SEyeDropperButton.h

Go to the documentation of this file.

// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "CoreMinimal.h"
#include "Misc/Attribute.h"
#include "Input/CursorReply.h"
#include "Input/Reply.h"
#include "Layout/Visibility.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Styling/SlateColor.h"
#include "Widgets/Input/SButton.h"
 
class SEyeDropperButton : public SButton
{
public:
    DECLARE_DELEGATE_OneParam(FOnDropperComplete, bool)
 
    SLATE_BEGIN_ARGS( SEyeDropperButton )
        : _OnValueChanged()
        , _OnBegin()
        , _OnComplete()
        , _DisplayGamma()
        {}
 
        SLATE_EVENT(FOnLinearColorValueChanged, OnValueChanged)
 
        
        SLATE_EVENT(FSimpleDelegate, OnBegin)
 
        
        SLATE_EVENT(FOnDropperComplete, OnComplete)
 
        
        SLATE_ATTRIBUTE(float, DisplayGamma)
 
    SLATE_END_ARGS()
 
    void Construct(const FArguments& InArgs);
 
    virtual FReply OnMouseButtonDown(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    virtual FReply OnMouseButtonUp(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    virtual FReply OnMouseMove(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) override;
    virtual FReply OnKeyDown(const FGeometry& MyGeometry, const FKeyEvent& InKeyEvent) override;
    virtual FCursorReply OnCursorQuery(const FGeometry& MyGeometry, const FPointerEvent& CursorEvent) const override;
    virtual void OnMouseCaptureLost(const FCaptureLostEvent& CaptureLostEvent) override;
 
private:
 
    FReply OnClicked();
 
    EVisibility GetEscapeTextVisibility() const;
 
    FSlateColor GetDropperImageColor() const;
 
    bool IsMouseOver(const FGeometry& MyGeometry, const FPointerEvent& MouseEvent) const;
 
    void OnPreTick(float DeltaTime);
    void ResetDropperModeStates();
 
private:
 
    FOnLinearColorValueChanged OnValueChanged;
 
    FSimpleDelegate OnBegin;
 
    FOnDropperComplete OnComplete;
 
    TAttribute<float> DisplayGamma;
 
    TOptional<FVector2D> LastCursorPosition;
 
    // Dropper states
    bool bWasClicked;
    bool bWasClickActivated;
    bool bWasLeft;
    bool bWasReEntered;
};