Java tutorial
/** * Copyright (c) 2015-present, Facebook, Inc. * All rights reserved. * * This source code is licensed under the BSD-style license found in the * LICENSE file in the root directory of this source tree. An additional grant * of patent rights can be found in the PATENTS file in the same directory. */ package com.phxrb.CWebView; import android.annotation.SuppressLint; import android.content.ActivityNotFoundException; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.Picture; import android.net.Uri; import android.os.Build; import android.text.TextUtils; import android.view.ViewGroup.LayoutParams; import android.webkit.ConsoleMessage; import android.webkit.CookieManager; import android.webkit.GeolocationPermissions; import android.webkit.JavascriptInterface; import android.webkit.JsResult; import android.webkit.ValueCallback; import android.webkit.WebChromeClient; import android.webkit.WebSettings; import android.webkit.WebView; import android.webkit.WebViewClient; import com.facebook.common.logging.FLog; import com.facebook.react.bridge.Arguments; import com.facebook.react.bridge.LifecycleEventListener; import com.facebook.react.bridge.ReactContext; import com.facebook.react.bridge.ReadableArray; import com.facebook.react.bridge.ReadableMap; import com.facebook.react.bridge.ReadableMapKeySetIterator; import com.facebook.react.bridge.WritableMap; import com.facebook.react.common.MapBuilder; import com.facebook.react.common.ReactConstants; import com.facebook.react.common.build.ReactBuildConfig; import com.facebook.react.module.annotations.ReactModule; import com.facebook.react.uimanager.SimpleViewManager; import com.facebook.react.uimanager.ThemedReactContext; import com.facebook.react.uimanager.UIManagerModule; import com.facebook.react.uimanager.annotations.ReactProp; import com.facebook.react.uimanager.events.ContentSizeChangeEvent; import com.facebook.react.uimanager.events.Event; import com.facebook.react.uimanager.events.EventDispatcher; import com.facebook.react.views.webview.WebViewConfig; import com.facebook.react.views.webview.events.TopLoadingErrorEvent; import com.facebook.react.views.webview.events.TopLoadingFinishEvent; import com.facebook.react.views.webview.events.TopLoadingStartEvent; import com.facebook.react.views.webview.events.TopMessageEvent; import org.json.JSONException; import org.json.JSONObject; import java.io.UnsupportedEncodingException; import java.util.HashMap; import java.util.Locale; import java.util.Map; import javax.annotation.Nullable; /** * Manages instances of {@link WebView} * * Can accept following commands: * - GO_BACK * - GO_FORWARD * - RELOAD * * {@link WebView} instances could emit following direct events: * - topLoadingFinish * - topLoadingStart * - topLoadingError * * Each event will carry the following properties: * - target - view's react tag * - url - url set for the webview * - loading - whether webview is in a loading state * - title - title of the current page * - canGoBack - boolean, whether there is anything on a history stack to go back * - canGoForward - boolean, whether it is possible to request GO_FORWARD command */ @ReactModule(name = RNWebViewManager.REACT_CLASS) public class RNWebViewManager extends SimpleViewManager<WebView> { protected static final String REACT_CLASS = "RCTWebViewAndroid"; private static final String HTML_ENCODING = "UTF-8"; private static final String HTML_MIME_TYPE = "text/html; charset=utf-8"; private static final String BRIDGE_NAME = "__REACT_WEB_VIEW_BRIDGE"; private static final String HTTP_METHOD_POST = "POST"; public static final int COMMAND_GO_BACK = 1; public static final int COMMAND_GO_FORWARD = 2; public static final int COMMAND_RELOAD = 3; public static final int COMMAND_STOP_LOADING = 4; public static final int COMMAND_POST_MESSAGE = 5; public static final int COMMAND_INJECT_JAVASCRIPT = 6; private RNWebViewPackage aPackage; // Use `webView.loadUrl("about:blank")` to reliably reset the view // state and release page resources (including any running JavaScript). private static final String BLANK_URL = "about:blank"; private WebViewConfig mWebViewConfig; private @Nullable WebView.PictureListener mPictureListener; protected static class ReactWebViewClient extends WebViewClient { private boolean mLastLoadFailed = false; @Override public void onPageFinished(WebView webView, String url) { super.onPageFinished(webView, url); if (!mLastLoadFailed) { ReactWebView reactWebView = (ReactWebView) webView; reactWebView.callInjectedJavaScript(); reactWebView.linkBridge(); emitFinishEvent(webView, url); } } @Override