Java tutorial
/* * 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.support.v17.leanback.widget; import android.os.Handler; import android.support.v4.app.ActivityCompat; import android.support.v4.app.SharedElementCallback; import android.support.v4.view.ViewCompat; import android.support.v17.leanback.R; import android.support.v17.leanback.transition.TransitionListener; import android.support.v17.leanback.transition.TransitionHelper; import android.support.v17.leanback.widget.FullWidthDetailsOverviewRowPresenter.ViewHolder; import android.app.Activity; import android.content.Intent; import android.graphics.Matrix; import android.text.TextUtils; import android.util.Log; import android.view.View; import android.view.ViewGroup; import android.view.View.MeasureSpec; import android.widget.ImageView; import android.widget.ImageView.ScaleType; import java.util.List; /** * Helper class to assist delayed shared element activity transition for view created by * {@link FullWidthDetailsOverviewRowPresenter}. User must call * {@link #setSharedElementEnterTransition(Activity, String, long)} during activity onCreate() and * call {@link FullWidthDetailsOverviewRowPresenter#setListener(FullWidthDetailsOverviewRowPresenter.Listener)}. * The helper implements {@link FullWidthDetailsOverviewRowPresenter.Listener} and starts delayed * activity transition once {@link FullWidthDetailsOverviewRowPresenter.Listener#onBindLogo(ViewHolder)} * is called. */ public class FullWidthDetailsOverviewSharedElementHelper extends FullWidthDetailsOverviewRowPresenter.Listener { private static final String TAG = "FullWidthDetailsOverviewSharedElementHelper"; private static final boolean DEBUG = false; private static final long DEFAULT_TIMEOUT = 5000; private ViewHolder mViewHolder; private Activity mActivityToRunTransition; private boolean mStartedPostpone; private String mSharedElementName; private boolean mAutoStartSharedElementTransition = true; public void setSharedElementEnterTransition(Activity activity, String sharedElementName) { setSharedElementEnterTransition(activity, sharedElementName, DEFAULT_TIMEOUT); } public void setSharedElementEnterTransition(Activity activity, String sharedElementName, long timeoutMs) { if (activity == null && !TextUtils.isEmpty(sharedElementName) || activity != null && TextUtils.isEmpty(sharedElementName)) { throw new IllegalArgumentException(); } if (activity == mActivityToRunTransition && TextUtils.equals(sharedElementName, mSharedElementName)) { return; } mActivityToRunTransition = activity; mSharedElementName = sharedElementName; if (DEBUG) { Log.d(TAG, "postponeEnterTransition " + mActivityToRunTransition); } Object transition = TransitionHelper.getSharedElementEnterTransition(activity.getWindow()); setAutoStartSharedElementTransition(transition != null); ActivityCompat.postponeEnterTransition(mActivityToRunTransition); if (timeoutMs > 0) { new Handler().postDelayed(new Runnable() { @Override public void run() { if (DEBUG) { Log.d(TAG, "timeout " + mActivityToRunTransition); } startPostponedEnterTransitionInternal(); } }, timeoutMs); } } /** * Enable or disable auto startPostponedEnterTransition() when bound to logo. When it's * disabled, app must call {@link #startPostponedEnterTransition()} to kick off * windowEnterTransition. By default, it is disabled when there is no * windowEnterSharedElementTransition set on the activity. */ public void setAutoStartSharedElementTransition(boolean enabled) { mAutoStartSharedElementTransition = enabled; } /** * Returns true if auto startPostponedEnterTransition() when bound to logo. When it's * disabled, app must call {@link #startPostponedEnterTransition()} to kick off * windowEnterTransition. By default, it is disabled when there is no * windowEnterSharedElementTransition set on the activity. */ public boolean getAutoStartSharedElementTransition() { return mAutoStartSharedElementTransition; } @Override public void onBindLogo(ViewHolder vh) { if (DEBUG) { Log.d(TAG, "onBindLogo, could start transition of " + mActivityToRunTransition); } mViewHolder = vh; if (!mAutoStartSharedElementTransition) { return; } if (mViewHolder != null) { if (DEBUG) { Log.d(TAG, "rebind? clear transitionName on current viewHolder " + mViewHolder.getOverviewView()); } ViewCompat.setTransitionName(mViewHolder.getLogoViewHolder().view, null); } // After we got a image drawable, we can determine size of right panel. // We want right panel to have fixed size so that the right panel don't change size // when the overview is layout as a small bounds in transition. mViewHolder.getDetailsDescriptionFrame().postOnAnimation(new Runnable() { @Override public void run() { if (DEBUG) { Log.d(TAG, "setTransitionName " + mViewHolder.getOverviewView()); } ViewCompat.setTransitionName(mViewHolder.getLogoViewHolder().view, mSharedElementName); Object transition = TransitionHelper .getSharedElementEnterTransition(mActivityToRunTransition.getWindow()); if (transition != null) { TransitionHelper.addTransitionListener(transition, new TransitionListener() { @Override public void onTransitionEnd(Object transition) { if (DEBUG) { Log.d(TAG, "onTransitionEnd " + mActivityToRunTransition); } // after transition if the action row still focused, transfer // focus to its children if (mViewHolder.getActionsRow().isFocused()) { mViewHolder.getActionsRow().requestFocus(); } TransitionHelper.removeTransitionListener(transition, this); } }); } startPostponedEnterTransitionInternal(); } }); } /** * Manually start postponed enter transition. */ public void startPostponedEnterTransition() { new Handler().post(new Runnable() { @Override public void run() { startPostponedEnterTransitionInternal(); } }); } private void startPostponedEnterTransitionInternal() { if (!mStartedPostpone && mViewHolder != null) { if (DEBUG) { Log.d(TAG, "startPostponedEnterTransition " + mActivityToRunTransition); } ActivityCompat.startPostponedEnterTransition(mActivityToRunTransition); mStartedPostpone = true; } } }