Java tutorial
/* * Copyright (C) 2013 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 com.givewaygames.transition; import android.content.Context; import android.content.res.Resources; import android.content.res.TypedArray; import android.content.res.XmlResourceParser; import android.support.v4.util.ArrayMap; import android.util.AttributeSet; import android.util.SparseArray; import android.util.Xml; import android.view.InflateException; import android.view.ViewGroup; import android.view.animation.AnimationUtils; import org.xmlpull.v1.XmlPullParser; import org.xmlpull.v1.XmlPullParserException; import java.io.IOException; import java.util.ArrayList; /** * This class inflates scenes and transitions from resource files. * * Information on XML resource descriptions for transitions can be found for * {@link R.styleable#Transition}, {@link R.styleable#TransitionSet}, * {@link R.styleable#TransitionTarget}, {@link R.styleable#Fade}, * and {@link R.styleable#TransitionManager}. */ public class TransitionInflater { // We only need one inflater for any given context. Also, this allows us to associate // ids with unique instances per-Context, used to avoid re-inflating // already-inflated resources into new/different instances private static final ArrayMap<Context, TransitionInflater> sInflaterMap = new ArrayMap<Context, TransitionInflater>(); private Context mContext; // TODO: do we need id maps for transitions and transitionMgrs as well? SparseArray<Scene> mScenes = new SparseArray<Scene>(); private TransitionInflater(Context context) { mContext = context; } /** * Obtains the TransitionInflater from the given context. */ public static TransitionInflater from(Context context) { TransitionInflater inflater = sInflaterMap.get(context); if (inflater != null) { return inflater; } inflater = new TransitionInflater(context); sInflaterMap.put(context, inflater); return inflater; } /** * Loads a {@link Transition} object from a resource * * @param resource The resource id of the transition to load * @return The loaded Transition object * @throws android.content.res.Resources.NotFoundException when the * transition cannot be loaded */ public Transition inflateTransition(int resource) { XmlResourceParser parser = mContext.getResources().getXml(resource); try { return createTransitionFromXml(parser, Xml.asAttributeSet(parser), null); } catch (XmlPullParserException e) { InflateException ex = new InflateException(e.getMessage()); ex.initCause(e); throw ex; } catch (IOException e) { InflateException ex = new InflateException(parser.getPositionDescription() + ": " + e.getMessage()); ex.initCause(e); throw ex; } finally { parser.close(); } } /** * Loads a {@link TransitionManager} object from a resource * * * * @param resource The resource id of the transition manager to load * @return The loaded TransitionManager object * @throws android.content.res.Resources.NotFoundException when the * transition manager cannot be loaded */ public TransitionManager inflateTransitionManager(int resource, ViewGroup sceneRoot) { XmlResourceParser parser = mContext.getResources().getXml(resource); try { return createTransitionManagerFromXml(parser, Xml.asAttributeSet(parser), sceneRoot); } catch (XmlPullParserException e) { InflateException ex = new InflateException(e.getMessage()); ex.initCause(e); throw ex; } catch (IOException e) { InflateException ex = new InflateException(parser.getPositionDescription() + ": " + e.getMessage()); ex.initCause(e); throw ex; } finally { parser.close(); } } // // Transition loading // private Transition createTransitionFromXml(XmlPullParser parser, AttributeSet attrs, TransitionSet transitionSet) throws XmlPullParserException, IOException { Transition transition = null; // Make sure we are on a start tag. int type; int depth = parser.getDepth(); while (((type = parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) { boolean newTransition = false; if (type != XmlPullParser.START_TAG) { continue; } String name = parser.getName(); if ("fade".equals(name)) { TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.Fade); int fadingMode = a.getInt(R.styleable.Fade_fadingMode, Fade.IN | Fade.OUT); transition = new Fade(fadingMode); newTransition = true; } else if ("changeBounds".equals(name)) { transition = new ChangeBounds(); newTransition = true; } else if ("slide".equals(name)) { transition = new Slide(); newTransition = true; } else if ("autoTransition".equals(name)) { transition = new AutoTransition(); newTransition = true; } else