public void onPageStarted(WebView webView, String url, Bitmap favicon) { super.onPageStarted(webView, url, favicon); mLastLoadFailed = false; dispatchEvent(webView, new TopLoadingStartEvent(webView.getId(), createWebViewEvent(webView, url))); } @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { if (url.startsWith("http://") || url.startsWith("https://") || url.startsWith("file://") || url.equals("about:blank")) { return false; } else { try { Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url)); intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); view.getContext().startActivity(intent); } catch (ActivityNotFoundException e) { FLog.w(ReactConstants.TAG, "activity not found to handle uri scheme for: " + url, e); } return true; } } @Override public void onReceivedError(WebView webView, int errorCode, String description, String failingUrl) { super.onReceivedError(webView, errorCode, description, failingUrl); mLastLoadFailed = true; // In case of an error JS side expect to get a finish event first, and then get an error event // Android WebView does it in the opposite way, so we need to simulate that behavior emitFinishEvent(webView, failingUrl); WritableMap eventData = createWebViewEvent(webView, failingUrl); eventData.putDouble("code", errorCode); eventData.putString("description", description); dispatchEvent(webView, new TopLoadingErrorEvent(webView.getId(), eventData)); } @Override public void doUpdateVisitedHistory(WebView webView, String url, boolean isReload) { super.doUpdateVisitedHistory(webView, url, isReload); dispatchEvent(webView, new TopLoadingStartEvent(webView.getId(), createWebViewEvent(webView, url))); } private void emitFinishEvent(WebView webView, String url) { dispatchEvent(webView, new TopLoadingFinishEvent(webView.getId(), createWebViewEvent(webView, url))); } private WritableMap createWebViewEvent(WebView webView, String url) { WritableMap event = Arguments.createMap(); event.putDouble("target", webView.getId()); // Don't use webView.getUrl() here, the URL isn't updated to the new value yet in callbacks // like onPageFinished event.putString("url", url); event.putBoolean("loading", !mLastLoadFailed && webView.getProgress() != 100); event.putString("title", webView.getTitle()); event.putBoolean("canGoBack", webView.canGoBack()); event.putBoolean("canGoForward", webView.canGoForward()); return event; } } /** * Subclass of {@link WebView} that implements {@link LifecycleEventListener} interface in order * to call {@link WebView#destroy} on activty destroy event and also to clear the client */ protected static class ReactWebView extends WebView implements LifecycleEventListener { private @Nullable String injectedJS; private boolean messagingEnabled = false; private class ReactWebViewBridge { ReactWebView mContext; ReactWebViewBridge(ReactWebView c) { mContext = c; } @JavascriptInterface public void postMessage(String message) { mContext.onMessage(message); } } /** * WebView must be created with an context createViewInstanceof the current activity * * Activity Context is required for creation of dialogs internally by WebView * Reactive Native needed for access to ReactNative internal system functionality * */ public ReactWebView(ThemedReactContext reactContext) { super(reactContext); } @Override public void onHostResume() { // do nothing } @Override public void onHostPause() { // do nothing } @Override public void onHostDestroy() { cleanupCallbacksAndDestroy(); } public void setInjectedJavaScript(@Nullable String js) { injectedJS = js; } public void setMessagingEnabled(boolean enabled) { if (messagingEnabled == enabled) { return; } messagingEnabled = enabled; if (enabled) { addJavascriptInterface(new ReactWebViewBridge(this), BRIDGE_NAME); linkBridge(); } else { removeJavascriptInterface(BRIDGE_NAME); } } public void callInjectedJavaScript() { if (getSettings().getJavaScriptEnabled() && injectedJS != null && !TextUtils.isEmpty(injectedJS)) { loadUrl("javascript:(function() {\n" + injectedJS + ";\n})();"); } } public void linkBridge() { if (messagingEnabled) { if (ReactBuildConfig.DEBUG && Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) { // See isNative in lodash String testPostMessageNative = "String(window.postMessage) === String(Object.hasOwnProperty).replace('hasOwnProperty', 'postMessage')"; evaluateJavascript(testPostMessageNative, new ValueCallback<String>() { @Override public void onReceiveValue(String value) { if (value.equals("true")) { FLog.w(ReactConstants.TAG, "Setting onMessage on a WebView overrides existing values of window.postMessage, but a previous