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 com.android.launcher4.compat; import android.content.Context; import android.content.SharedPreferences; import android.text.TextUtils; import android.util.Log; import com.android.launcher4.LauncherAppState; import org.json.JSONException; import org.json.JSONObject; import org.json.JSONStringer; import org.json.JSONTokener; import java.util.ArrayList; import java.util.HashSet; public class PackageInstallerCompatV16 extends PackageInstallerCompat { private static final String TAG = "PackageInstallerCompatV16"; private static final boolean DEBUG = false; private static final String KEY_PROGRESS = "progress"; private static final String KEY_STATE = "state"; private static final String PREFS = "com.android.launcher4.compat.PackageInstallerCompatV16.queue"; protected final SharedPreferences mPrefs; boolean mUseQueue; boolean mFinishedBind; boolean mReplayPending; PackageInstallerCompatV16(Context context) { mPrefs = context.getSharedPreferences(PREFS, Context.MODE_PRIVATE); } @Override public void onPause() { mUseQueue = true; if (DEBUG) Log.d(TAG, "updates paused"); } @Override public void onResume() { mUseQueue = false; if (mFinishedBind) { replayUpdates(); } } @Override public void onFinishBind() { mFinishedBind = true; if (!mUseQueue) { replayUpdates(); } } @Override public void onStop() { } private void replayUpdates() { if (DEBUG) Log.d(TAG, "updates resumed"); LauncherAppState app = LauncherAppState.getInstanceNoCreate(); if (app == null) { mReplayPending = true; // try again later if (DEBUG) Log.d(TAG, "app is null, delaying send"); return; } mReplayPending = false; ArrayList<PackageInstallInfo> updates = new ArrayList<PackageInstallInfo>(); for (String packageName : mPrefs.getAll().keySet()) { final String json = mPrefs.getString(packageName, null); if (!TextUtils.isEmpty(json)) { updates.add(infoFromJson(packageName, json)); } } if (!updates.isEmpty()) { sendUpdate(app, updates); } } /** * This should be called by the implementations to register a package update. */ @Override public synchronized void recordPackageUpdate(String packageName, int state, int progress) { SharedPreferences.Editor editor = mPrefs.edit(); PackageInstallInfo installInfo = new PackageInstallInfo(packageName); installInfo.progress = progress; installInfo.state = state; if (state == STATUS_INSTALLED) { // no longer necessary to track this package editor.remove(packageName); if (DEBUG) Log.d(TAG, "no longer tracking " + packageName); } else { editor.putString(packageName, infoToJson(installInfo)); if (DEBUG) Log.d(TAG, "saved state: " + infoToJson(installInfo) + " for package: " + packageName); } editor.commit(); if (!mUseQueue) { if (mReplayPending) { replayUpdates(); } else if (state != STATUS_INSTALLED) { LauncherAppState app = LauncherAppState.getInstanceNoCreate(); ArrayList<PackageInstallInfo> update = new ArrayList<PackageInstallInfo>(); update.add(installInfo); sendUpdate(app, update); } } } private void sendUpdate(LauncherAppState app, ArrayList<PackageInstallInfo> updates) { if (app == null) { mReplayPending = true; // try again later if (DEBUG) Log.d(TAG, "app is null, delaying send"); } else { app.setPackageState(updates); } } private static PackageInstallInfo infoFromJson(String packageName, String json) { PackageInstallInfo info = new PackageInstallInfo(packageName); try { JSONObject object = (JSONObject) new JSONTokener(json).nextValue(); info.state = object.getInt(KEY_STATE); info.progress = object.getInt(KEY_PROGRESS); } catch (JSONException e) { Log.e(TAG, "failed to deserialize app state update", e); } return info; } private static String infoToJson(PackageInstallInfo info) { String value = null; try { JSONStringer json = new JSONStringer().object().key(KEY_STATE).value(info.state).key(KEY_PROGRESS) .value(info.progress).endObject(); value = json.toString(); } catch (JSONException e) { Log.e(TAG, "failed to serialize app state update", e); } return value; } @Override public HashSet<String> updateAndGetActiveSessionCache() { return new HashSet<String>(); } }