Java tutorial
/* * Copyright (C) 2010 Google Inc. * * 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.googlecode.android_scripting.interpreter.html; import android.app.Activity; import android.content.res.Resources; import android.graphics.Bitmap; import android.graphics.drawable.BitmapDrawable; import android.net.Uri; import android.view.ContextMenu; import android.view.ContextMenu.ContextMenuInfo; import android.view.Menu; import android.view.View; import android.view.Window; import android.webkit.JsPromptResult; import android.webkit.JsResult; import android.webkit.WebChromeClient; import android.webkit.WebView; import android.webkit.WebViewClient; import com.googlecode.android_scripting.FileUtils; import com.googlecode.android_scripting.Log; import com.googlecode.android_scripting.SingleThreadExecutor; import com.googlecode.android_scripting.event.Event; import com.googlecode.android_scripting.facade.EventFacade; import com.googlecode.android_scripting.facade.ui.UiFacade; import com.googlecode.android_scripting.future.FutureActivityTask; import com.googlecode.android_scripting.interpreter.InterpreterConstants; import com.googlecode.android_scripting.jsonrpc.JsonBuilder; import com.googlecode.android_scripting.jsonrpc.JsonRpcResult; import com.googlecode.android_scripting.jsonrpc.RpcReceiver; import com.googlecode.android_scripting.jsonrpc.RpcReceiverManager; import com.googlecode.android_scripting.rpc.MethodDescriptor; import com.googlecode.android_scripting.rpc.RpcError; import java.io.File; import java.io.IOException; import java.util.HashMap; import java.util.HashSet; import java.util.Map; import java.util.Set; import java.util.concurrent.ExecutorService; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; /** * @author Alexey Reznichenko (alexey.reznichenko@gmail.com) */ public class HtmlActivityTask extends FutureActivityTask<Void> { private static final String HTTP = "http"; private static final String ANDROID_PROTOTYPE_JS = "Android.prototype.%1$s = function(var_args) { " + "return this._call(\"%1$s\", Array.prototype.slice.call(arguments)); };"; private static final String PREFIX = "file://"; private static final String BASE_URL = PREFIX + InterpreterConstants.SCRIPTS_ROOT; private final RpcReceiverManager mReceiverManager; private final String mJsonSource; private final String mAndroidJsSource; private final String mAPIWrapperSource; private final String mUrl; private final JavaScriptWrapper mWrapper; private final HtmlEventObserver mObserver; private final UiFacade mUiFacade; private ChromeClient mChromeClient; private WebView mView; private MyWebViewClient mWebViewClient; private static HtmlActivityTask reference; private boolean mDestroyManager; public HtmlActivityTask(RpcReceiverManager manager, String androidJsSource, String jsonSource, String url, boolean destroyManager) { reference = this; mReceiverManager = manager; mJsonSource = jsonSource; mAndroidJsSource = androidJsSource; mAPIWrapperSource = generateAPIWrapper(); mWrapper = new JavaScriptWrapper(); mObserver = new HtmlEventObserver(); mReceiverManager.getReceiver(EventFacade.class).addGlobalEventObserver(mObserver); mUiFacade = mReceiverManager.getReceiver(UiFacade.class); mUrl = url; mDestroyManager = destroyManager; } public RpcReceiverManager getRpcReceiverManager() { return mReceiverManager; } /* * New WebviewClient */ private class MyWebViewClient extends WebViewClient { @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { /* * if (Uri.parse(url).getHost().equals("www.example.com")) { // This is my web site, so do not * override; let my WebView load the page return false; } // Otherwise, the link is not for a * page on my site, so launch another Activity that handles URLs Intent intent = new * Intent(Intent.ACTION_VIEW, Uri.parse(url)); startActivity(intent); */ if (!HTTP.equals(Uri.parse(url).getScheme())) { String source = null; try { source = FileUtils.readToString(new File(Uri.parse(url).getPath())); } catch (IOException e) { throw new RuntimeException(e); } source = "<script>" + mJsonSource + "</script>" + "<script>" + mAndroidJsSource + "</script>" + "<script>" + mAPIWrapperSource + "</script>" + source; mView.loadDataWithBaseURL(BASE_URL, source, "text/html", "utf-8", null); } else { mView.loadUrl(url); } return true; } } @Override public void onCreate() { mView = new WebView(getActivity()); mView.setId(1); mView.getSettings().setJavaScriptEnabled(true); mView.addJavascriptInterface(mWrapper, "_rpc_wrapper"); mView.addJavascriptInterface(new Object() { @SuppressWarnings("unused") public void register(String event, int id) { mObserver.register(event, id); } }, "_callback_wrapper"); getActivity().setContentView(mView); mView.setOnCreateContextMenuListener(getActivity()); mChromeClient = new ChromeClient(getActivity()); mWebViewClient = new MyWebViewClient(); mView.setWebChromeClient(mChromeClient); mView.setWebViewClient(mWebViewClient); mView.loadUrl("javascript:" + mJsonSource); mView.loadUrl("javascript:" + mAndroidJsSource); mView.loadUrl("javascript:" + mAPIWrapperSource); load(); } private void load() { if (!HTTP.equals(Uri.parse(mUrl).getScheme())) { String source = null; try { source = FileUtils.readToString(new File(Uri.parse(mUrl).getPath())); } catch (IOException e) { throw