value was defined"); } } }); } loadUrl("javascript:(" + "window.originalPostMessage = window.postMessage," + "window.postMessage = function(data) {" + BRIDGE_NAME + ".postMessage(String(data));" + "}" + ")"); } } public void onMessage(String message) { dispatchEvent(this, new TopMessageEvent(this.getId(), message)); } private void cleanupCallbacksAndDestroy() { setWebViewClient(null); destroy(); } } public RNWebViewManager() { mWebViewConfig = new WebViewConfig() { public void configWebView(WebView webView) { } }; } public RNWebViewManager(WebViewConfig webViewConfig) { mWebViewConfig = webViewConfig; } @Override public String getName() { return REACT_CLASS; } @Override protected WebView createViewInstance(ThemedReactContext reactContext) { ReactWebView webView = new ReactWebView(reactContext); webView.getSettings().setAllowFileAccess(true); webView.setWebChromeClient(new WebChromeClient() { @Override public boolean onConsoleMessage(ConsoleMessage message) { if (ReactBuildConfig.DEBUG) { return super.onConsoleMessage(message); } // Ignore console logs in non debug builds. return true; } @Override public void onGeolocationPermissionsShowPrompt(String origin, GeolocationPermissions.Callback callback) { callback.invoke(origin, true, false); } @Override public boolean onJsAlert(WebView view, String url, String message, JsResult result) { getPackage().getModule().showAlert(url, message, result); return true; } @SuppressWarnings("unused") public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) { getPackage().getModule().startFileChooserIntent(uploadMsg, acceptType); } // For Android 5.0+ @Override @SuppressLint("NewApi") public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) { return getPackage().getModule().startFileChooserIntent(filePathCallback, fileChooserParams.createIntent()); } }); reactContext.addLifecycleEventListener(webView); mWebViewConfig.configWebView(webView); webView.getSettings().setBuiltInZoomControls(true); webView.getSettings().setDisplayZoomControls(false); webView.getSettings().setDomStorageEnabled(true); // Fixes broken full-screen modals/galleries due to body height being 0. webView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); if (ReactBuildConfig.DEBUG && Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) { WebView.setWebContentsDebuggingEnabled(true); } return webView; } @ReactProp(name = "javaScriptEnabled") public void setJavaScriptEnabled(WebView view, boolean enabled) { view.getSettings().setJavaScriptEnabled(enabled); } // @ReactProp(name = "thirdPartyCookiesEnabled") // public void setThirdPartyCookiesEnabled(WebView view, boolean enabled) { // if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { // CookieManager.getInstance().setAcceptThirdPartyCookies(view, enabled); // } // } @ReactProp(name = "scalesPageToFit") public void setScalesPageToFit(WebView view, boolean enabled) { view.getSettings().setUseWideViewPort(!enabled); } @ReactProp(name = "domStorageEnabled") public void setDomStorageEnabled(WebView view, boolean enabled) { view.getSettings().setDomStorageEnabled(enabled); } @ReactProp(name = "userAgent") public void setUserAgent(WebView view, @Nullable String userAgent) { if (userAgent != null) { // TODO(8496850): Fix incorrect behavior when property is unset (uA == null) view.getSettings().setUserAgentString(userAgent); } } @ReactProp(name = "mediaPlaybackRequiresUserAction") public void setMediaPlaybackRequiresUserAction(WebView view, boolean requires) { view.getSettings().setMediaPlaybackRequiresUserGesture(requires); } @ReactProp(name = "allowUniversalAccessFromFileURLs") public void setAllowUniversalAccessFromFileURLs(WebView view, boolean allow) { view.getSettings().setAllowUniversalAccessFromFileURLs(allow); } // @ReactProp(name = "saveFormDataDisabled") // public void setSaveFormDataDisabled(WebView view, boolean disable) { // view.getSettings().setSaveFormData(!disable); // } @ReactProp(name = "injectedJavaScript") public void setInjectedJavaScript(WebView view, @Nullable String injectedJavaScript) { ((ReactWebView) view).setInjectedJavaScript(injectedJavaScript); } @ReactProp(name = "messagingEnabled") public void setMessagingEnabled(WebView view, boolean enabled) { ((ReactWebView) view).setMessagingEnabled(enabled); } @ReactProp(name = "source") public void setSource(WebView view, @Nullable ReadableMap source) { if (source != null) { if (source.hasKey("html")) { String html = source.getString("html"); if (source.hasKey("baseUrl")) { view.loadDataWithBaseURL(source.getString("baseUrl"), html, HTML_MIME_TYPE, HTML_ENCODING, null); } else { view.loadData(html, HTML_MIME_TYPE, HTML_ENCODING); } return; } if (source.hasKey("uri")) { String url = source.getString("uri"); String previousUrl = view.getUrl(); if (previousUrl != null && previousUrl.equals(url)) { return; } if (source.hasKey("method")) { String method = source.getString("method"); if (method.equals(HTTP_METHOD_POST)) { byte[] postData = null; if (source.hasKey("body")) { String body = source.getString("body"); try { postData = body.getBytes("UTF-8"); } catch (UnsupportedEncodingException e) { postData = body.getBytes(); } } if (postData == null) { postData = new byte[0]; } view.postUrl(url, postData); return; } } HashMap<String, String> headerMap = new HashMap<>(); if (source.hasKey("headers")) { ReadableMap headers = source.getMap("headers"); ReadableMapKeySetIterator iter = headers.keySetIterator(); while (iter.hasNextKey()) { String key = iter.nextKey(); if ("user-agent".equals(key.toLowerCase(Locale.ENGLISH))) { if (view.getSettings() != null) { view.getSettings().setUserAgentString(headers.getString(key)); } } else { headerMap.put(key, headers.getString(key)); } } } view.loadUrl(url, headerMap); return; } } view.loadUrl(BLANK_URL); } @ReactProp(name = "onContentSizeChange") public void setOnContentSizeChange(WebView view, boolean sendContentSizeChangeEvents) { if (sendContentSizeChangeEvents) { view.setPictureListener(getPictureListener()); } else { view.setPictureListener(null); } } // @ReactProp(name = "mixedContentMode") // public void setMixedContentMode(WebView view, @Nullable String mixedContentMode) { // if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { // if (mixedContentMode == null || "never".equals(mixedContentMode)) { // view.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_NEVER_ALLOW); // } else if ("always".equals(mixedContentMode)) { // view.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW); // } else if ("compatibility".equals(mixedContentMode)) { // view.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_COMPATIBILITY_MODE); // } // } // } @Override protected void addEventEmitters(ThemedReactContext reactContext, WebView view) { // Do not register default touch emitter and let WebView implementation handle touches view.setWebViewClient(new ReactWebViewClient()); } @Override public @Nullable Map<String, Integer> getCommandsMap() { return MapBuilder.of("goBack", COMMAND_GO_BACK, "goForward", COMMAND_GO_FORWARD, "reload", COMMAND_RELOAD, "stopLoading", COMMAND_STOP_LOADING, "postMessage", COMMAND_POST_MESSAGE, "injectJavaScript", COMMAND_INJECT_JAVASCRIPT); } @Override public void receiveCommand(WebView root, int commandId, @Nullable ReadableArray args) { switch (commandId) { case COMMAND_GO_BACK: root.goBack(); break; case COMMAND_GO_FORWARD: root.goForward(); break; case COMMAND_RELOAD: root.reload(); break; case COMMAND_STOP_LOADING: root.stopLoading(); break; case COMMAND_POST_MESSAGE: try { JSONObject eventInitDict = new JSONObject(); eventInitDict.put("data", args.getString(0)); root.loadUrl("javascript:(function () {" + "var event;" + "var data = " + eventInitDict.toString() + ";" + "try {" + "event = new MessageEvent('message', data);" + "} catch (e) {" + "event = document.createEvent('MessageEvent');" + "event.initMessageEvent('message', true, true, data.data, data.origin, data.lastEventId, data.source);" + "}" + "document.dispatchEvent(event);" + "})();"); } catch (JSONException e) { throw new RuntimeException(e); } break; case COMMAND_INJECT_JAVASCRIPT: root.loadUrl("javascript:" + args.getString(0)); break; } } @Override public void onDropViewInstance(WebView webView) { super.onDropViewInstance(webView); ((ThemedReactContext) webView.getContext()).removeLifecycleEventListener((ReactWebView) webView); ((ReactWebView) webView).cleanupCallbacksAndDestroy(); } private WebView.PictureListener getPictureListener() { if (mPictureListener == null) { mPictureListener = new WebView.PictureListener() { @Override public void onNewPicture(WebView webView, Picture picture) { dispatchEvent(webView, new ContentSizeChangeEvent(webView.getId(), webView.getWidth(), webView.getContentHeight())); } }; } return mPictureListener; } private static void dispatchEvent(WebView webView, Event event) { ReactContext reactContext = (ReactContext) webView.getContext(); EventDispatcher eventDispatcher = reactContext.getNativeModule(UIManagerModule.class).getEventDispatcher(); eventDispatcher.dispatchEvent(event); } public void setPackage(RNWebViewPackage aPackage) { this.aPackage = aPackage; } public RNWebViewPackage getPackage() { return this.aPackage; } }