private void StopDrag(IPropHolder widget, DragCtx ctx)
{
if (!ctx.IsDragging)
{
return;
}
ctx.IsDragging = false;
widget.Props.RemoveSingleProp(_onUpdateDrag !);
}
private void StartDrag(IPropHolder widget, bool isXFixed, bool isYFixed, DragCtx dragCtx)
{
if (isXFixed && isYFixed)
{
return;
}
var devLoc = _device.GetPointedLocation();
if (dragCtx.IsDragging)
{
return;
}
dragCtx.IsDragging = true;
dragCtx.Set(devLoc);
widget.WithProp(_onUpdateDrag !);
}
private void Dragging(IWidget widget, bool isXFixed, bool isYFixed, DragCtx dragCtx)
{
var devLoc = _device.GetPointedLocation();
var devX = devLoc.X;
var devY = devLoc.Y;
var(x, y, w, h) = widget.Space;
if (Math.Abs(dragCtx.DevX - devX) < 0.01f && Math.Abs(dragCtx.DevY - devY) < 0.01f)
{
return;
}
var nx = x + (isXFixed ? 0 : devX - dragCtx.DevX);
var ny = y + (isYFixed ? 0 : devY - dragCtx.DevY);
(nx, ny) = CheckBounds(widget, nx, ny, isXFixed, isYFixed);
WidgetsSpaceHelper.UpdateSpace(widget, new RectangleF(nx, ny, w, h));
dragCtx.Set(devLoc);
}
/// <summary>
/// Adds an OnPress and OnRelease actions to the widget that handle the dragging logic.
/// </summary>
/// <param name="widget"></param>
public void ApplyOn(IWidget widget)
{
ApplicationDone = false;
var dragCtx = new DragCtx();
var foundFixX = widget.Props.SafeGetByProp <FixX>().TryGetValue(out var fixX);
var foundFixY = widget.Props.SafeGetByProp <FixY>().TryGetValue(out var fixY);
bool isXFixed = foundFixX && fixX.Count > 0;
bool isYFixed = foundFixY && fixY.Count > 0;
OnPress onPress = new OnPress(() => StartDrag(widget, isXFixed, isYFixed, dragCtx));
OnRelease onRelease = new OnRelease(() => StopDrag(widget, dragCtx));
OnExit onExit = new OnExit(() => StopDrag(widget, dragCtx));
widget.WithProp(onPress);
widget.WithProp(onRelease);
widget.WithProp(onExit);
_onUpdateDrag = new OnUpdate(() => Dragging(widget, isXFixed, isYFixed, dragCtx));
ApplicationDone = true;
OnApplied();
}
