// Copyright 2019 Google Inc. All Rights Reserved.
//
// 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.google.androidbrowserhelper.trusted;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.util.Log;
import androidx.annotation.Nullable;
import androidx.browser.customtabs.CustomTabsClient;
import androidx.browser.customtabs.CustomTabsIntent;
import androidx.browser.customtabs.CustomTabsService;
import androidx.browser.customtabs.CustomTabsServiceConnection;
import androidx.browser.customtabs.CustomTabsSession;
import androidx.browser.customtabs.TrustedWebUtils;
import androidx.browser.trusted.Token;
import androidx.browser.trusted.TokenStore;
import androidx.browser.trusted.TrustedWebActivityIntentBuilder;
import androidx.core.content.ContextCompat;
import com.google.androidbrowserhelper.trusted.splashscreens.SplashScreenStrategy;
/**
* Encapsulates the steps necessary to launch a Trusted Web Activity, such as establishing a
* connection with {@link CustomTabsService}.
*/
public class TwaLauncher {
private static final String TAG = "TwaLauncher";
private static final int DEFAULT_SESSION_ID = 96375;
private static final String ARC_FEATURE = "org.chromium.arc";
public static final FallbackStrategy CCT_FALLBACK_STRATEGY =
(context, twaBuilder, providerPackage, completionCallback) -> {
// CustomTabsIntent will fall back to launching the Browser if there are no Custom Tabs
// providers installed.
CustomTabsIntent intent = twaBuilder.buildCustomTabsIntent();
if (providerPackage != null) {
intent.intent.setPackage(providerPackage);
}
// Add the TWA flag to the intent if the app is running on ARC++ on Chrome OS.
if (context.getPackageManager().hasSystemFeature(ARC_FEATURE)) {
intent.intent.putExtra(TrustedWebUtils.EXTRA_LAUNCH_AS_TRUSTED_WEB_ACTIVITY, true);
}
intent.launchUrl(context, twaBuilder.getUri());
if (completionCallback != null) {
completionCallback.run();
}
};
public static final FallbackStrategy WEBVIEW_FALLBACK_STRATEGY =
(context, twaBuilder, providerPackage, completionCallback) -> {
Intent intent = WebViewFallbackActivity.createLaunchIntent(context,
twaBuilder.getUri(), LauncherActivityMetadata.parse(context));
context.startActivity(intent);
if (completionCallback != null) {
completionCallback.run();
}
};
private final Context mContext;
@Nullable
private final String mProviderPackage;
@TwaProviderPicker.LaunchMode
private final int mLaunchMode;
private final int mSessionId;
@Nullable
private TwaCustomTabsServiceConnection mServiceConnection;
@Nullable
private CustomTabsSession mSession;
private TokenStore mTokenStore;
private boolean mDestroyed;
public interface FallbackStrategy {
void launch(Context context,
TrustedWebActivityIntentBuilder twaBuilder,
@Nullable String providerPackage,
@Nullable Runnable completionCallback);
}
/**
* Creates an instance that will automatically choose the browser to launch a TWA in.
* If no browser supports TWA, will launch a usual Custom Tab (see {@link TwaProviderPicker}.
*/
public TwaLauncher(Context context) {
this(context, null);
}
/**
* Same as above, but also allows to specify a browser to launch. If specified, it is assumed to
* support TWAs.
*/
public TwaLauncher(Context context, @Nullable String providerPackage) {
this(context, providerPackage, DEFAULT_SESSION_ID,
new SharedPreferencesTokenStore(context));
}
/**
* Same as above, but also accepts a session id. This allows to launch multiple TWAs in the same
* task.
*/
public TwaLauncher(Context context, @Nullable String providerPackage, int sessionId,
TokenStore tokenStore) {
mContext = context;
mSessionId = sessionId;
mTokenStore = tokenStore;
if (providerPackage == null) {
TwaProviderPicker.Action action =
TwaProviderPicker.pickProvider(context.getPackageManager());
mProviderPackage = action.provider;
mLaunchMode = action.launchMode;
} else {
mProviderPackage = providerPackage;
mLaunchMode = TwaProviderPicker.LaunchMode.TRUSTED_WEB_ACTIVITY;
}
}
/**
* Opens the specified url in a TWA.
* When TWA is already running in the current task, the url will be opened in existing TWA,
* if the same instance TwaLauncher is used. If another instance of TwaLauncher is used,
* the TWA will be reused only if the session ids match (see constructors).
*
* @param url Url to open.
*/
public void launch(Uri url) {
launch(new TrustedWebActivityIntentBuilder(url), null, null);
}
/**
* Similar to {@link #launch(Uri)}, but allows more customization.
*
* @param twaBuilder {@link TrustedWebActivityIntentBuilder} containing the url to open, along with
* optional parameters: status bar color, additional trusted origins, etc.
* @param splashScreenStrategy {@link SplashScreenStrategy} to use for showing splash screens,
* null if splash screen not needed.
* @param completionCallback Callback triggered when the url has been opened.
* @param fallbackStrategy Called when there is no TWA provider available or when launching
* the Trusted Web Activity fails.
