ChangeImageTransform
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.
Summary
Inherited XML attributes | |
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Inherited constants |
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Public constructors | |
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ChangeImageTransform() | |
ChangeImageTransform(Context context, AttributeSet attrs) |
Public methods | |
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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) Creates an Animator for ImageViews moving, changing dimensions, and/or changing |
String[] | getTransitionProperties() Returns the set of property names used stored in the |
Inherited methods | |
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Public constructors
ChangeImageTransform
public ChangeImageTransform (Context context, AttributeSet attrs)
Parameters | |
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context | Context |
attrs | AttributeSet |
Public methods
captureEndValues
public 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(android.view.ViewGroup, android.transition.TransitionValues, android.transition.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, android.transition.TransitionValues, android.transition.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. |
captureStartValues
public 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(android.view.ViewGroup, android.transition.TransitionValues, android.transition.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, android.transition.TransitionValues, android.transition.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. |
createAnimator
public 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. This value cannot be null . |
startValues | TransitionValues : The values for a specific target in the start scene. This value may be null . |
endValues | TransitionValues : The values for the target in the end scene. This value may be null . |
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. |
getTransitionProperties
public String[] getTransitionProperties ()
Returns the set of property names used stored in the TransitionValues
object passed into captureStartValues(android.transition.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 . |