DrawerControl

[Xiaoy312]

This control is a control that allows you to use swipe gesture opens another secondary view on top of primary view.
It is designed to be integrated into SplitView and by extension into NavigationView to enable gesture support. It can also be used as it is.

The contract for the control is described below:

Type	Property Name	Description
object	DrawerContent	Content to display in the drawer (secondary view)
double	DrawerDepth	Height or width (depending on the OpenDirection) of the drawer
DrawerOpenDirection enum: {Right,Left,Down,Up}	OpenDirection	Direction in which the drawer opens.
bool	IsOpen	self-explanatory
Brush	LightDismissOverlayBackground	Brush used to paint the light dismiss area. It will be animated between 0~100% opacity as the drawer closes/opens.
double?	EdgeSwipeDetectionLength	Defines the area (horizontal: width, vertical: height) that can be used to initiate the opening swipe gesture. null for from anywhere.
bool=true	IsGestureEnabled	Indicates if the gesture events will be handled

There is an extension class DrawerControlBehavior for adjusting some of above properties through attached properties when nested in another control's template. This is done because certain properties don't fit well into SplitView and NavigationView contract, like: OpenDirection, LightDismissOverlayBackground, EdgeSwipeDetectionLength, IsGestureEnabled.

Constants:

Type	Property Name	Description
double= 1.0 / 3	DragToggleThresholdRatio	Distance (based on DrawerDepth) needed to swipe open/close the drawer
double= 0.95	AnimateSnappingThresholdRatio	If the drawer is already very close (95% way there) to the snap point, then no animation is played...
TimeSpan= 150ms	AnimationDuration	...else, a flat 150ms animation is played to finish up the work

[Xiaoy312]

There are currently some limitations/issues to the control itself:

• If contained inside a ScrollViewer, the DrawerOpenDirection cannot be parallel to the ScrollViewer (but usually not an issue, as this should be a top level control)
• ios: [iOS] The Manipulation event is never triggered when there is a ScrollViewer inside uno#5385

[Xiaoy312]

Should we split EdgeSwipeDetectionLength (double?) into
UseEdgeSwipeToOpen (bool) & EdgeSwipeDetectionLength (double)?

[davidjohnoliver]

You can just use double.NaN to indicate that it's unset, it doesn't need to be nullable.