public abstract class Visibility extends Transition
View.setVisibility(int)
state of views, but also whether
views exist in the current view hierarchy. The class is intended to be a
utility for subclasses such as Fade
, which use this visibility
information to determine the specific animations to run when visibility
changes occur. Subclasses should implement one or both of the methods
onAppear(ViewGroup, TransitionValues, int, TransitionValues, int)
,
onDisappear(ViewGroup, TransitionValues, int, TransitionValues, int)
or
onAppear(ViewGroup, View, TransitionValues, TransitionValues)
,
onDisappear(ViewGroup, View, TransitionValues, TransitionValues)
.Transition.AnimationInfo, Transition.EpicenterCallback, Transition.TransitionListener, Transition.TransitionListenerAdapter
Modifier and Type | Field and Description |
---|---|
static int |
MODE_IN
Mode used in
setMode(int) to make the transition
operate on targets that are appearing. |
static int |
MODE_OUT
Mode used in
setMode(int) to make the transition
operate on targets that are disappearing. |
MATCH_ID, MATCH_INSTANCE, MATCH_ITEM_ID, MATCH_NAME
Constructor and Description |
---|
Visibility() |
Visibility(Context context,
AttributeSet attrs) |
Modifier and Type | Method and Description |
---|---|
void |
captureEndValues(TransitionValues transitionValues)
Captures the values in the end scene for the properties that this
transition monitors.
|
void |
captureStartValues(TransitionValues transitionValues)
Captures the values in the start scene for the properties that this
transition monitors.
|
Animator |
createAnimator(ViewGroup sceneRoot,
TransitionValues startValues,
TransitionValues endValues)
This method creates an animation that will be run for this transition
given the information in the startValues and endValues structures captured
earlier for the start and end scenes.
|
int |
getMode()
Returns whether appearing and/or disappearing Views are supported.
|
String[] |
getTransitionProperties()
Returns the set of property names used stored in the
TransitionValues
object passed into Transition.captureStartValues(TransitionValues) that
this transition cares about for the purposes of canceling overlapping animations. |
boolean |
isTransitionRequired(TransitionValues startValues,
TransitionValues newValues)
Returns whether or not the transition should create an Animator, based on the values
captured during
Transition.captureStartValues(TransitionValues) and
Transition.captureEndValues(TransitionValues) . |
boolean |
isVisible(TransitionValues values)
Returns whether the view is 'visible' according to the given values
object.
|
Animator |
onAppear(ViewGroup sceneRoot,
TransitionValues startValues,
int startVisibility,
TransitionValues endValues,
int endVisibility)
The default implementation of this method calls
onAppear(ViewGroup, View, TransitionValues, TransitionValues) . |
Animator |
onAppear(ViewGroup sceneRoot,
View view,
TransitionValues startValues,
TransitionValues endValues)
The default implementation of this method returns a null Animator.
|
Animator |
onDisappear(ViewGroup sceneRoot,
TransitionValues startValues,
int startVisibility,
TransitionValues endValues,
int endVisibility)
Subclasses should override this method or
onDisappear(ViewGroup, View, TransitionValues, TransitionValues)
if they need to create an Animator when targets disappear. |
Animator |
onDisappear(ViewGroup sceneRoot,
View view,
TransitionValues startValues,
TransitionValues endValues)
The default implementation of this method returns a null Animator.
|
void |
setMode(int mode)
Changes the transition to support appearing and/or disappearing Views, depending
on
mode . |
void |
setSuppressLayout(boolean suppress)
This tells the Visibility transition to suppress layout during the transition and release
the suppression after the transition.
|
addListener, addTarget, addTarget, addTarget, addTarget, animate, cancel, canRemoveViews, clone, createAnimators, end, excludeChildren, excludeChildren, excludeChildren, excludeTarget, excludeTarget, excludeTarget, excludeTarget, getDuration, getEpicenter, getEpicenterCallback, getInterpolator, getName, getNameOverrides, getPathMotion, getPropagation, getStartDelay, getTargetIds, getTargetNames, getTargets, getTargetTypes, getTargetViewNames, getTransitionValues, pause, removeListener, removeTarget, removeTarget, removeTarget, removeTarget, resume, runAnimators, setDuration, setEpicenterCallback, setInterpolator, setMatchOrder, setNameOverrides, setPathMotion, setPropagation, setStartDelay, start, toString
public static final int MODE_IN
setMode(int)
to make the transition
operate on targets that are appearing. Maybe be combined with
MODE_OUT
to target Visibility changes both in and out.public static final int MODE_OUT
setMode(int)
to make the transition
operate on targets that are disappearing. Maybe be combined with
MODE_IN
to target Visibility changes both in and out.public Visibility()
public Visibility(Context context, AttributeSet attrs)
public void setSuppressLayout(boolean suppress)
public void setMode(int mode)
mode
.public int getMode()
public String[] getTransitionProperties()
Transition
TransitionValues
object passed into Transition.captureStartValues(TransitionValues)
that
this transition cares about for the purposes of canceling overlapping animations.
