public
class
ChangeImageTransform
extends Transition
java.lang.Object | ||
↳ | android.transition.Transition | |
↳ | android.transition.ChangeImageTransform |
This Transition captures an ImageView's matrix before and after the scene change and animates it during the transition.
In combination with ChangeBounds, ChangeImageTransform allows ImageViews
that change size, shape, or ImageView.ScaleType
to animate contents
smoothly.
Inherited XML attributes | |
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From
class
android.transition.Transition
|
Inherited constants |
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From
class
android.transition.Transition
|
Public constructors | |
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ChangeImageTransform()
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ChangeImageTransform(Context context, AttributeSet attrs)
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Public methods | |
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void
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captureEndValues(TransitionValues transitionValues)
Captures the values in the end scene for the properties that this transition monitors. |
void
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captureStartValues(TransitionValues transitionValues)
Captures the values in the start scene for the properties that this transition monitors. |
Animator
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createAnimator(ViewGroup sceneRoot, TransitionValues startValues, TransitionValues endValues)
Creates an Animator for ImageViews moving, changing dimensions, and/or changing
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String[]
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getTransitionProperties()
Returns the set of property names used stored in the |
Inherited methods | |
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From
class
android.transition.Transition
| |
From
class
java.lang.Object
|
ChangeImageTransform (Context context, AttributeSet attrs)
Parameters | |
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context |
Context
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attrs |
AttributeSet
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void captureEndValues (TransitionValues transitionValues)
Captures the values in the end scene for the properties that this
transition monitors. These values are then passed as the endValues
structure in a later call to
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
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.
Parameters | |
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transitionValues |
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. |
void captureStartValues (TransitionValues transitionValues)
Captures the values in the start scene for the properties that this
transition monitors. These values are then passed as the startValues
structure in a later call to
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
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.
Parameters | |
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transitionValues |
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. |
Animator createAnimator (ViewGroup sceneRoot, TransitionValues startValues, TransitionValues endValues)
Creates an Animator for ImageViews moving, changing dimensions, and/or changing
ImageView.ScaleType
.
Parameters | |
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sceneRoot |
ViewGroup :
The root of the transition hierarchy. |
startValues |
TransitionValues :
The values for a specific target in the start scene. |
endValues |
TransitionValues :
The values for the target in the end scene. |
Returns | |
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Animator |
An Animator to move an ImageView or null if the View is not an ImageView, the Drawable changed, the View is not VISIBLE, or there was no change. |
String[] getTransitionProperties ()
Returns the set of property names used stored in the TransitionValues
object passed into 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.
Returns | |
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String[] |
An array of property names as described in the class documentation for
TransitionValues . The default implementation returns null .
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