android.webkit.WebView#getContext ( )源码实例Demo

/**
 * 系统弹出提示框
 *
 * @param webView 浏览器
 * @param message 提示信息
 */
public static void alert(WebView webView, String message) {
    // 构建一个Builder来显示网页中的alert对话框
    AlertDialog.Builder builder = new AlertDialog.Builder(webView.getContext());
    builder.setTitle(webView.getContext().getString(R.string.dialog_title_system_msg));
    builder.setMessage(message);
    builder.setPositiveButton(android.R.string.ok, new AlertDialog.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.dismiss();
        }
    });
    builder.setCancelable(false);
    builder.create();
    builder.show();
}
 

/**
 * 系统弹出提示框
 *
 * @param webView 浏览器
 * @param message 提示信息
 */
public static void alert(WebView webView, String message) {
    // 构建一个Builder来显示网页中的alert对话框
    AlertDialog.Builder builder = new AlertDialog.Builder(webView.getContext());
    builder.setTitle(webView.getContext().getString(R.string.dialog_title_system_msg));
    builder.setMessage(message);
    builder.setPositiveButton(android.R.string.ok, new AlertDialog.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            dialog.dismiss();
        }
    });
    builder.setCancelable(false);
    builder.create();
    builder.show();
}
 

@Override
public void onReceivedTitle(WebView view, String title) {
    super.onReceivedTitle(view, title);
    if (TextUtils.isEmpty(title)) {
        return;
    }
    Matcher matcher = Patterns.WEB_URL.matcher(title);
    if (matcher.matches()) {
        return;
    }
    // 部分系统会优先用页面的location作为title，这种情况需要过滤掉
    if (Patterns.WEB_URL.matcher(title).matches()) {
        return;
    }
    // Hack：过滤掉rexxar页面
    if (title.contains(".html?uri=")) {
        return;
    }
    // 设置title
    if (view.getContext() instanceof Activity) {
        ((Activity) view.getContext()).setTitle(Uri.decode(title));
    }
}
 

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private WebResourceResponse handleImageRequest(final WebView aWebView, final String aUrl, String strMimeType)
{
    KCWebView webView = (KCWebView) aWebView;
    if (mImageDownloader == null)
        mImageDownloader = new KCWebImageDownloader(aWebView.getContext(), webView.getWebPath());
    if (mWebImageHandler==null)
        mWebImageHandler = new KCWebImageHandler(mWebImageListener);

    KCWebImage webImage = mImageDownloader.downloadImageFile(aUrl, mWebImageHandler.add(aUrl));
    InputStream stream = webImage.getInputStream();
    if (stream == null)
    {
        Log.e("image", "current stream is null,download image from net");
        return null;
    }
    return new WebResourceResponse(strMimeType, "utf-8", stream);
}
 

@Override
public boolean onJsAlert(WebView view, String url, String message, final JsResult result) {
    if (!((EBrowserActivity) view.getContext()).isVisable()) {
        result.confirm();
    }
    AlertDialog.Builder dia = new AlertDialog.Builder(view.getContext());
    dia.setTitle(EUExUtil.getResStringID("prompt"));
    dia.setMessage(message);
    dia.setCancelable(false);
    dia.setPositiveButton(EUExUtil.getResStringID("confirm"), new OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            result.confirm();
        }
    });
    dia.create();
    dia.show();
    return true;
}
 

public static void loadWebapp(WebView webView, AppSettings appSettings, boolean doLogin) {
    Context context = webView.getContext();
    Uri url;
    try {
        url = Uri.parse(appSettings.getProfilePathFull());
    } catch (Exception e) {
        webView.loadData(context.getString(R.string.no_valid_path), "text/html", "UTF-16");
        return;
    }

    String url_s = url.toString();
    if (appSettings.isProfileEmpty()) {
        webView.loadData(context.getString(R.string.no_valid_path), "text/html", "UTF-16");
    } else {
        webView.loadUrl(url_s);
        if (doLogin) {
            url_s += "?a=checklogin";
            String postData = "name=" + appSettings.getProfileLoginUsername() + "&password=" + appSettings.getProfileLoginPassword();
            webView.postUrl(url_s, EncodingUtils.getBytes(postData, "base64"));
        }
    }
}
 

private static void callMayDeepLink(WebView webView, Uri uri) {
    boolean mayDeepLink;
    String cb = uri.getQueryParameter("cb");
    String urlParam = uri.getQueryParameter("url");

    if ((webView.getContext() == null)
            || (webView.getContext().getPackageManager() == null)
            || (urlParam == null)) {
        mayDeepLink = false;
    } else {
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(Uri.decode(urlParam)));
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        mayDeepLink = intent.resolveActivity(webView.getContext().getPackageManager()) != null;
    }

