaration

public RadCollectionView()

Identifies the AutoExpandGroups bindable property.

Declaration

public static readonly BindableProperty AutoExpandGroupsProperty

Field Value

Identifies the AutomaticLoadOnDemandTemplate bindable property.

Declaration

public static readonly BindableProperty AutomaticLoadOnDemandTemplateProperty

Field Value

Identifies the CurrentItem bindable property.

Declaration

public static readonly BindableProperty CurrentItemProperty

Field Value

Identifies the DisplayMemberPath bindable property.

Declaration

public static readonly BindableProperty DisplayMemberPathProperty

Field Value

Identifies the DragDropBehavior dependency property.

Declaration

public static readonly BindableProperty DragDropBehaviorProperty

Field Value

Identifies the DragVisualTemplate dependency property.

Declaration

public static readonly BindableProperty DragVisualTemplateProperty

Field Value

Identifies the DropIndicatorTemplate dependency property.

Declaration

public static readonly BindableProperty DropIndicatorTemplateProperty

Field Value

Identifies the EmptyContentDisplayMode bindable property.

Declaration

public static readonly BindableProperty EmptyContentDisplayModeProperty

Field Value

Identifies the EmptyContentTemplate bindable property.

Declaration

public static readonly BindableProperty EmptyContentTemplateProperty

Field Value

Identifies the EnableStickyGroupHeaders bindable property.

Declaration

public static readonly BindableProperty EnableStickyGroupHeadersProperty

Field Value

Identifies the EndItemSwipeCommand dependency property.

Declaration

public static readonly BindableProperty EndItemSwipeCommandProperty

Field Value

Identifies the EndSwipeLength dependency property.

Declaration

public static readonly BindableProperty EndSwipeLengthProperty

Field Value

Identifies the EndSwipeTemplate dependency property.

Declaration

public static readonly BindableProperty EndSwipeTemplateProperty

Field Value

Identifies the FilterDescriptors bindable property.

Declaration

public static readonly BindableProperty FilterDescriptorsProperty

Field Value

Identifies the FooterTemplate bindable property.

Declaration

public static readonly BindableProperty FooterTemplateProperty

Field Value

Identifies the GroupDescriptors bindable property.

Declaration

public static readonly BindableProperty GroupDescriptorsProperty

Field Value

Identifies the GroupHeaderTemplate bindable property.

Declaration

public static readonly BindableProperty GroupHeaderTemplateProperty

Field Value

Identifies the GroupTapCommand bindable property.

Declaration

public static readonly BindableProperty GroupTapCommandProperty

Field Value

Identifies the GroupViewStyle bindable property.

Declaration

public static readonly BindableProperty GroupViewStyleProperty

Field Value

Identifies the GroupViewStyleSelector bindable property.

Declaration

public static readonly BindableProperty GroupViewStyleSelectorProperty

Field Value

Identifies the HeaderTemplate bindable property.

Declaration

public static readonly BindableProperty HeaderTemplateProperty

Field Value

Identifies the HorizontalScrollBarVisibility bindable property.

Declaration

public static readonly BindableProperty HorizontalScrollBarVisibilityProperty

Field Value

Identifies the IsDragDropEnabled dependency property.

Declaration

public static readonly BindableProperty IsDragDropEnabledProperty

Field Value

Identifies the IsItemSwipeEnabled dependency property.

Declaration

public static readonly BindableProperty IsItemSwipeEnabledProperty

Field Value

Identifies the IsLoadOnDemandActive bindable property.

Declaration

public static readonly BindableProperty IsLoadOnDemandActiveProperty

Field Value

Identifies the IsLoadOnDemandEnabled bindable property.

Declaration

public static readonly BindableProperty IsLoadOnDemandEnabledProperty

Field Value

Identifies the ItemTapCommand bindable property.

Declaration

public static readonly BindableProperty ItemTapCommandProperty

Field Value

Identifies the ItemTemplate bindable property.

Declaration

public static readonly BindableProperty ItemTemplateProperty

Field Value

Identifies the ItemViewStyle bindable property.

Declaration

public static readonly BindableProperty ItemViewStyleProperty

Field Value

Identifies the ItemViewStyleSelector bindable property.

