Class GridView

A view containing recycled rows with items inside.

Inheritance
object
CallbackEventHandler
Focusable
VisualElement
BindableElement
GridView
Implements
Inherited Members
VisualElement.ExecuteDefaultAction(EventBase)
VisualElement.Focus()
VisualElement.Overlaps(Rect)
VisualElement.ToString()
VisualElement.GetFirstOfType<T>()
VisualElement.GetFirstAncestorOfType<T>()
VisualElement.canGrabFocus
VisualElement.focusController
VisualElement.cacheAsBitmap
CallbackEventHandler.RegisterCallback<TEventType>(EventCallback<TEventType>, TrickleDown)
CallbackEventHandler.RegisterCallback<TEventType, TUserArgsType>(EventCallback<TEventType, TUserArgsType>, TUserArgsType, TrickleDown)
CallbackEventHandler.UnregisterCallback<TEventType>(EventCallback<TEventType>, TrickleDown)
CallbackEventHandler.UnregisterCallback<TEventType, TUserArgsType>(EventCallback<TEventType, TUserArgsType>, TrickleDown)
Namespace: Unity.AppUI.UI
Assembly: Unity.AppUI.dll
Syntax
public class GridView : BindableElement, IEventHandler, IVisualElementScheduler, IExperimentalFeatures, ITransitionAnimations, ITransform, IResolvedStyle, IBindable, ISerializationCallbackReceiver

Constructors

GridView()

Creates a GridView with all default properties. The itemsSource, itemHeight, makeItem and bindItem properties must all be set for the GridView to function properly.

Declaration
public GridView()

GridView(IList, Func<VisualElement>, Action<VisualElement, int>)

Constructs a GridView, with all required properties provided.

Declaration
public GridView(IList itemsSource, Func<VisualElement> makeItem, Action<VisualElement, int> bindItem)
Parameters
Type Name Description
IList itemsSource

The list of items to use as a data source.
Func<VisualElement> makeItem

The factory method to call to create a display item. The method should return a VisualElement that can be bound to a data item.
Action<VisualElement, int> bindItem

The method to call to bind a data item to a display item. The method receives as parameters the display item to bind, and the index of the data item to bind it to.

Fields

ussClassName

The USS class name for GridView elements.

Declaration
public const string ussClassName = "appui-grid-view"
Field Value
Type Description
string
Remarks

Unity adds this USS class to every instance of the GridView element. Any styling applied to this class affects every GridView located beside, or below the stylesheet in the visual tree.

Properties

allowNoSelection

Whether the GridView allows to have no selection when the selection type is Single or Multiple.

Declaration
public bool allowNoSelection { get; set; }
Property Value
Type Description
bool

bindItem

Callback for binding a data item to the visual element.

Declaration
public Action<VisualElement, int> bindItem { get; set; }
Property Value
Type Description
Action<VisualElement, int>
Remarks

The method called by this callback receives the VisualElement to bind, and the index of the element to bind it to.

columnCount

The number of columns for this grid.

Declaration
public int columnCount { get; set; }
Property Value
Type Description
int

contentContainer

Returns the content container for the GridView. Because the GridView control automatically manages its content, this always returns null.

Declaration
public override VisualElement contentContainer { get; }
Property Value
Type Description
VisualElement
Overrides

dragger

The Dragger manipulator used by this GridView.

Declaration
public Dragger dragger { get; }
Property Value
Type Description
Dragger

getItemId

Callback for getting the ID of an item.

Declaration
public Func<int, int> getItemId { get; set; }
Property Value
Type Description
Func<int, int>
Remarks

The method called by this callback receives the index of the item to get the ID from.

isSelecting

Returns true if the soft-selection is in progress.

Declaration
public bool isSelecting { get; }
Property Value
Type Description
bool

itemHeight

The height of a single item in the list, in pixels.

