为Webview片段加载微调器

Question

The following is the code in my ScoreFragment.java that shows a Webview.

IMPORT BLAH BLAH
public class ScoreFragment extends Fragment {

public ScoreFragment(){}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View mainView = inflater.inflate(R.layout.fragment_score, container, false);
    WebView myWebView = (WebView) mainView.findViewById(R.id.webview);
    myWebView.setWebViewClient(new WebViewClient(){
        public boolean shouldOverrideUrlLoading(WebView view, String url) 
        {
            return true;
        }
    });


    myWebView.loadUrl("xyz");
   return mainView;
}
}

This code is waht i used in my ACtivity for Another different project that also shows Webview , But this has a Loading spinner that shows up in the left of the action bar:

public class Facebook extends Activity {

WebView mWebView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.activity_facebook);



       mWebView = (WebView) findViewById( R.id.MyWebview ); 
       mWebView.setWebViewClient(new WebViewClient());
       mWebView.getSettings().setJavaScriptEnabled(true);   
       mWebView.getSettings().setSupportZoom(true);       
       mWebView.getSettings().setBuiltInZoomControls(false); 
       mWebView.loadUrl("https://www.facebook.com/thebanginbeats");

       final Activity MyActivity = this;
       mWebView.setWebViewClient(new WebViewClient() {

           @Override 
           public boolean shouldOverrideUrlLoading(WebView view, String url) {
              return false;
            }

           public void onBackPressed (){
               if (mWebView.canGoBack()) {
                    mWebView.goBack();       
                }
                else {
                    //My exit alert code goes here.    
                }
            }

           public void onReceivedSslError (WebView view, SslErrorHandler handler, SslError error)     {
               handler.proceed() ;
               }

           @Override
           public void onPageStarted(WebView view, String url, Bitmap favicon) {

            super.onPageStarted(view, url, favicon);
            setProgressBarIndeterminate(true);   
            setProgressBarIndeterminateVisibility(true);
           }


           @Override
           public void onPageFinished(WebView view, String url) {
               setProgressBarIndeterminate(false);   
                setProgressBarIndeterminateVisibility(false);
            super.onPageFinished(view, url);

           }


       } );

}


}

Adding the line of code "requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);" from the Activity into my Fragment doesn't work. What code would be required to be changed here>?

EDIT : I have changed the code in my fragment to this below. Also the menu.xml is under the menu directory and the item_layout.xml is under the layout directory. There are no errors except for the line " loading.setVisible(toggle); " which throws and error asking me to set it as Boolean toggle = false; Any idea as to what is causing it ?

And the line of code " getActivity().invalidateOptionsMenu()" should it be under onPageFinished ? *Show in code below

public class ScoreFragment extends Fragment {

public ScoreFragment(){}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View mainView = inflater.inflate(R.layout.fragment_score, container, false);
    WebView myWebView = (WebView) mainView.findViewById(R.id.webview);
    myWebView.setWebViewClient(new WebViewClient(){
        public boolean shouldOverrideUrlLoading(WebView view, String url) 
        {
            return true;
        }

        @Override
           public void onPageFinished(WebView view, String url) {
            getActivity().invalidateOptionsMenu(); //On finishing the page loading
            super.onPageFinished(view, url);

           }

    });


    myWebView.loadUrl("xyz");
   return mainView;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    setHasOptionsMenu(true); //This tells the parent activity that the Fragment wants  to add items to the Actionbar
}

@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
    inflater.inflate(R.menu.menu, menu);
    //Inflate the menu for this fragment
}

@Override
public void onPrepareOptionsMenu(Menu menu) {
    super.onPrepareOptionsMenu(menu);

    //This is the important part here you can switch the visibility of your menu item
    MenuItem loading = menu.findItem(R.id.progress_bar);

    //Here I use a boolean that is global to my class to set the visibility of the   item.
    loading.setVisible(toggle);
}



}

Answer 1

I'd suggest a custom view in you action bar, I mean, make your own progress bar.

Start creating an xml with the view for the progress bar, it can be just like this:

item_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<ProgressBar xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"/>

Then create the menu file:

menu.xml

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"> 
    <item
        android:id="@+id/progress_bar"
        app:showAsAction="always"
        android:title="Title"
        app:actionLayout="@layout/item_layout">
    </item>    
</menu>

As you can see we add the layout file we created as the action (or icon) for the menu item.

Now in your Fragment class you need to specify that you want to add something to the ActionBar . Just override the onActivityCreated method and use setHasOptionsMenu

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        setHasOptionsMenu(true); //This tells the parent activity that the Fragment wants to add items to the Actionbar
    }

Since you are using the Action Bar you need to override this two methods:

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        inflater.inflate(R.menu.menu, menu);
        //Inflate the menu for this fragment
    }

    @Override
    public void onPrepareOptionsMenu(Menu menu) {
        super.onPrepareOptionsMenu(menu);

        //This is the important part here you can switch the visibility of your menu item
        MenuItem loading = menu.findItem(R.id.progress_bar);
        //Here I use a boolean that is global to my class to set the visibility of the item.
        loading.setVisible(toggle);
    }

Finally whenever you want to change the visibility of the item all you need to do is call

getActivity().invalidateOptionsMenu();

This method will force the Action Bar to recreate and onPrepareOptionsMenu will be called. If you change the value of the boolean toggle you will toggle the visibility of the item as well.

Hope it helps!