Declaration

public static readonly BindableProperty ItemViewStyleSelectorProperty

Field Value

Identifies the ItemsLayout bindable property.

Declaration

public static readonly BindableProperty ItemsLayoutProperty

Field Value

Identifies the ItemsSource bindable property.

Declaration

public static readonly BindableProperty ItemsSourceProperty

Field Value

Identifies the LoadOnDemandBufferItemsCount bindable property.

Declaration

public static readonly BindableProperty LoadOnDemandBufferItemsCountProperty

Field Value

Identifies the LoadOnDemandCommand bindable property.

Declaration

public static readonly BindableProperty LoadOnDemandCommandProperty

Field Value

Identifies the LoadOnDemandMode bindable property.

Declaration

public static readonly BindableProperty LoadOnDemandModeProperty

Field Value

Identifies the ManualLoadOnDemandTemplate bindable property.

Declaration

public static readonly BindableProperty ManualLoadOnDemandTemplateProperty

Field Value

Identifies the SelectedIndex bindable property.

Declaration

public static readonly BindableProperty SelectedIndexProperty

Field Value

Identifies the SelectedItem bindable property.

Declaration

public static readonly BindableProperty SelectedItemProperty

Field Value

Identifies the SelectedItems bindable property.

Declaration

public static readonly BindableProperty SelectedItemsProperty

Field Value

Identifies the SelectionMode bindable property.

Declaration

public static readonly BindableProperty SelectionModeProperty

Field Value

Identifies the SortDescriptors bindable property.

Declaration

public static readonly BindableProperty SortDescriptorsProperty

Field Value

Identifies the StartSwipeLength dependency property.

Declaration

public static readonly BindableProperty StartSwipeLengthProperty

Field Value

Identifies the StartSwipeTemplate dependency property.

Declaration

public static readonly BindableProperty StartSwipeTemplateProperty

Field Value

Identifies the SwipeCompletedCommand dependency property.

Declaration

public static readonly BindableProperty SwipeCompletedCommandProperty

Field Value

Identifies the SwipeStartingCommand dependency property.

Declaration

public static readonly BindableProperty SwipeStartingCommandProperty

Field Value

Identifies the SwipeThreshold dependency property.

Declaration

public static readonly BindableProperty SwipeThresholdProperty

Field Value

Identifies the SwipingCommand dependency property.

Declaration

public static readonly BindableProperty SwipingCommandProperty

Field Value

Identifies the VerticalScrollBarVisibility bindable property.

Declaration

public static readonly BindableProperty VerticalScrollBarVisibilityProperty

Field Value

Gets or sets a value indicating whether groups in the control are automatically expanded.

Declaration

public bool AutoExpandGroups { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual representation of the loading indicator in Automatic mode. This template is used to create the loading indicator shown while data is being loaded automatically.

Declaration

public DataTemplate AutomaticLoadOnDemandTemplate { get; set; }

Property Value

Gets or sets the current item in the collection view for keyboard navigation purposes. This is primarily used on desktop platforms to track which item has keyboard focus. The current item is visually highlighted and can be navigated using arrow keys.

Declaration

public object CurrentItem { get; set; }

Property Value

Gets or sets the path to a property on the source object that will be used as the visual representation of the item. When ItemTemplate is not specified, this property path will be used to display text for each item.

Declaration

public string DisplayMemberPath { get; set; }

Property Value

Gets or sets the custom behavior that controls drag and drop operations for collection view items. This behavior allows you to override the default drag and drop logic with custom handling for drag validation, drop positioning, and data manipulation.

Declaration

public CollectionViewDragDropBehavior DragDropBehavior { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual representation of an item while it is being dragged. This template determines how the dragged item appears as it follows the user's finger or cursor during the drag operation.

Declaration

public DataTemplate DragVisualTemplate { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual appearance of the drop indicator. The drop indicator is shown between items during drag and drop operations to indicate where the dragged item will be placed.

Declaration

public DataTemplate DropIndicatorTemplate { get; set; }

Property Value

Gets or sets a value that determines when the EmptyContentTemplate will be displayed. Options include showing when ItemsSource is null, or when it's null or empty.

