Android WebViews

本文演示了如何在大型 Android 应用里面，内嵌 Cordova-enabled WebView 组件。欲了解组件之间如何交互，参见插件开发指南。

若你对 Android 还不熟悉，可以先参考Android 平台，并安装 Android SDK。 Cordova 1.9 开始, Android 平台依赖CordovaWebView 组件,该组件是基于 CordovaActivity组件构建的。

1. 首先确保有最新的 Cordova 的发布包，从 cordova.apache.org 下载，并解压 Android 包。

2. 切换到 Android 包的 /framework 目录，并运行 ant jar，它将创建 Cordova .jar 文件，格式如 /framework/cordova-x.x.x.jar

3. 拷贝 .jar 文件到 Android 项目的/libs 目录

4. 添加如下 /res/xml/main.xml 文件,设置相应的 layout_height, layout_width 和 id:

    <org.apache.cordova.CordovaWebView
        android:id="@+id/tutorialView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
   

5. 修改 activity 让其实现 CordovaInterface，它会实现包含的方法。可以拷贝自 /framework/src/org/apache/cordova/CordovaActivity.java, 或者自己实现。下面的代码片段显示，依赖于接口上的基本应用。请注意引用视图 id 与上面显示的 XML 片段指定的id属性如何相匹配:

    public class CordovaViewTestActivity extends Activity implements CordovaInterface {
        CordovaWebView cwv;
        /* Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            cwv = (CordovaWebView) findViewById(R.id.tutorialView);
            Config.init(this);
            cwv.loadUrl(Config.getStartUrl());
        }
   

6. 若应用使用了摄像头，用法如下:

    @Override
    public void setActivityResultCallback(CordovaPlugin plugin) {
        this.activityResultCallback = plugin;
    }
    /**
     * Launch an activity for which you would like a result when it finished. When this activity exits,
     * your onActivityResult() method is called.
     *
     * @param command           The command object
     * @param intent            The intent to start
     * @param requestCode       The request code that is passed to callback to identify the activity
     */
    public void startActivityForResult(CordovaPlugin command, Intent intent, int requestCode) {
        this.activityResultCallback = command;
        this.activityResultKeepRunning = this.keepRunning;
   
        // If multitasking turned on, then disable it for activities that return results
        if (command != null) {
            this.keepRunning = false;
        }
   
        // Start activity
        super.startActivityForResult(intent, requestCode);
    }   
   
    @Override
    /**
     * Called when an activity you launched exits, giving you the requestCode you started it with,
     * the resultCode it returned, and any additional data from it.
     *
     * @param requestCode       The request code originally supplied to startActivityForResult(),
     *                          allowing you to identify who this result came from.
     * @param resultCode        The integer result code returned by the child activity through its setResult().
     * @param data              An Intent, which can return result data to the caller (various data can be attached to Intent "extras").
     */
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
        super.onActivityResult(requestCode, resultCode, intent);
        CordovaPlugin callback = this.activityResultCallback;
        if (callback != null) {
            callback.onActivityResult(requestCode, resultCode, intent);
        }
    }
   

7. 最后，添加线程池，除非插件没有线程来运行:

    @Override
    public ExecutorService getThreadPool() {
        return threadPool;
    }
   

8. 拷贝应用的 HTML 和 JavaScript 文件到 Android 项目的 /assets/www 目录

9. 从 /framework/res/xml 拷贝 config.xml 文件到 /res/xml 目录