osu/osu.Game/Graphics/Containers/OsuScrollContainer.cs

76 lines
2.5 KiB
C#

// Copyright (c) 2007-2018 ppy Pty Ltd <contact@ppy.sh>.
// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
using osu.Framework.Graphics.Containers;
using osu.Framework.Input;
using OpenTK.Input;
namespace osu.Game.Graphics.Containers
{
public class OsuScrollContainer : ScrollContainer
{
/// <summary>
/// Allows controlling the scroll bar from any position in the container using the right mouse button.
/// Uses the value of <see cref="DistanceDecayOnRightMouseScrollbar"/> to smoothly scroll to the dragged location.
/// </summary>
public bool RightMouseScrollbar = false;
/// <summary>
/// Controls the rate with which the target position is approached when performing a relative drag. Default is 0.02.
/// </summary>
public double DistanceDecayOnRightMouseScrollbar = 0.02;
private bool shouldPerformRightMouseScroll(InputState state) => RightMouseScrollbar && state.Mouse.IsPressed(MouseButton.Right);
private void scrollToRelative(float value) => ScrollTo(Clamp((value - Scrollbar.DrawSize[ScrollDim] / 2) / Scrollbar.Size[ScrollDim]), true, DistanceDecayOnRightMouseScrollbar);
private bool mouseScrollBarDragging;
protected override bool IsDragging => base.IsDragging || mouseScrollBarDragging;
protected override bool OnMouseDown(InputState state, MouseDownEventArgs args)
{
if (shouldPerformRightMouseScroll(state))
{
scrollToRelative(state.Mouse.Position[ScrollDim]);
return true;
}
return base.OnMouseDown(state, args);
}
protected override bool OnDrag(InputState state)
{
if (mouseScrollBarDragging)
{
scrollToRelative(state.Mouse.Position[ScrollDim]);
return true;
}
return base.OnDrag(state);
}
protected override bool OnDragStart(InputState state)
{
if (shouldPerformRightMouseScroll(state))
{
mouseScrollBarDragging = true;
return true;
}
return base.OnDragStart(state);
}
protected override bool OnDragEnd(InputState state)
{
if (mouseScrollBarDragging)
{
mouseScrollBarDragging = false;
return true;
}
return base.OnDragEnd(state);
}
}
}