Declaration

public EmptyContentDisplayMode EmptyContentDisplayMode { get; set; }

Property Value

Gets or sets the DataTemplate that defines the content displayed when the collection view has no items to show. The visibility is controlled by the EmptyContentDisplayMode property.

Declaration

public DataTemplate EmptyContentTemplate { get; set; }

Property Value

Gets or sets a value indicating whether group headers remain fixed (sticky) at the top of the collection view while scrolling through group content. This feature is supported on iOS and Android platforms only.

Declaration

public bool EnableStickyGroupHeaders { get; set; }

Property Value

Gets the command that can be used to programmatically close any currently swiped item and return it to its normal position. This command is useful for closing swipe views from external code or user interface elements. When you execute this command you need to pass a bool parameter, and its value should be true if you want the view to be moved back to its normal position with an animation.

Declaration

public ICommand EndItemSwipeCommand { get; }

Property Value

Gets or sets the width that a swiped item retains when swiped from the end edge (right in LTR, left in RTL). This determines how much of the end swipe template remains visible after the swipe completes.

Declaration

public double EndSwipeLength { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual content displayed when an item is swiped from the end edge. In vertical orientation, this appears when swiping right; in horizontal orientation, when swiping down.

Declaration

public DataTemplate EndSwipeTemplate { get; set; }

Property Value

Gets the collection of FilterDescriptorBase objects that define the filtering criteria for the collection view. All filter descriptors are applied simultaneously to determine which items are visible.

Declaration

public FilterDescriptorCollection FilterDescriptors { get; }

Property Value

Gets or sets the DataTemplate that will be displayed at the end of the collection view content. This footer appears after all items and groups in the scrollable area.

Declaration

public DataTemplate FooterTemplate { get; set; }

Property Value

Gets the collection of GroupDescriptorBase objects that define the grouping criteria for the collection view. Multiple group descriptors create a hierarchical grouping structure with multiple group levels.

Declaration

public GroupDescriptorCollection GroupDescriptors { get; }

Property Value

Gets or sets the DataTemplate that defines the visual representation of group headers. Can be a DataTemplate or DataTemplateSelector for custom template selection logic. Only applicable when grouping is enabled via GroupDescriptors.

Declaration

public DataTemplate GroupHeaderTemplate { get; set; }

Property Value

Gets or sets the command that is executed when a group header is tapped. The command parameter is the GroupContext of the tapped group header.

Declaration

public ICommand GroupTapCommand { get; set; }

Property Value

Gets or sets the Style that is applied to the container element generated for each group header. This style is applied to RadCollectionViewGroupView instances.

Declaration

public Style GroupViewStyle { get; set; }

Property Value

Gets or sets the style selector that provides custom style-selection logic for group header container elements. Allows applying different styles to different group headers based on their group context or other criteria.

Declaration

public IStyleSelector GroupViewStyleSelector { get; set; }

Property Value

Gets or sets the DataTemplate that will be displayed at the beginning of the collection view content. This header appears before all items and groups in the scrollable area.

Declaration

public DataTemplate HeaderTemplate { get; set; }

Property Value

Gets or sets the visibility of the horizontal scroll bar. Controls when the horizontal scroll indicator is shown during scrolling.

Declaration

public ScrollBarVisibility HorizontalScrollBarVisibility { get; set; }

Property Value

Gets or sets a value indicating whether drag and drop functionality is enabled for collection view items. When enabled, users can drag items to reorder them within the collection or move them to other drop targets.

Declaration

public bool IsDragDropEnabled { get; set; }

Property Value

Gets or sets a value indicating whether items in the collection view can be swiped to reveal additional content or actions. When enabled, users can swipe items left or right to access swipe templates.

Declaration

public bool IsItemSwipeEnabled { get; set; }

Property Value

Gets or sets a value indicating whether an asynchronous load-on-demand operation is currently in progress. This property is automatically managed when using LoadOnDemandCollection<T>. When handling LoadOnDemand event or LoadOnDemandCommand manually, set this to true before starting async operations and false after completing them to prevent multiple concurrent requests.

