Package ej.navigation.transition

Interface TransitionContext

public interface TransitionContext

The stage on which a Transition animates a page change.

Given to Transition.run(TransitionContext, TransitionListener), it exposes the outgoing and incoming content, the content area size, and the two primitives a transition uses to render itself: positionContents(int, int, int, int) to slide the content widgets, and blendIncoming(int) to fade the incoming content in over the outgoing one. A transition registers its Animation with animate(Animation) so the navigator can snap it to completion if a new navigation interrupts it.

Both content widgets share the same content area, laid out to fill it. Coordinates passed to positionContents(int, int, int, int) are relative to the top-left of the content area.

The navigator supplies the implementation; an application consumes this interface from its Transition and is not expected to implement it.

Since:

0.2.0

Method Summary

Modifier and Type	Method	Description
void	animate(Animation animation)	Registers and starts the animation that drives this transition.
void	blendIncoming(int opacity)	Blends the incoming content over the outgoing one at the given opacity and requests a render.
int	getContentHeight()	Returns the height of the content area shared by both contents.
int	getContentWidth()	Returns the width of the content area shared by both contents.
Widget	getIncomingContent()	Returns the content of the page being entered.
Widget	getOutgoingContent()	Returns the content of the page being left, or null when there is none.
void	positionContents(int outgoingX, int outgoingY, int incomingX, int incomingY)	Positions the outgoing and incoming contents within the content area and requests a render.

Method Detail

getOutgoingContent

@Nullable
Widget getOutgoingContent()

Returns the content of the page being left, or null when there is none.

Returns:

the outgoing content, or null if there is none.

getIncomingContent

Widget getIncomingContent()

Returns the content of the page being entered.

Returns:

the incoming content.

getContentWidth

int getContentWidth()

Returns the width of the content area shared by both contents.

Returns:

the content width in pixels.

getContentHeight

int getContentHeight()

Returns the height of the content area shared by both contents.

Returns:

the content height in pixels.

positionContents

void positionContents(int outgoingX,
                      int outgoingY,
                      int incomingX,
                      int incomingY)

Positions the outgoing and incoming contents within the content area and requests a render.

Coordinates are relative to the top-left of the content area. When there is no outgoing content, its coordinates are ignored.

Parameters:

outgoingX - the x of the outgoing content.

outgoingY - the y of the outgoing content.

incomingX - the x of the incoming content.

incomingY - the y of the incoming content.

blendIncoming

void blendIncoming(int opacity)

Blends the incoming content over the outgoing one at the given opacity and requests a render.

Parameters:

opacity - the incoming content opacity, from 0 (fully transparent) to 255 (fully opaque).

animate

void animate(Animation animation)

Registers and starts the animation that drives this transition.

The navigator stops this animation if a new navigation interrupts the transition.

Parameters:

animation - the animation to run.