| /* |
| * Copyright (C) 2017 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.support.transition; |
| |
| import android.content.Context; |
| import android.content.res.Resources; |
| import android.content.res.TypedArray; |
| import android.content.res.XmlResourceParser; |
| import android.support.annotation.NonNull; |
| import android.support.v4.content.res.TypedArrayUtils; |
| import android.support.v4.util.ArrayMap; |
| import android.util.AttributeSet; |
| import android.util.Xml; |
| import android.view.InflateException; |
| import android.view.ViewGroup; |
| |
| import org.xmlpull.v1.XmlPullParser; |
| import org.xmlpull.v1.XmlPullParserException; |
| |
| import java.io.IOException; |
| import java.lang.reflect.Constructor; |
| |
| /** |
| * This class inflates scenes and transitions from resource files. |
| */ |
| public class TransitionInflater { |
| |
| private static final Class<?>[] CONSTRUCTOR_SIGNATURE = |
| new Class[]{Context.class, AttributeSet.class}; |
| private static final ArrayMap<String, Constructor> CONSTRUCTORS = new ArrayMap<>(); |
| |
| private final Context mContext; |
| |
| private TransitionInflater(@NonNull Context context) { |
| mContext = context; |
| } |
| |
| /** |
| * Obtains the TransitionInflater from the given context. |
| */ |
| public static TransitionInflater from(Context context) { |
| return new TransitionInflater(context); |
| } |
| |
| /** |
| * 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) { |
| throw new InflateException(e.getMessage(), e); |
| } catch (IOException e) { |
| throw new InflateException( |
| parser.getPositionDescription() + ": " + e.getMessage(), e); |
| } 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, Transition parent) |
| throws XmlPullParserException, IOException { |
| |
| Transition transition = null; |
| |
| // Make sure we are on a start tag. |
| int type; |
| int depth = parser.getDepth(); |
| |
| TransitionSet transitionSet = (parent instanceof TransitionSet) |
| ? (TransitionSet) parent : null; |
| |
| while (((type = parser.next()) != XmlPullParser.END_TAG || parser.getDepth() > depth) |
| && type != XmlPullParser.END_DOCUMENT) { |
| |
| if (type != XmlPullParser.START_TAG) { |
| continue; |
| } |
| |
| // TODO: Add more Transition types |
| String name = parser.getName(); |
| if ("fade".equals(name)) { |
| transition = new Fade(mContext, attrs); |
| } else if ("changeBounds".equals(name)) { |
| transition = new ChangeBounds(mContext, attrs); |
| } else if ("explode".equals(name)) { |
| transition = new Explode(mContext, attrs); |
| } else if ("changeTransform".equals(name)) { |
| transition = new ChangeTransform(mContext, attrs); |
| } else if ("changeClipBounds".equals(name)) { |
| transition = new ChangeClipBounds(mContext, attrs); |
| } else if ("autoTransition".equals(name)) { |
| transition = new AutoTransition(mContext, attrs); |
| } else if ("transitionSet".equals(name)) { |
| transition = new TransitionSet(mContext, attrs); |
| } else if ("transition".equals(name)) { |
| transition = (Transition) createCustom(attrs, Transition.class, "transition"); |
| } else if ("targets".equals(name)) { |
| getTargetIds(parser, attrs, parent); |
| } else { |
| throw new RuntimeException("Unknown scene name: " + parser.getName()); |
| } |
| if (transition != null) { |
| if (!parser.isEmptyElementTag()) { |
| createTransitionFromXml(parser, attrs, transition); |
| } |
| if (transitionSet != null) { |
| transitionSet.addTransition(transition); |
| transition = null; |
| } else if (parent != null) { |
| throw new InflateException("Could not add transition to another transition."); |
| } |
| } |
| } |
| |
| return transition; |
| } |
| |
| private Object createCustom(AttributeSet attrs, Class expectedType, String tag) { |
| String className = attrs.getAttributeValue(null, "class"); |
| |
| if (className == null) { |