When any transition is started on a given scene root, all transitions
currently running on that same scene root are checked to see whether the
properties on which they based their animations agree with the end values of
the same properties in the new transition. If the end values are not equal,
then the old animation is canceled since the new transition will start a new
animation to these new values. If the values are equal, the old animation is
allowed to continue and no new animation is started for that transition.
A transition does not need to override this method. However, not doing so will mean that the cancellation logic outlined in the previous paragraph will be skipped for that transition, possibly leading to artifacts as old transitions and new transitions on the same targets run in parallel, animating views toward potentially different end values.
getTransitionProperties
in class Transition
TransitionValues
. The default implementation returns null
.public void captureStartValues(TransitionValues transitionValues)
Transition
Transition.createAnimator(ViewGroup, TransitionValues, TransitionValues)
.
The main concern for an implementation is what the
properties are that the transition cares about and what the values are
for all of those properties. The start and end values will be compared
later during the
Transition.createAnimator(android.view.ViewGroup, TransitionValues, TransitionValues)
method to determine what, if any, animations, should be run.
Subclasses must implement this method. The method should only be called by the transition system; it is not intended to be called from external classes.
captureStartValues
in class Transition
transitionValues
- The holder for any values that the Transition
wishes to store. Values are stored in the values
field
of this TransitionValues object and are keyed from
a String value. For example, to store a view's rotation value,
a transition might call
transitionValues.values.put("appname:transitionname:rotation",
view.getRotation())
. The target view will already be stored in
the transitionValues structure when this method is called.Transition.captureEndValues(TransitionValues)
,
Transition.createAnimator(ViewGroup, TransitionValues, TransitionValues)
public void captureEndValues(TransitionValues transitionValues)
Transition
Transition.createAnimator(ViewGroup, TransitionValues, TransitionValues)
.
The main concern for an implementation is what the
properties are that the transition cares about and what the values are
for all of those properties. The start and end values will be compared
later during the
Transition.createAnimator(android.view.ViewGroup, TransitionValues, TransitionValues)
method to determine what, if any, animations, should be run.
Subclasses must implement this method. The method should only be called by the transition system; it is not intended to be called from external classes.
captureEndValues
in class Transition
transitionValues
- The holder for any values that the Transition
wishes to store. Values are stored in the values
field
of this TransitionValues object and are keyed from
a String value. For example, to store a view's rotation value,
a transition might call
transitionValues.values.put("appname:transitionname:rotation",
view.getRotation())
. The target view will already be stored in
the transitionValues structure when this method is called.Transition.captureStartValues(TransitionValues)
,
Transition.createAnimator(ViewGroup, TransitionValues, TransitionValues)
public boolean isVisible(TransitionValues values)
Transition.createAnimator(ViewGroup, TransitionValues, TransitionValues)
method. This method can be called by, for example, subclasses that want
to know whether the object is visible in the same way that Visibility
determines it for the actual animation.values
- The TransitionValues object that holds the information by
which visibility is determined.values
is visible,
false otherwise.public Animator createAnimator(ViewGroup sceneRoot, TransitionValues startValues, TransitionValues endValues)
Transition
This method is called by the transition's parent (all the way up to the
topmost Transition in the hierarchy) with the sceneRoot and start/end
values that the transition may need to set up initial target values
and construct an appropriate animation. For example, if an overall
Transition is a TransitionSet
consisting of several
child transitions in sequence, then some of the child transitions may
want to set initial values on target views prior to the overall
Transition commencing, to put them in an appropriate state for the
delay between that start and the child Transition start time. For
example, a transition that fades an item in may wish to set the starting
alpha value to 0, to avoid it blinking in prior to the transition
actually starting the animation. This is necessary because the scene
change that triggers the Transition will automatically set the end-scene
on all target views, so a Transition that wants to animate from a
different value should set that value prior to returning from this method.