*/
public void launch(TrustedWebActivityIntentBuilder twaBuilder,
@Nullable SplashScreenStrategy splashScreenStrategy,
@Nullable Runnable completionCallback,
FallbackStrategy fallbackStrategy) {
if (mDestroyed) {
throw new IllegalStateException("TwaLauncher already destroyed");
}
if (mLaunchMode == TwaProviderPicker.LaunchMode.TRUSTED_WEB_ACTIVITY) {
launchTwa(twaBuilder, splashScreenStrategy, completionCallback, fallbackStrategy);
} else {
fallbackStrategy.launch(mContext, twaBuilder, mProviderPackage, completionCallback);
}
}
/**
* Similar to {@link #launch(Uri)}, but allows more customization. Uses a Custom Tabs fallback
* when a TWA provider is not available or when launching a TWA fails.
*
* @param twaBuilder {@link TrustedWebActivityIntentBuilder} containing the url to open, along with
* optional parameters: status bar color, additional trusted origins, etc.
* @param splashScreenStrategy {@link SplashScreenStrategy} to use for showing splash screens,
* null if splash screen not needed.
* @param completionCallback Callback triggered when the url has been opened.
*/
public void launch(TrustedWebActivityIntentBuilder twaBuilder,
@Nullable SplashScreenStrategy splashScreenStrategy,
@Nullable Runnable completionCallback) {
launch(twaBuilder, splashScreenStrategy, completionCallback, CCT_FALLBACK_STRATEGY);
}
private void launchTwa(TrustedWebActivityIntentBuilder twaBuilder,
@Nullable SplashScreenStrategy splashScreenStrategy,
@Nullable Runnable completionCallback,
FallbackStrategy fallbackStrategy) {
if (splashScreenStrategy != null) {
splashScreenStrategy.onTwaLaunchInitiated(mProviderPackage, twaBuilder);
}
Runnable onSessionCreatedRunnable = () ->
launchWhenSessionEstablished(twaBuilder, splashScreenStrategy, completionCallback);
if (mSession != null) {
onSessionCreatedRunnable.run();
return;
}
Runnable onSessionCreationFailedRunnable = () -> {
// The provider has been unable to create a session for us, we can't launch a
// Trusted Web Activity. We launch a fallback specially designed to provide the
// best user experience.
fallbackStrategy.launch(mContext, twaBuilder, mProviderPackage, completionCallback);
};
if (mServiceConnection == null) {
mServiceConnection = new TwaCustomTabsServiceConnection();
}
mServiceConnection.setSessionCreationRunnables(
onSessionCreatedRunnable, onSessionCreationFailedRunnable);
CustomTabsClient.bindCustomTabsService(mContext, mProviderPackage, mServiceConnection);
}
private void launchWhenSessionEstablished(TrustedWebActivityIntentBuilder twaBuilder,
@Nullable SplashScreenStrategy splashScreenStrategy,
@Nullable Runnable completionCallback) {
if (mSession == null) {
throw new IllegalStateException("mSession is null in launchWhenSessionEstablished");
}
if (splashScreenStrategy != null) {
splashScreenStrategy.configureTwaBuilder(twaBuilder, mSession,
() -> launchWhenSplashScreenReady(twaBuilder, completionCallback));
} else {
launchWhenSplashScreenReady(twaBuilder, completionCallback);
}
}
private void launchWhenSplashScreenReady(TrustedWebActivityIntentBuilder builder,
@Nullable Runnable completionCallback) {
if (mDestroyed || mSession == null) {
return; // Service was disconnected and / or TwaLauncher was destroyed while preparing
// the splash screen (e.g. user closed the app). See https://crbug.com/1052367
// for further details.
}
Log.d(TAG, "Launching Trusted Web Activity.");
Intent intent = builder.build(mSession).getIntent();
FocusActivity.addToIntent(intent, mContext);
ContextCompat.startActivity(mContext, intent, null);
// Remember who we connect to as the package that is allowed to delegate notifications
// to us.
mTokenStore.store(Token.create(mProviderPackage, mContext.getPackageManager()));
if (completionCallback != null) {
completionCallback.run();
}
}
/**
* Performs clean-up.
*/
public void destroy() {
if (mDestroyed) {
return;
}
if (mServiceConnection != null) {
mContext.unbindService(mServiceConnection);
}
mDestroyed = true;
}
/**
* Returns package name of the browser this TwaLauncher is launching.
*/
@Nullable
public String getProviderPackage() {
return mProviderPackage;
}
private class TwaCustomTabsServiceConnection extends CustomTabsServiceConnection {
private Runnable mOnSessionCreatedRunnable;
private Runnable mOnSessionCreationFailedRunnable;
private void setSessionCreationRunnables(@Nullable Runnable onSuccess,
@Nullable Runnable onFailure) {
mOnSessionCreatedRunnable = onSuccess;
mOnSessionCreationFailedRunnable = onFailure;
}
@Override
public void onCustomTabsServiceConnected(ComponentName componentName,
CustomTabsClient client) {
if (!ChromeLegacyUtils
.supportsLaunchWithoutWarmup(mContext.getPackageManager(), mProviderPackage)) {
client.warmup(0);
}
mSession = client.newSession(null, mSessionId);
if (mSession != null && mOnSessionCreatedRunnable != null) {
mOnSessionCreatedRunnable.run();
} else if (mSession == null && mOnSessionCreationFailedRunnable != null) {
mOnSessionCreationFailedRunnable.run();
}
mOnSessionCreatedRunnable = null;
mOnSessionCreationFailedRunnable = null;
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
mSession = null;
}
}
}
