Show/Hide WebViews in Android

Question

I have multiple WebViews stored in a HashMap which I need to be able to show/hide at any time.

When a row in a ListView is tapped, I need to show the WebView associated with that row and hide all the others. The other WebViews cannot be destroyed as I do not wish to unload their contents.

Is this possible?

Creation and storage of the WebView in one Fragment :

public WebView createWebView(Long id) {
    WebView wv = new WebView(getActivity());
    wv.setWebViewClient(new WebViewClient() {
        @Override
        public void onPageFinished(WebView view, String url) {
            view.loadUrl("javascript:(registerCredentialsChangedCallback(function(credentials) {if (credentials.length >= 1) {window.location.href = 'callback:' + credentials;} else {alert('Error: callback set by registerCredentialsChangedCallback was given null string');}})) ()");
        }
    });
    WebSettings webSettings = wv.getSettings();
    webSettings.setJavaScriptEnabled(true);
    webSettings.setUseWideViewPort(true);
    webSettings.setLoadWithOverviewMode(true);

    wv.loadUrl(makeViewerURL(id));

    webViews.put(id, wv);

    return wv;
}

onCreate in another Fragment . I'm using an interface to pass the id via the Activity to the Fragment where the WebView should be displayed:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_directory, container, false);

    ListView listView = (ListView) rootView.findViewById(R.id.list);

    DatabaseHelper dbHelper = new DatabaseHelper(getActivity());
    android.R.layout.simple_list_item_1, android.R.id.text1, values);

    final SimpleCursorAdapter adapter = new SimpleCursorAdapter(getActivity(), android.R.layout.simple_list_item_1, dbHelper.getViewers(), new String[] { "description", "_id" }, new int[] { android.R.id.text1 }, CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
    listView.setAdapter(adapter);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            Long id = adapter.getItemId(i);

            mCallback.onViewerSelected(id);
        }
    });

    return rootView;
}

XML Layout of View which should contain WebView:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="#FFFFFF" >

    <WebView  xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/webview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />
</RelativeLayout>

Thanks!

Answer 1

Yes, it is possible - but you need to have a key value pairs of id and WebView .

private Map<Long, View> mWebViews = new HashMap<Long, View>();

listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            Long id = adapter.getItemId(i);
            if(mViews.contains(id))
               mWebView = mViews.get(id)
            else
               mWebView = createWebView();
        }
    });

Then you just need to find the corresponding WebView which the user selected in List and make it visible. In order to hide the WebView you need to use:

mWebView.setVisibility(View.Gone);

Addenda: instead of webView in your xml file, use a frameLayout such as:

<FrameLayout
            android:id="@+id/web_container"
            android:layout_width="fill_parent"
            android:layout_height="420dip"
            android:layout_gravity="center"
            android:clickable="true"
            android:enabled="true"
            android:paddingLeft="10dip"
            android:paddingRight="10dip" />

And then in the code add the WebView to Framelayout:

FrameLayout mWebContainer = (FrameLayout) findViewById(R.id.web_container);
webView = new WebView(getApplicationContext());
mWebContainer.addView(webView);