snow10-android/java/net/chaoswebs/snow10/MainActivity.java

package net.chaoswebs.snow10;

import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.webkit.WebView;
import android.webkit.WebViewClient;

public class MainActivity extends AppCompatActivity {
    /*  Snow10 - Whitespace steganography. electronic invisible ink.
    Copyright (C) 2017  Kevin Froman https://ChaosWebs.net/
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
    */

    private WebView view;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        view = new WebView(this);
        view.setWebViewClient(new WebViewClient(){
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                if (url != null && url.startsWith("http://") || url.startsWith("https://")) {
                    view.getContext().startActivity(
                            new Intent(Intent.ACTION_VIEW, Uri.parse(url)));
                    return true;
                } else {
                    return false;
                }
            }

        });

        view.getSettings().setJavaScriptEnabled(true);
        view.loadUrl("file:///android_asset/index.html");
        setContentView(view);



    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if ((keyCode == KeyEvent.KEYCODE_BACK) && view.canGoBack()) {
            //if Back key pressed and webview can navigate to previous page
            view.goBack();
            // go back to previous page
            return true;
        }
        else
        {
            finish();
            // finish the activity
        }
        return super.onKeyDown(keyCode, event);
    }

}