if ("recolor".equals(name)) { transition = new Recolor(); newTransition = true; } else if ("transitionSet".equals(name)) { transition = new TransitionSet(); TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.TransitionSet); int ordering = a.getInt(R.styleable.TransitionSet_transitionOrdering, TransitionSet.ORDERING_TOGETHER); ((TransitionSet) transition).setOrdering(ordering); createTransitionFromXml(parser, attrs, ((TransitionSet) transition)); a.recycle(); newTransition = true; } else if ("targets".equals(name)) { if (parser.getDepth() - 1 > depth && transition != null) { // We're inside the child tag - add targets to the child getTargetIds(parser, attrs, transition); } else if (parser.getDepth() - 1 == depth && transitionSet != null) { // add targets to the set getTargetIds(parser, attrs, transitionSet); } } if (transition != null || "targets".equals(name)) { if (newTransition) { loadTransition(transition, attrs); if (transitionSet != null) { transitionSet.addTransition(transition); } } } else { throw new RuntimeException("Unknown scene name: " + parser.getName()); } } return transition; } private void getTargetIds(XmlPullParser parser, AttributeSet attrs, Transition transition) throws XmlPullParserException, IOException { // Make sure we are on a start tag. int type; int depth = parser.getDepth(); ArrayList<Integer> targetIds = new ArrayList<Integer>(); while (((type = parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) { if (type != XmlPullParser.START_TAG) { continue; } String name = parser.getName(); if (name.equals("target")) { TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.TransitionTarget); int id = a.getResourceId(R.styleable.TransitionTarget_targetId, -1); if (id >= 0) { targetIds.add(id); } } else { throw new RuntimeException("Unknown scene name: " + parser.getName()); } } int numTargets = targetIds.size(); if (numTargets > 0) { for (int i = 0; i < numTargets; ++i) { transition.addTarget(targetIds.get(i)); } } } private Transition loadTransition(Transition transition, AttributeSet attrs) throws Resources.NotFoundException { TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.Transition); long duration = a.getInt(R.styleable.Transition_duration, -1); if (duration >= 0) { transition.setDuration(duration); } long startDelay = a.getInt(R.styleable.Transition_startDelay, -1); if (startDelay > 0) { transition.setStartDelay(startDelay); } final int resID = a.getResourceId(R.styleable.Transition_interpolator, 0); if (resID > 0) { transition.setInterpolator(AnimationUtils.loadInterpolator(mContext, resID)); } a.recycle(); return transition; } // // TransitionManager loading // private TransitionManager createTransitionManagerFromXml(XmlPullParser parser, AttributeSet attrs, ViewGroup sceneRoot) throws XmlPullParserException, IOException { // Make sure we are on a start tag. int type; int depth = parser.getDepth(); TransitionManager transitionManager = null; while (((type = parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) { if (type != XmlPullParser.START_TAG) { continue; } String name = parser.getName(); if (name.equals("transitionManager")) { transitionManager = new TransitionManager(); } else if (name.equals("transition") && (transitionManager != null)) { loadTransition(attrs, sceneRoot, transitionManager); } else { throw new RuntimeException("Unknown scene name: " + parser.getName()); } } return transitionManager; } private void loadTransition(AttributeSet attrs, ViewGroup sceneRoot, TransitionManager transitionManager) throws Resources.NotFoundException { TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.TransitionManager); int transitionId = a.getResourceId(R.styleable.TransitionManager_transition, -1); Scene fromScene = null, toScene = null; int fromId = a.getResourceId(R.styleable.TransitionManager_fromScene, -1); if (fromId >= 0) fromScene = Scene.getSceneForLayout(sceneRoot, fromId, mContext); int toId = a.getResourceId(R.styleable.TransitionManager_toScene, -1); if (toId >= 0) toScene = Scene.getSceneForLayout(sceneRoot, toId, mContext); if (transitionId >= 0) { Transition transition = inflateTransition(transitionId); if (transition != null) { if (fromScene != null) { if (toScene == null) { throw new RuntimeException( "No matching toScene for given fromScene " + "for transition ID " + transitionId); } else { transitionManager.setTransition(fromScene, toScene, transition); } } else if (toId >= 0) { transitionManager.setTransition(toScene, transition); } } } a.recycle(); } }