Declaration
public int itemHeight { get; set; }
Property Value
Type Description
int
Remarks

GridView requires that all visual elements have the same height so that it can calculate the scroller size.

This property must be set for the list view to function.

itemWidth

The width of a single item in the list, in logical pixels.

Declaration
public float itemWidth { get; }
Property Value
Type Description
float

itemsSource

The data source for list items.

Declaration
public IList itemsSource { get; set; }
Property Value
Type Description
IList
Remarks

This list contains the items that the GridView displays.

This property must be set for the list view to function.

makeItem

Callback for constructing the VisualElement that is the template for each recycled and re-bound element in the list.

Declaration
public Func<VisualElement> makeItem { get; set; }
Property Value
Type Description
Func<VisualElement>
Remarks

This callback needs to call a function that constructs a blank VisualElement that is bound to an element from the list.

The GridView automatically creates enough elements to fill the visible area, and adds more if the area is expanded. As the user scrolls, the GridView cycles elements in and out as they appear or disappear.

This property must be set for the list view to function.

operationMask

A mask describing available operations in this GridView when the user interacts with it.

Declaration
public GridView.GridOperations operationMask { get; set; }
Property Value
Type Description
GridView.GridOperations

preventScrollWithModifiers

Prevents the grid view from scrolling when the user presses a modifier key at the same time as scrolling.

Declaration
public bool preventScrollWithModifiers { get; set; }
Property Value
Type Description
bool

resolvedItemHeight

The computed pixel-aligned height for the list elements.

Declaration
public float resolvedItemHeight { get; }
Property Value
Type Description
float
Remarks

This value changes depending on the current panel's DPI scaling.

See Also

resolvedItemWidth

The rounded value of item width in logical pixels using the current panel's scale factor.

Declaration
public float resolvedItemWidth { get; }
Property Value
Type Description
float

scrollView

The ScrollView used by the GridView.

Declaration
public ScrollView scrollView { get; }
Property Value
Type Description
ScrollView

selectedIds

Returns the IDs of selected items in the data source. Always returns an enumerable, even if no item is selected, or a single item is selected.

Declaration
public IEnumerable<int> selectedIds { get; }
Property Value
Type Description
IEnumerable<int>

selectedIndex

Returns or sets the selected item's index in the data source. If multiple items are selected, returns the first selected item's index. If multiple items are provided, sets them all as selected.

Declaration
public int selectedIndex { get; set; }
Property Value
Type Description
int

selectedIndices

Returns the indices of selected items in the data source. Always returns an enumerable, even if no item is selected, or a single item is selected.

Declaration
public IEnumerable<int> selectedIndices { get; }
Property Value
Type Description
IEnumerable<int>

selectedItem

Returns the selected item from the data source. If multiple items are selected, returns the first selected item.

Declaration
public object selectedItem { get; }
Property Value
Type Description
object

selectedItems

Returns the selected items from the data source. Always returns an enumerable, even if no item is selected, or a single item is selected.

Declaration
public IEnumerable<object> selectedItems { get; }
Property Value
Type Description
IEnumerable<object>

selectionType

Controls the selection type.

Declaration
public SelectionType selectionType { get; set; }
Property Value
Type Description
SelectionType
Remarks

You can set the GridView to make one item selectable at a time, make multiple items selectable, or disable selections completely.

When you set the GridView to disable selections, any current selection is cleared.

showBorder

Enable this property to display a border around the GridView.

Declaration
public bool showBorder { get; set; }
Property Value
Type Description
bool
Remarks

If set to true, a border appears around the ScrollView.

unbindItem

Callback for unbinding a data item from the VisualElement.

Declaration
public Action<VisualElement, int> unbindItem { get; set; }
Property Value
Type Description
Action<VisualElement, int>
Remarks

The method called by this callback receives the VisualElement to unbind, and the index of the element to unbind it from.

Methods

AddToSelection(int)

Adds an item to the collection of selected items.

Declaration
public void AddToSelection(int index)
Parameters
Type Name Description
int index

Item index.

