urho3d/Engine/UI/Slider.h

//
// Urho3D Engine
// Copyright (c) 2008-2012 Lasse Öörni
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#pragma once

#include "BorderImage.h"

/// %Slider bar %UI element.
class Slider : public BorderImage
{
    OBJECT(Slider);
    
    using UIElement::SetStyle;
    
public:
    /// Construct.
    Slider(Context* context);
    /// Destruct.
    virtual ~Slider();
    /// Register object factory.
    static void RegisterObject(Context* context);
    
    /// %Set UI element style from XML data.
    virtual void SetStyle(const XMLElement& element);
    /// Perform UI element update.
    virtual void Update(float timeStep);
    /// React to mouse hover.
    virtual void OnHover(const IntVector2& position, const IntVector2& screenPosition, int buttons, int qualifiers, Cursor* cursor);
    /// React to mouse drag start.
    virtual void OnDragStart(const IntVector2& position, const IntVector2& screenPosition, int buttons, int qualifiers, Cursor* cursor);
    /// React to mouse drag motion.
    virtual void OnDragMove(const IntVector2& position, const IntVector2& screenPosition, int buttons, int qualifiers, Cursor* cursor);
    /// React to mouse drag end.
    virtual void OnDragEnd(const IntVector2& position, const IntVector2& screenPosition, Cursor* cursor);
    /// React to resize.
    virtual void OnResize();
    
    /// %Set orientation type.
    void SetOrientation(Orientation orientation);
    /// %Set slider range maximum value (minimum value is always 0.)
    void SetRange(float range);
    /// %Set slider current value.
    void SetValue(float value);
    /// Change value by a delta.
    void ChangeValue(float delta);
    
    /// Return orientation type.
    Orientation GetOrientation() const { return orientation_; }
    /// Return slider range.
    float GetRange() const { return range_; }
    /// Return slider current value.
    float GetValue() const { return value_; }
    /// Return knob element.
    BorderImage* GetKnob() const { return knob_; }
    
protected:
    /// Update slider knob position & size.
    void UpdateSlider();
    
    /// Slider knob.
    SharedPtr<BorderImage> knob_;
    /// Orientation.
    Orientation orientation_;
    /// Slider range.
    float range_;
    /// Slider current value.
    float value_;
    /// Internal flag of whether the slider is being dragged.
    bool dragSlider_;
    /// Original mouse cursor position at drag start.
    IntVector2 dragStartCursor_;
    /// Original slider position at drag start.
    IntVector2 dragStartPosition_;
};