Declaration

public bool IsLoadOnDemandActive { get; set; }

Property Value

Gets or sets a value indicating whether the load-on-demand feature is enabled. When enabled, the collection view can automatically or manually trigger loading of additional items as the user scrolls or interacts with the control. Use the LoadOnDemand event or LoadOnDemandCommand to handle loading requests, or use LoadOnDemandCollection<T> as ItemsSource.

Declaration

public bool IsLoadOnDemandEnabled { get; set; }

Property Value

Gets or sets the command that is executed when a collection view item is tapped. The command parameter is the data context of the tapped item.

Declaration

public ICommand ItemTapCommand { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual representation of items in the collection view. Can be a DataTemplate or DataTemplateSelector for custom template selection logic.

Declaration

public DataTemplate ItemTemplate { get; set; }

Property Value

Gets or sets the Style that is applied to the container element generated for each item. This style is applied to RadCollectionViewItemView instances.

Declaration

public Style ItemViewStyle { get; set; }

Property Value

Gets or sets the style selector that provides custom style-selection logic for item container elements. Allows applying different styles to different items based on their data context or other criteria.

Declaration

public IStyleSelector ItemViewStyleSelector { get; set; }

Property Value

Gets or sets the layout strategy that defines how items are arranged and displayed in the collection view. Supports linear layouts (CollectionViewLinearLayout) and grid layouts (CollectionViewGridLayout).

Declaration

public CollectionViewLayoutBase ItemsLayout { get; set; }

Property Value

Gets or sets the data source used to generate the content of the collection view. This can be any object that implements IEnumerable, such as a list, array, or observable collection.

Declaration

public object ItemsSource { get; set; }

Property Value

Gets or sets the number of items before the end of the current data that will trigger automatic load-on-demand. This property only applies when LoadOnDemandMode is set to Automatic. A larger value will trigger loading earlier as the user scrolls towards the end.

Declaration

public int LoadOnDemandBufferItemsCount { get; set; }

Property Value

Gets or sets the command that is executed when a load-on-demand operation is triggered. In Manual mode, this command is executed when the user clicks the load more button. In Automatic mode, this command is executed when the user scrolls near the end of the current items.

Declaration

public ICommand LoadOnDemandCommand { get; set; }

Property Value

Gets or sets the mode that determines how load-on-demand operations are triggered. Manual mode displays a clickable button, while Automatic mode triggers loading based on scroll position.

Declaration

public LoadOnDemandMode LoadOnDemandMode { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual representation of the load-on-demand control in Manual mode. This template is used to create the button or control that users click to load more items.

Declaration

public DataTemplate ManualLoadOnDemandTemplate { get; set; }

Property Value

Gets or sets the zero-based index of the currently selected item. Returns -1 when no item is selected. In multiple selection mode, returns the index of the first item in the SelectedItems collection.

Declaration

public int SelectedIndex { get; set; }

Property Value

Gets or sets the currently selected item from the data source. Returns null when no item is selected. In multiple selection mode, returns the first item in the SelectedItems collection.

Declaration

public object SelectedItem { get; set; }

Property Value

Gets the collection of currently selected items from the data source. This collection is automatically updated when the selection changes and supports notifications.

Declaration

public ObservableCollection<object> SelectedItems { get; }

Property Value

Gets or sets the selection mode that determines how items can be selected in the collection view. Options include None (no selection), Single (one item), or Multiple (multiple items).

Declaration

public CollectionViewSelectionMode SelectionMode { get; set; }

Property Value

Gets the collection of SortDescriptorBase objects that define the sorting criteria for the collection view. Multiple sort descriptors create a multi-level sorting operation where subsequent descriptors are used as tie-breakers.

Declaration

public SortDescriptorCollection SortDescriptors { get; }

Property Value

Gets or sets the width that a swiped item retains when swiped from the start edge (left in LTR, right in RTL). This determines how much of the start swipe template remains visible after the swipe completes.

Declaration

public double StartSwipeLength { get; set; }

Property Value

Gets or sets the DataTemplate that defines the visual content displayed when an item is swiped from the start edge. In vertical orientation, this appears when swiping left; in horizontal orientation, when swiping up.

Declaration

public DataTemplate StartSwipeTemplate { get; set; }

Property Value

Gets or sets the command that is executed when an item swipe gesture has been completed. This is called after the user has finished the swipe gesture and the final state has been determined. The parameter of this command is of type CollectionViewSwipeCompletedCommandContext.