    LinkedList<Pair<String, String>> list = new LinkedList<Pair<String, String>>();
    list.add(new Pair(KEY_CALLER, CALL_MAYDEEPLINK));
    list.add(new Pair("mayDeepLink", String.valueOf(mayDeepLink)));
    loadResult(webView, cb, list);
}
 

private static void callDeepLink(WebView webView, Uri uri) {
    String cb = uri.getQueryParameter("cb");
    String urlParam = uri.getQueryParameter("url");

    LinkedList<Pair<String, String>> list = new LinkedList<Pair<String, String>>();
    list.add(new Pair(KEY_CALLER, CALL_DEEPLINK));

    if ((webView.getContext() == null)
            || (urlParam == null)) {
        loadResult(webView, cb, list);
        return;
    }
    try {
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(Uri.decode(urlParam)));
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        webView.getContext().startActivity(intent);
    } catch (ActivityNotFoundException e) {
        loadResult(webView, cb, list);
    }
}
 

private static void callExternalBrowser(WebView webView, Uri uri) {
    String urlParam = uri.getQueryParameter("url");

    if ((webView.getContext() == null)
            || (urlParam == null)
            || (!urlParam.startsWith("http"))) {
        return;
    }
    try {
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(Uri.decode(urlParam)));
        webView.getContext().startActivity(intent);
    } catch (ActivityNotFoundException e) {
        Toast.makeText(webView.getContext(),
                R.string.action_cant_be_completed,
                Toast.LENGTH_SHORT).show();
    }
}
 

@Override
public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
    AlertDialog.Builder builder = new AlertDialog.Builder(view.getContext());
    builder.setTitle("注意").setMessage(message).setPositiveButton("确定", null);
    builder.setCancelable(false);
    AlertDialog dialog = builder.create();
    dialog.show();
    result.confirm();
    return true;
}
 

@Override
public boolean handle(WebView view, String url) {
    if (TextUtils.isEmpty(url)) {
        return false;
    }
    Uri uri = Uri.parse(url);
    if (TextUtils.equals(uri.getPath(), getPath())) {
        String title = uri.getQueryParameter(KEY_TITLE);
        if (null != view && view.getContext() instanceof Activity) {
            ((Activity)view.getContext()).setTitle(Uri.decode(title));
        }
        return true;
    }
    return false;
}
 

@Override
public void injectJsBridge(WebView webView,String JsName) {
    webView.loadUrl("javascript:" + PopUtils.getJsCode(webView.getContext(),JsName));
    mContext=webView.getContext();
    Log.d(POP_TAG,"注入JSBrige成功");
}
 

/**
 * 结束当前窗口
 *
 * @param view 浏览器
 */
public static void goBack(WebView view) {
    if (view.getContext() instanceof Activity) {
        ((Activity) view.getContext()).finish();
    }
}
 

/**
 * 结束当前窗口
 *
 * @param view 浏览器
 */
public static void goBack(WebView view) {
    if (view.getContext() instanceof Activity) {
        ((Activity) view.getContext()).finish();
    }
}
 

@Override
public boolean shouldOverrideUrlLoading(final WebView view, final String url) {
    if (url.equals("file:///android_asset/" + LocalizedContent.licensesUrl)) {
        final Context context = view.getContext();

        context.startActivity(new Intent(context, OssLicensesMenuActivity.class));
        return true;
    }

    // If this is an internal URL like focus:about then we load the content ourselves here.
    if (LocalizedContent.handleInternalContent(url, view)) {
        return true;
    }

    // Allow pages to blank themselves by loading about:blank. While it's a little incorrect to let pages
    // access our internal URLs, Chrome allows loads to about:blank and, to ensure our behavior conforms
    // to the behavior that most of the web is developed against, we do too.
    if (url.equals(URLs.ABOUT_BLANK.toString())) {
        return false;
    }