Additionally, a Transition can perform logic to determine whether the transition needs to run on the given target and start/end values. For example, a transition that resizes objects on the screen may wish to avoid running for views which are not present in either the start or end scenes.
If there is an animator created and returned from this method, the
transition mechanism will apply any applicable duration, startDelay,
and interpolator to that animation and start it. A return value of
null
indicates that no animation should run. The default
implementation returns null.
The method is called for every applicable target object, which is
stored in the TransitionValues.view
field.
createAnimator
in class Transition
sceneRoot
- The root of the transition hierarchy.startValues
- The values for a specific target in the start scene.endValues
- The values for the target in the end scene.public Animator onAppear(ViewGroup sceneRoot, TransitionValues startValues, int startVisibility, TransitionValues endValues, int endVisibility)
onAppear(ViewGroup, View, TransitionValues, TransitionValues)
.
Subclasses should override this method or
onAppear(ViewGroup, View, TransitionValues, TransitionValues)
.
if they need to create an Animator when targets appear.
The method should only be called by the Visibility class; it is
not intended to be called from external classes.sceneRoot
- The root of the transition hierarchystartValues
- The target values in the start scenestartVisibility
- The target visibility in the start sceneendValues
- The target values in the end sceneendVisibility
- The target visibility in the end scenepublic Animator onAppear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues)
onAppear(ViewGroup, TransitionValues, int, TransitionValues, int)
.sceneRoot
- The root of the transition hierarchyview
- The View to make appear. This will be in the target scene's View hierarchy and
will be VISIBLE.startValues
- The target values in the start sceneendValues
- The target values in the end scenepublic Animator onDisappear(ViewGroup sceneRoot, TransitionValues startValues, int startVisibility, TransitionValues endValues, int endVisibility)
onDisappear(ViewGroup, View, TransitionValues, TransitionValues)
if they need to create an Animator when targets disappear.
The method should only be called by the Visibility class; it is
not intended to be called from external classes.
The default implementation of this method attempts to find a View to use to call
onDisappear(ViewGroup, View, TransitionValues, TransitionValues)
,
based on the situation of the View in the View hierarchy. For example,
if a View was simply removed from its parent, then the View will be added
into a ViewGroupOverlay
and passed as the view
parameter in onDisappear(ViewGroup, View, TransitionValues, TransitionValues)
.
If a visible View is changed to be View.GONE
or View.INVISIBLE
,
then it can be used as the view
and the visibility will be changed
to View.VISIBLE
for the duration of the animation. However, if a View
is in a hierarchy which is also altering its visibility, the situation can be
more complicated. In general, if a view that is no longer in the hierarchy in
the end scene still has a parent (so its parent hierarchy was removed, but it
was not removed from its parent), then it will be left alone to avoid side-effects from
improperly removing it from its parent. The only exception to this is if
the previous Scene
was created from a layout resource file
, then it is considered
safe to un-parent the starting scene view in order to make it disappear.
sceneRoot
- The root of the transition hierarchystartValues
- The target values in the start scenestartVisibility
- The target visibility in the start sceneendValues
- The target values in the end sceneendVisibility
- The target visibility in the end scenepublic boolean isTransitionRequired(TransitionValues startValues, TransitionValues newValues)
Transition
Transition.captureStartValues(TransitionValues)
and
Transition.captureEndValues(TransitionValues)
. The default implementation compares the
property values returned from Transition.getTransitionProperties()
, or all property values if
getTransitionProperties()
returns null. Subclasses may override this method to
provide logic more specific to the transition implementation.isTransitionRequired
in class Transition
startValues
- the values from captureStartValues, This may be null
if the
View did not exist in the start state.newValues
- the values from captureEndValues. This may be null
if the View
did not exist in the end state.public Animator onDisappear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues)
onDisappear(ViewGroup, TransitionValues, int, TransitionValues, int)
.sceneRoot
- The root of the transition hierarchyview
- The View to make disappear. This will be in the target scene's View
hierarchy or in an ViewGroupOverlay
and will be
VISIBLE.startValues
- The target values in the start sceneendValues
- The target values in the end scene