| throw new InflateException(tag + " tag must have a 'class' attribute"); |
| } |
| |
| try { |
| synchronized (CONSTRUCTORS) { |
| Constructor constructor = CONSTRUCTORS.get(className); |
| if (constructor == null) { |
| Class<?> c = mContext.getClassLoader().loadClass(className) |
| .asSubclass(expectedType); |
| if (c != null) { |
| constructor = c.getConstructor(CONSTRUCTOR_SIGNATURE); |
| constructor.setAccessible(true); |
| CONSTRUCTORS.put(className, constructor); |
| } |
| } |
| //noinspection ConstantConditions |
| return constructor.newInstance(mContext, attrs); |
| } |
| } catch (Exception e) { |
| throw new InflateException("Could not instantiate " + expectedType + " class " |
| + className, e); |
| } |
| } |
| |
| 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(); |
| |
| 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, Styleable.TRANSITION_TARGET); |
| int id = TypedArrayUtils.getNamedResourceId(a, parser, "targetId", |
| Styleable.TransitionTarget.TARGET_ID, 0); |
| String transitionName; |
| if (id != 0) { |
| transition.addTarget(id); |
| } else if ((id = TypedArrayUtils.getNamedResourceId(a, parser, "excludeId", |
| Styleable.TransitionTarget.EXCLUDE_ID, 0)) != 0) { |
| transition.excludeTarget(id, true); |
| } else if ((transitionName = TypedArrayUtils.getNamedString(a, parser, "targetName", |
| Styleable.TransitionTarget.TARGET_NAME)) != null) { |
| transition.addTarget(transitionName); |
| } else if ((transitionName = TypedArrayUtils.getNamedString(a, parser, |
| "excludeName", Styleable.TransitionTarget.EXCLUDE_NAME)) != null) { |
| transition.excludeTarget(transitionName, true); |
| } else { |
| String className = TypedArrayUtils.getNamedString(a, parser, |
| "excludeClass", Styleable.TransitionTarget.EXCLUDE_CLASS); |
| try { |
| if (className != null) { |
| Class clazz = Class.forName(className); |
| transition.excludeTarget(clazz, true); |
| } else if ((className = TypedArrayUtils.getNamedString(a, parser, |
| "targetClass", Styleable.TransitionTarget.TARGET_CLASS)) != null) { |
| Class clazz = Class.forName(className); |
| transition.addTarget(clazz); |
| } |
| } catch (ClassNotFoundException e) { |
| a.recycle(); |
| throw new RuntimeException("Could not create " + className, e); |
| } |
| } |
| a.recycle(); |
| } else { |
| throw new RuntimeException("Unknown scene name: " + parser.getName()); |
| } |
| } |
| } |
| |
| // |
| // 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, parser, sceneRoot, transitionManager); |
| } else { |
| throw new RuntimeException("Unknown scene name: " + parser.getName()); |
| } |
| } |
| return transitionManager; |
| } |
| |
| private void loadTransition(AttributeSet attrs, XmlPullParser parser, ViewGroup sceneRoot, |
| TransitionManager transitionManager) throws Resources.NotFoundException { |
| |
| TypedArray a = mContext.obtainStyledAttributes(attrs, Styleable.TRANSITION_MANAGER); |
| int transitionId = TypedArrayUtils.getNamedResourceId(a, parser, "transition", |
| Styleable.TransitionManager.TRANSITION, -1); |
| int fromId = TypedArrayUtils.getNamedResourceId(a, parser, "fromScene", |
| Styleable.TransitionManager.FROM_SCENE, -1); |
| Scene fromScene = (fromId < 0) ? null : Scene.getSceneForLayout(sceneRoot, fromId, |
| mContext); |
| int toId = TypedArrayUtils.getNamedResourceId(a, parser, "toScene", |
| Styleable.TransitionManager.TO_SCENE, -1); |
| Scene toScene = (toId < 0) ? null : Scene.getSceneForLayout(sceneRoot, toId, mContext); |
| |
| if (transitionId >= 0) { |
| Transition transition = inflateTransition(transitionId); |
| if (transition != null) { |
| if (toScene == null) { |
| throw new RuntimeException("No toScene for transition ID " + transitionId); |
| } |
| if (fromScene == null) { |
| transitionManager.setTransition(toScene, transition); |
| } else { |
| transitionManager.setTransition(fromScene, toScene, transition); |
| } |
| } |
| } |
| a.recycle(); |
| } |
| |
| } |