Does WebView saveState() preserve Javascript variables/environment?

Question

I\'ve searched many threads and still cannot find the answer to my question. I\'m working on an Android app which uses WebView.

I use

Answer 1

As user2113581 commented, moving the WebView into a context of the application rather than the Activity is a potential solution. This still has all of the pitfalls that user2113581 mentioned, including <select> not working (because it creates a window, but an application context does not have a window token).

I have extended my Application to manage my webview...

MyApplication.java:

public class MyApplication extends Application {
  private WebView mWebView;
  private boolean mWebViewInitialized;
  // ...

  @Override public void onCreate() {
    super.onCreate();
    mWebView = new WebView(this);
    mWebViewInitialized = false; // we do some initialization once in our activity.
  }

  public WebView getWebView() { return mWebView; }
  public boolean isWebViewInitialized() { return mWebViewInitialized; }
  public void setWebViewInitialized(boolean initialized) {
    mWebViewInitialized = initialized;
  }
}

In our activity:

@Override protected void onCreate(Bundle savedInstanceState) {
  // ...
  MyApplication app = (MyApplication) getApplication();
  mWebView = app.getWebView();
  if (!app.isWebViewInitialized()) { 
    /* first time initialization */ 
    app.setWebViewInitialized(true);
  }
}

Finally, in your Activity, you will want to add the mWebView to a container view (FrameLayout, or similar) during a lifecycle event that makes sense. You'll need to remove it from the container when the activity is being paused or stopped. I've used onResume and onPause with good results.

Answer 2

Very few information found, only this line:

Please note that this method no longer stores the display data for this WebView. The previous behavior could potentially leak files if restoreState(Bundle) was never called.

and this line:

Returns the same copy of the back/forward list used to save the state.

in the javadoc for WebView.saveState(Bundle).