    // shouldOverrideUrlLoading() is called for both the main frame, and iframes.
    // That can get problematic if an iframe tries to load an unsupported URL.
    // We then try to either handle that URL (ask to open relevant app), or extract
    // a fallback URL from the intent (or worst case fall back to an error page). In the
    // latter 2 cases, we explicitly open the fallback/error page in the main view.
    // Websites probably shouldn't use unsupported URLs in iframes, but we do need to
    // be careful to handle all valid schemes here to avoid redirecting due to such an iframe
    // (e.g. we don't want to redirect to a data: URI just because an iframe shows such
    // a URI).
    // (The API 24+ version of shouldOverrideUrlLoading() lets us determine whether
    // the request is for the main frame, and if it's not we could then completely
    // skip the external URL handling.)
    final Uri uri = Uri.parse(url);
    if (!UrlUtils.isSupportedProtocol(uri.getScheme()) &&
            callback != null &&
            IntentUtils.handleExternalUri(view.getContext(), (IWebView) view, url)) {
        return true;
    }

    return super.shouldOverrideUrlLoading(view, url);
}
 

protected static void dispatchEvent(WebView webView, Event event) {
    ReactContext reactContext = (ReactContext) webView.getContext();
    EventDispatcher eventDispatcher =
            reactContext.getNativeModule(UIManagerModule.class).getEventDispatcher();
    eventDispatcher.dispatchEvent(event);
}
 

protected static void dispatchEvent(WebView webView, Event event) {
  ReactContext reactContext = (ReactContext) webView.getContext();
  EventDispatcher eventDispatcher =
    reactContext.getNativeModule(UIManagerModule.class).getEventDispatcher();
  eventDispatcher.dispatchEvent(event);
}
 

private void settings(WebView webView) {
    mWebSettings = webView.getSettings();
    mWebSettings.setJavaScriptEnabled(true);
    mWebSettings.setSupportZoom(true);
    mWebSettings.setBuiltInZoomControls(false);
    mWebSettings.setSavePassword(false);
    if (AgentWebUtils.checkNetwork(webView.getContext())) {
        //根据cache-control获取数据。
        mWebSettings.setCacheMode(WebSettings.LOAD_DEFAULT);
    } else {
        //没网，则从本地获取，即离线加载
        mWebSettings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
    }
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
        //适配5.0不允许http和https混合使用情况
        mWebSettings.setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW);
        webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
    } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
        webView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
    } else if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
        webView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
    }
    mWebSettings.setTextZoom(100);
    mWebSettings.setDatabaseEnabled(true);
    mWebSettings.setAppCacheEnabled(true);
    mWebSettings.setLoadsImagesAutomatically(true);
    mWebSettings.setSupportMultipleWindows(false);
    // 是否阻塞加载网络图片  协议http or https
    mWebSettings.setBlockNetworkImage(false);
    // 允许加载本地文件html  file协议
    mWebSettings.setAllowFileAccess(true);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
        // 通过 file url 加载的 Javascript 读取其他的本地文件 .建议关闭
        mWebSettings.setAllowFileAccessFromFileURLs(false);
        // 允许通过 file url 加载的 Javascript 可以访问其他的源，包括其他的文件和 http，https 等其他的源
        mWebSettings.setAllowUniversalAccessFromFileURLs(false);
    }
    mWebSettings.setJavaScriptCanOpenWindowsAutomatically(true);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {

        mWebSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
    } else {
        mWebSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.NORMAL);
    }
    mWebSettings.setLoadWithOverviewMode(false);
    mWebSettings.setUseWideViewPort(false);
    mWebSettings.setDomStorageEnabled(true);
    mWebSettings.setNeedInitialFocus(true);
    mWebSettings.setDefaultTextEncodingName("utf-8");//设置编码格式
    mWebSettings.setDefaultFontSize(16);
    mWebSettings.setMinimumFontSize(12);//设置 WebView 支持的最小字体大小，默认为 8
    mWebSettings.setGeolocationEnabled(true);
    String dir = AgentWebConfig.getCachePath(webView.getContext());
    LogUtils.i(TAG, "dir:" + dir + "   appcache:" + AgentWebConfig.getCachePath(webView.getContext()));
    //设置数据库路径  api19 已经废弃,这里只针对 webkit 起作用
    mWebSettings.setGeolocationDatabasePath(dir);
    mWebSettings.setDatabasePath(dir);
    mWebSettings.setAppCachePath(dir);
    //缓存文件最大值
    mWebSettings.setAppCacheMaxSize(Long.MAX_VALUE);
    mWebSettings.setUserAgentString(getWebSettings()
            .getUserAgentString()
            .concat(USERAGENT_AGENTWEB)
            .concat(USERAGENT_UC)
    );
    LogUtils.i(TAG, "UserAgentString : " + mWebSettings.getUserAgentString());
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
        // 安卓9.0后不允许多进程使用同一个数据目录，需设置前缀来区分
        // 参阅 https://blog.csdn.net/lvshuchangyin/article/details/89446629
        Context context = webView.getContext();
        String processName = ProcessUtils.getCurrentProcessName(context);
        if (!context.getApplicationContext().getPackageName().equals(processName)) {
            WebView.setDataDirectorySuffix(processName);
        }
    }
}