new RuntimeException(e); } mView.loadDataWithBaseURL(BASE_URL, source, "text/html", "utf-8", null); } else { mView.loadUrl(mUrl); } } @Override public void onDestroy() { mReceiverManager.getReceiver(EventFacade.class).removeEventObserver(mObserver); if (mDestroyManager) { mReceiverManager.shutdown(); } mView.destroy(); mView = null; reference = null; setResult(null); } public static void shutdown() { if (HtmlActivityTask.reference != null) { HtmlActivityTask.reference.finish(); } } @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { mUiFacade.onCreateContextMenu(menu, v, menuInfo); } @Override public boolean onPrepareOptionsMenu(Menu menu) { return mUiFacade.onPrepareOptionsMenu(menu); } private String generateAPIWrapper() { StringBuilder wrapper = new StringBuilder(); for (Class<? extends RpcReceiver> clazz : mReceiverManager.getRpcReceiverClasses()) { for (MethodDescriptor rpc : MethodDescriptor.collectFrom(clazz)) { wrapper.append(String.format(ANDROID_PROTOTYPE_JS, rpc.getName())); } } return wrapper.toString(); } private class JavaScriptWrapper { @SuppressWarnings("unused") public String call(String data) throws JSONException { Log.v("Received: " + data); JSONObject request = new JSONObject(data); int id = request.getInt("id"); String method = request.getString("method"); JSONArray params = request.getJSONArray("params"); MethodDescriptor rpc = mReceiverManager.getMethodDescriptor(method); if (rpc == null) { return JsonRpcResult.error(id, new RpcError("Unknown RPC.")).toString(); } try { return JsonRpcResult.result(id, rpc.invoke(mReceiverManager, params)).toString(); } catch (Throwable t) { Log.e("Invocation error.", t); return JsonRpcResult.error(id, t).toString(); } } @SuppressWarnings("unused") public void dismiss() { Activity parent = getActivity(); parent.finish(); } } private class HtmlEventObserver implements EventFacade.EventObserver { private Map<String, Set<Integer>> mEventMap = new HashMap<String, Set<Integer>>(); public void register(String eventName, Integer id) { if (mEventMap.containsKey(eventName)) { mEventMap.get(eventName).add(id); } else { Set<Integer> idSet = new HashSet<Integer>(); idSet.add(id); mEventMap.put(eventName, idSet); } } public void onEventReceived(Event event) { final JSONObject json = new JSONObject(); try { json.put("data", JsonBuilder.build(event.getData())); } catch (JSONException e) { Log.e(e); } if (mEventMap.containsKey(event.getName())) { for (final Integer id : mEventMap.get(event.getName())) { getActivity().runOnUiThread(new Runnable() { public void run() { mView.loadUrl(String.format("javascript:droid._callback(%d, %s);", id, json)); } }); } } } @SuppressWarnings("unused") public void dismiss() { Activity parent = getActivity(); parent.finish(); } } private class ChromeClient extends WebChromeClient { private final static String JS_TITLE = "JavaScript Dialog"; private final Activity mActivity; private final Resources mResources; private final ExecutorService mmExecutor; public ChromeClient(Activity activity) { mActivity = activity; mResources = mActivity.getResources(); mmExecutor = new SingleThreadExecutor(); } @Override public void onReceivedTitle(WebView view, String title) { mActivity.setTitle(title); } @Override public void onReceivedIcon(WebView view, Bitmap icon) { mActivity.getWindow().requestFeature(Window.FEATURE_RIGHT_ICON); mActivity.getWindow().setFeatureDrawable(Window.FEATURE_RIGHT_ICON, new BitmapDrawable(icon)); } @Override public boolean onJsAlert(WebView view, String url, String message, final JsResult result) { final UiFacade uiFacade = mReceiverManager.getReceiver(UiFacade.class); uiFacade.dialogCreateAlert(JS_TITLE, message); uiFacade.dialogSetPositiveButtonText(mResources.getString(android.R.string.ok)); mmExecutor.execute(new Runnable() { public void run() { try { uiFacade.dialogShow(); } catch (InterruptedException e) { throw new RuntimeException(e); } uiFacade.dialogGetResponse(); result.confirm(); } }); return true; } @SuppressWarnings("unchecked") @Override public boolean onJsConfirm(WebView view, String url, String message, final JsResult result) { final UiFacade uiFacade = mReceiverManager.getReceiver(UiFacade.class); uiFacade.dialogCreateAlert(JS_TITLE, message); uiFacade.dialogSetPositiveButtonText(mResources.getString(android.R.string.ok)); uiFacade.dialogSetNegativeButtonText(mResources.getString(android.R.string.cancel)); mmExecutor.execute(new Runnable() { public void run() { try { uiFacade.dialogShow(); } catch (InterruptedException e) { throw new RuntimeException(e); } Map<String, Object> mResultMap = (Map<String, Object>) uiFacade.dialogGetResponse(); if ("positive".equals(mResultMap.get("which"))) { result.confirm(); } else { result.cancel(); } } }); return true; } @Override public boolean onJsPrompt(WebView view, String url, final String message, final String defaultValue, final JsPromptResult result) { final UiFacade uiFacade = mReceiverManager.getReceiver(UiFacade.class); mmExecutor.execute(new Runnable() { public void run() { String value = null; try { value = uiFacade.dialogGetInput(JS_TITLE, message, defaultValue); } catch (InterruptedException e) { throw new RuntimeException(e); } if (value != null) { result.confirm(value); } else { result.cancel(); } } }); return true; } } }