• 0

addJavascriptInterface on Createview element?


Question

MainActivity.class 

package com.example.app;

import android.app.Activity;
import android.app.ActionBar;
import android.app.Fragment;
import android.app.FragmentManager;
import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.support.v4.widget.DrawerLayout;
import android.webkit.WebView;
import android.webkit.WebSettings;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import android.webkit.WebViewClient;
import android.webkit.JavascriptInterface;

public class MainActivity extends Activity
        implements NavigationDrawerFragment.NavigationDrawerCallbacks {

    /**
     * Fragment managing the behaviors, interactions and presentation of the navigation drawer.
     */
    private NavigationDrawerFragment mNavigationDrawerFragment;

    /**
     * Used to store the last screen title. For use in {@link #restoreActionBar()}.
     */
    private CharSequence mTitle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mNavigationDrawerFragment = (NavigationDrawerFragment)
                getFragmentManager().findFragmentById(R.id.navigation_drawer);
        mTitle = getTitle();

        // Set up the drawer.
        mNavigationDrawerFragment.setUp(
                R.id.navigation_drawer,
                (DrawerLayout) findViewById(R.id.drawer_layout));

        final WebAppInterface myjsinterface = new WebAppInterface(this);
    }

    @Override
    public void onNavigationDrawerItemSelected(int position) {
        // update the main content by replacing fragments
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.container, PlaceholderFragment.newInstance(position + 1))
                .commit();
    }

    public void onSectionAttached(int number) {
        switch (number) {
            case 1:
                mTitle = getString(R.string.title_section0);
                break;
            case 2:
                mTitle = getString(R.string.title_section1);
                break;
            case 3:
                mTitle = getString(R.string.title_section2);
                break;
            case 4:
                mTitle = getString(R.string.title_section3);
                break;
        }
    }

    public void restoreActionBar() {
        ActionBar actionBar = getActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
        actionBar.setDisplayShowTitleEnabled(true);
        actionBar.setTitle(mTitle);
        //actionBar.hide();
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        if (!mNavigationDrawerFragment.isDrawerOpen()) {
            // Only show items in the action bar relevant to this screen
            // if the drawer is not showing. Otherwise, let the drawer
            // decide what to show in the action bar.
            getMenuInflater().inflate(R.menu.main, menu);
            restoreActionBar();
            return true;
        }
        return super.onCreateOptionsMenu(menu);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main, container, false);
            //TextView textView = (TextView) rootView.findViewById(R.id.section_label);
            //textView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
            WebView content = (WebView) rootView.findViewById(R.id.webview);
            content.setBackgroundColor(0x00000000);
            content.getSettings().setJavaScriptEnabled(true);
            content.addJavascriptInterface(new WebAppInterface(this), "Android"); //Gives error: android.content.Context cannot be applied to com.example.app.MainActivity.PlaceHolderfragment :/
            if(getArguments().getInt(ARG_SECTION_NUMBER) == 1) {
                content.loadUrl("http://www.checkbestsellers.com/app/v1/");
            }
            return rootView;
        }

        @Override
        public void onAttach(Activity activity) {
            super.onAttach(activity);
            ((MainActivity) activity).onSectionAttached(
                    getArguments().getInt(ARG_SECTION_NUMBER));
        }

    }

}

WebAppInterface.class:

package com.example.app;

import android.app.ActionBar;
import android.content.Context;
import android.webkit.JavascriptInterface;
import android.widget.Toast;
import android.app.Activity;


public class WebAppInterface extends Activity {
    Context mContext;

    /** Instantiate the interface and set the context */
    WebAppInterface(Context c) {
        mContext = c;
    }

    /** Show a toast from the web page */
    @JavascriptInterface
    public void showToast(String toast) {
        Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
    }
    @JavascriptInterface
    public void toggleActionbar(int toggle) {
        ActionBar ActionBar = getActionBar();
        if(toggle == 0){
            ActionBar.hide();
        } else {
            ActionBar.show();
        }
    }
}

What am I doing wrong? See line at MainActivity.class: content.addJavascriptInterface(new WebAppInterface(this), "Android"); //Gives error: android.content.Context cannot be applied to com.example.app.MainActivity.PlaceHolderfragment :/

 

This problem only occurs when using a dynamic fragment layout, when I just put a webview in the mainactivity and apply the code to that it works :/

 

And It uses the Navigationdrawer fragment layout from androidstudio.

 

Thanks for any help, I'm new to android stuff ^^

 

*Ignore some unneccessary imports, I'll look into that when I get this working first

3 answers to this question

Recommended Posts

  • 0
  On 09/03/2014 at 10:35, Majesticmerc said:

wisdom_of_the_ancients.png

:p

Hahahahhahaa

I changed:

content.addJavascriptInterface(new WebAppInterface(this), "Android");

to:

content.addJavascriptInterface(new WebAppInterface(getActivity()), "Android");
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