Declaration

public ICommand SwipeCompletedCommand { get; set; }

Property Value

Gets or sets the command that is executed when an item swipe gesture is about to begin. This provides an opportunity to perform custom logic or cancel the swipe operation. The parameter of this command is of type CollectionViewSwipeStartingCommandContext.

Declaration

public ICommand SwipeStartingCommand { get; set; }

Property Value

Gets or sets the minimum distance (in pixels) that a user must swipe to trigger the swipe feature. A smaller threshold makes swipes more sensitive, while a larger threshold requires more deliberate gestures.

Declaration

public double SwipeThreshold { get; set; }

Property Value

Gets or sets the command that is executed continuously while an item is being swiped. This provides real-time feedback during the swipe gesture. The parameter of this command is of type CollectionViewSwipingCommandContext.

Declaration

public ICommand SwipingCommand { get; set; }

Property Value

Gets or sets the visibility of the vertical scroll bar. Controls when the vertical scroll indicator is shown during scrolling.

Declaration

public ScrollBarVisibility VerticalScrollBarVisibility { get; set; }

Property Value

Programmatically closes any currently swiped item and returns it to its normal position. This method provides direct control over the swipe state without requiring user interaction.

Declaration

public void EndItemSwipe(bool animate = true, Action animationFinished = null)

Parameters

Gets an IDataViewCollection instance that provides access to the processed data after all sorting, grouping, and filtering operations have been applied. This allows you to traverse and manipulate the data as it appears in the collection view.

Declaration

public IDataViewCollection GetDataView()

Returns

Invoked whenever the binding context of the control changes.

Declaration

protected override void OnBindingContextChanged()

Declaration

protected override void OnHandlerChanged()

Declaration

protected override void OnPropertyChanged(string propertyName = null)

Parameters

Scrolls the collection view to bring the specified data item into the visible area. If the item is not currently loaded due to data virtualization, this method will attempt to locate and scroll to it.

Declaration

public void ScrollItemIntoView(object item, bool animate = true)

Parameters

Occurs when a user taps on a group header. The event provides the group context that was tapped.

Declaration

public event EventHandler<RadTappedEventArgs<GroupContext>> GroupTapped

Event Value

Occurs when a user is in the process of tapping on a group header. This event is raised before the GroupTapped event and can be cancelled.

Declaration

public event EventHandler<RadTappingEventArgs<GroupContext>> GroupTapping

Event Value

Occurs when a user taps on a collection view item. The event provides the tapped item's data context.

Declaration

public event EventHandler<RadTappedEventArgs<object>> ItemTapped

Event Value

Occurs when additional items need to be loaded into the collection view. In Manual mode, this event is raised when the user taps the load more button. In Automatic mode, this event is raised when the user scrolls near the end of the current items. Use LoadOnDemandCollection<T> as ItemsSource for automatic loading indicators, or manually handle this event by setting IsLoadOnDemandActive to true before async operations and false after adding new items to the ItemsSource.

Declaration

public event EventHandler<EventArgs> LoadOnDemand

Event Value

Occurs when the collection view is scrolled. Provides information about the scroll position and offset.

Declaration

public event EventHandler<ScrolledEventArgs> Scrolled

Event Value

Occurs when the selection in the collection view changes. Provides information about added and removed items from the selection.

Declaration

public event EventHandler<RadSelectionChangedEventArgs> SelectionChanged

Event Value

Occurs when an item swipe gesture has been completed. This event is raised after the user has finished the swipe gesture and provides the final swipe state.

Declaration

public event EventHandler<CollectionViewSwipeCompletedEventArgs> SwipeCompleted

Event Value

Occurs when an item swipe gesture is about to begin. This event provides an opportunity to cancel the swipe operation before it starts.

Declaration

public event EventHandler<CollectionViewSwipeStartingEventArgs> SwipeStarting

Event Value

Occurs while an item is being swiped. This event is raised continuously during the swipe gesture and provides real-time swipe information.

Declaration

public event EventHandler<CollectionViewSwipingEventArgs> Swiping

Event Value