Files
UnrealEngine/Engine/Source/Runtime/UMG/Public/Components/CanvasPanel.h
2025-05-18 13:04:45 +08:00

76 lines
2.3 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#pragma once
#include "CoreMinimal.h"
#include "UObject/ObjectMacros.h"
#include "Widgets/SWidget.h"
#include "Widgets/Layout/SConstraintCanvas.h"
#include "Components/PanelWidget.h"
#include "CanvasPanel.generated.h"
class UCanvasPanelSlot;
/**
* The canvas panel is a designer friendly panel that allows widgets to be laid out at arbitrary
* locations, anchored and z-ordered with other children of the canvas. The canvas is a great widget
* for manual layout, but bad when you want to procedurally just generate widgets and place them in a
* container (unless you want absolute layout).
*
* * Many Children
* * Absolute Layout
* * Anchors
*/
UCLASS(meta = (ShortTooltip = "A designer-friendly panel useful for laying out top-level widgets. Use sparingly."), MinimalAPI)
class UCanvasPanel : public UPanelWidget
{
GENERATED_UCLASS_BODY()
public:
/** */
UFUNCTION(BlueprintCallable, Category="Canvas Panel")
UMG_API UCanvasPanelSlot* AddChildToCanvas(UWidget* Content);
/** Gets the underlying native canvas widget if it has been constructed */
UMG_API TSharedPtr<class SConstraintCanvas> GetCanvasWidget() const;
/** Computes the geometry for a particular slot based on the current geometry of the canvas. */
UMG_API bool GetGeometryForSlot(int32 SlotIndex, FGeometry& ArrangedGeometry) const;
/** Computes the geometry for a particular slot based on the current geometry of the canvas. */
UMG_API bool GetGeometryForSlot(UCanvasPanelSlot* Slot, FGeometry& ArrangedGeometry) const;
UMG_API void ReleaseSlateResources(bool bReleaseChildren) override;
#if WITH_EDITOR
// UWidget interface
UMG_API virtual const FText GetPaletteCategory() override;
// End UWidget interface
// UWidget interface
virtual bool LockToPanelOnDrag() const override
{
return true;
}
// End UWidget interface
#endif
protected:
// UPanelWidget
UMG_API virtual UClass* GetSlotClass() const override;
UMG_API virtual void OnSlotAdded(UPanelSlot* Slot) override;
UMG_API virtual void OnSlotRemoved(UPanelSlot* Slot) override;
// End UPanelWidget
protected:
TSharedPtr<class SConstraintCanvas> MyCanvas;
protected:
// UWidget interface
UMG_API virtual TSharedRef<SWidget> RebuildWidget() override;
// End of UWidget interface
};