| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package android.transition; |
| |
| import android.view.ViewGroup; |
| |
| /** |
| * Extend <code>TransitionPropagation</code> to customize start delays for Animators created |
| * in {@link android.transition.Transition#createAnimator(ViewGroup, |
| * TransitionValues, TransitionValues)}. A Transition such as {@link android.transition.Explode} |
| * defaults to using {@link android.transition.CircularPropagation} and Views closer to the |
| * epicenter will move out of the scene later and into the scene sooner than Views farther |
| * from the epicenter, giving the appearance of inertia. With no TransitionPropagation, all |
| * Views will react simultaneously to the start of the transition. |
| * |
| * @see Transition#setPropagation(TransitionPropagation) |
| * @see Transition#getEpicenter() |
| */ |
| public abstract class TransitionPropagation { |
| /** |
| * Called by Transition to alter the Animator start delay. All start delays will be adjusted |
| * such that the minimum becomes zero. |
| * @param sceneRoot The root of the View hierarchy running the transition. |
| * @param transition The transition that created the Animator |
| * @param startValues The values for a specific target in the start scene. |
| * @param endValues The values for the target in the end scene. |
| * @return A start delay to use with the Animator created by <code>transition</code>. The |
| * delay will be offset by the minimum delay of all <code>TransitionPropagation</code>s |
| * used in the Transition so that the smallest delay will be 0. Returned values may be |
| * negative. |
| */ |
| public abstract long getStartDelay(ViewGroup sceneRoot, Transition transition, |
| TransitionValues startValues, TransitionValues endValues); |
| |
| /** |
| * Captures the values in the start or end scene for the properties that this |
| * transition propagation monitors. These values are then passed as the startValues |
| * or endValues structure in a later call to |
| * {@link #getStartDelay(ViewGroup, Transition, 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 |
| * {@link #getStartDelay(ViewGroup, Transition, TransitionValues, TransitionValues)}. |
| * method to determine the start delay. |
| * |
| * <p>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.</p> |
| * |
| * @param transitionValues The holder for any values that the Transition |
| * wishes to store. Values are stored in the <code>values</code> 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 |
| * <code>transitionValues.values.put("appname:transitionname:rotation", |
| * view.getRotation())</code>. The target view will already be stored in |
| * the transitionValues structure when this method is called. |
| */ |
| public abstract void captureValues(TransitionValues transitionValues); |
| |
| /** |
| * Returns the set of property names stored in the {@link TransitionValues} |
| * object passed into {@link #captureValues(TransitionValues)} that |
| * this transition propagation cares about for the purposes of preventing |
| * duplicate capturing of property values. |
| |
| * <p>A <code>TransitionPropagation</code> must override this method to prevent |
| * duplicate capturing of values and must contain at least one </p> |
| * |
| * @return An array of property names as described in the class documentation for |
| * {@link TransitionValues}. |
| */ |
| public abstract String[] getPropagationProperties() ; |
| } |