CancelDrag()

Cancel drag operation.

Declaration
public void CancelDrag()

ClearSelection()

Deselects any selected items.

Declaration
public void ClearSelection()

ClearSelectionWithoutNotify()

Clear the selection without triggering selection changed event.

Declaration
public void ClearSelectionWithoutNotify()

GetIndexByWorldPosition(Vector2)

Returns the index of the item at the given position.

Declaration
public int GetIndexByWorldPosition(Vector2 worldPosition)
Parameters
Type Name Description
Vector2 worldPosition

The position of the item in the world-space.
Returns
Type Description
int

The index of the item at the given position.
Remarks

The position is relative to the top left corner of the grid. No check is made to see if the index is valid.

Refresh()

Clears the GridView, recreates all visible visual elements, and rebinds all items.

Declaration
public void Refresh()
Remarks

Call this method whenever the data source changes.

RemoveFromSelection(int)

Removes an item from the collection of selected items.

Declaration
public void RemoveFromSelection(int index)
Parameters
Type Name Description
int index

The item index.

ScrollToItem(int)

Scrolls to a specific item index and makes it visible.

Declaration
public void ScrollToItem(int index)
Parameters
Type Name Description
int index

Item index to scroll to. Specify -1 to make the last item visible.

SetSelection(IEnumerable<int>)

Sets a collection of selected items.

Declaration
public void SetSelection(IEnumerable<int> indices)
Parameters
Type Name Description
IEnumerable<int> indices

The collection of the indices of the items to be selected.

SetSelection(int)

Sets the currently selected item.

Declaration
public void SetSelection(int index)
Parameters
Type Name Description
int index

The item index.

SetSelectionWithoutNotify(IEnumerable<int>)

Sets a collection of selected items without triggering a selection change callback.

Declaration
public void SetSelectionWithoutNotify(IEnumerable<int> indices)
Parameters
Type Name Description
IEnumerable<int> indices

The collection of items to be selected.

Events

contextClicked

Callback triggered when the user right-clicks on an item.

Declaration
public event Action<PointerDownEvent> contextClicked
Event Type
Type Description
Action<PointerDownEvent>
Remarks

This callback receives an enumerable that contains the item or items selected.

doubleClicked

Callback triggered when the user double-clicks on an item.

Declaration
public event Action<int> doubleClicked
Event Type
Type Description
Action<int>

dragCanceled

Callback triggered when drag has been canceled.

Declaration
public event Action dragCanceled
Event Type
Type Description
Action

dragFinished

Callback triggered when drag has finished.

Declaration
public event Action<PointerUpEvent> dragFinished
Event Type
Type Description
Action<PointerUpEvent>

dragStarted

Callback triggered when drag has started.

Declaration
public event Action<PointerMoveEvent> dragStarted
Event Type
Type Description
Action<PointerMoveEvent>

dragUpdated

Callback triggered when items are dragged.

Declaration
public event Action<PointerMoveEvent> dragUpdated
Event Type
Type Description
Action<PointerMoveEvent>

itemsChosen

Callback triggered when the user acts on a selection of one or more items, for example by double-clicking or pressing Enter.

Declaration
public event Action<IEnumerable<object>> itemsChosen
Event Type
Type Description
Action<IEnumerable<object>>
Remarks

This callback receives an enumerable that contains the item or items chosen.

selectedIndicesChanged

Callback triggered when the selection changes.

Declaration
public event Action<IEnumerable<int>> selectedIndicesChanged
Event Type
Type Description
Action<IEnumerable<int>>
Remarks

This callback receives an enumerable that contains the indices of selected items.

selectionChanged

Callback triggered when the selection changes.

Declaration
public event Action<IEnumerable<object>> selectionChanged
Event Type
Type Description
Action<IEnumerable<object>>
Remarks

This callback receives an enumerable that contains the item or items selected.

Implements

Extension Methods