ezEngine  Release 25.03
Static Public Member Functions | Protected Member Functions | List of all members
ezDragDropHandler Class Referenceabstract
Inheritance diagram for ezDragDropHandler:
Inheritance graph
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Static Public Member Functions

static bool IsHandlerActive ()
 Returns whether the last call to BeginDragDropOperation() was successful and a handler is now in effect.
 
static bool BeginDragDropOperation (const ezDragDropInfo *pInfo, ezDragDropConfig *pConfigToFillOut=nullptr)
 Call this when a drag enter event occurs. Return value indicates whether a ezDragDropHandler was found to handle the operation. If not, subsequent drag & drop updates are ignored.
 
static void UpdateDragDropOperation (const ezDragDropInfo *pInfo)
 Call this when a drag event occurs. Ignored if BeginDragDropOperation() was not successful.
 
static void FinishDragDrop (const ezDragDropInfo *pInfo)
 Call this when a drop event occurs. Ignored if BeginDragDropOperation() was not successful.
 
static void CancelDragDrop ()
 Call this when a drag leave event occurs. Ignored if BeginDragDropOperation() was not successful.
 
static bool CanDropOnly (const ezDragDropInfo *pInfo)
 For targets that do not support full dragging, but only dropping on a single target, this allows to query whether there is a handler for the given target. See also DropOnly().
 
static bool DropOnly (const ezDragDropInfo *pInfo)
 Executes a complete drop action on a target that does not support continuous dragging. See also CanDropOnly().
 
- Static Public Member Functions inherited from ezNoBase
static const ezRTTI * GetStaticRTTI ()
 

Protected Member Functions

virtual float CanHandle (const ezDragDropInfo *pInfo) const =0
 Used to ask a handler whether it knows how to handle a certain drag & drop situation. More...
 
virtual void RequestConfiguration (ezDragDropConfig *pConfigToFillOut)
 Potentially called by the drag drop target to request information about how to determine the ezDragDropInfo data.
 
virtual void OnDragBegin (const ezDragDropInfo *pInfo)=0
 Called shortly after CanHandle returned true to begin handling a drag operation.
 
virtual void OnDragUpdate (const ezDragDropInfo *pInfo)=0
 Called to update the drag operation with the latest state.
 
virtual void OnDragCancel ()=0
 Called when the drag operation leaves the designated area. The handler will be destroyed after this. It should clean up all temporary objects that it created before.
 
virtual void OnDrop (const ezDragDropInfo *pInfo)=0
 Final call to finish the drag & drop operation. Handler is destroyed after this.
 

Additional Inherited Members

- Public Member Functions inherited from ezReflectedClass
virtual const ezRTTI * GetDynamicRTTI () const
 
bool IsInstanceOf (const ezRTTI *pType) const
 Returns whether the type of this instance is of the given type or derived from it.
 
template<typename T >
EZ_ALWAYS_INLINE bool IsInstanceOf () const
 Returns whether the type of this instance is of the given type or derived from it.
 

Member Function Documentation

◆ CanHandle()

virtual float ezDragDropHandler::CanHandle ( const ezDragDropInfo *  pInfo) const
protectedpure virtual

Used to ask a handler whether it knows how to handle a certain drag & drop situation.

The return value is a priority. By default CanHandle should return 0 or 1. To override an existing handler, values larger than 1 may be returned to take precedence.

Implemented in ezComponentDragDropHandler, ezGameObjectOnLayerDragDropHandler, ezLayerOnLayerDragDropHandler, ezAnimatedMeshComponentDragDropHandler, ezMaterialDragDropHandler, ezProcPlacementComponentDragDropHandler, ezSoundEventComponentDragDropHandler, ezJoltCollisionMeshComponentDragDropHandler, ezKrautTreeComponentDragDropHandler, ezParticleComponentDragDropHandler, ezCollisionMeshComponentDragDropHandler, ezRmlUiComponentDragDropHandler, ezDecalComponentDragDropHandler, ezMeshComponentDragDropHandler, ezPrefabComponentDragDropHandler, ezSkeletonComponentDragDropHandler, ezTypeScriptComponentDragDropHandler, and ezVisualScriptComponentDragDropHandler.

The documentation for this class was generated from the following files: