com.littlepancake.glpk.HelpFragment.java Source code

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Here is the source code for com.littlepancake.glpk.HelpFragment.java

Source

/*
   Copyright 2014, Joseph Rios, Littlepancake Software, info@littlepancake.com
    
   This file is part of the GLPK on Android.
    
GLPK on Android 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.
    
GLPK on Android 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 GLPK on Android.  If not, see <http://www.gnu.org/licenses/>.
    
 */

package com.littlepancake.glpk;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.Intent;
import android.content.res.AssetManager;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;

@SuppressLint("WorldReadableFiles")
@SuppressWarnings("deprecation")
public class HelpFragment extends Fragment implements OnClickListener {

    private final String glpkPdfName = "glpk.pdf";
    private final String gplv3FileName = "gplv3.txt";
    private Button manualButton, gplButton;
    private final int buff_size = 1024;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.help_layout, container, false);
        manualButton = (Button) v.findViewById(R.id.readButton);
        manualButton.setOnClickListener(this);
        gplButton = (Button) v.findViewById(R.id.readGplv3);
        gplButton.setOnClickListener(this);
        return v;
    }

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

    /* Taken from here:
     * http://stackoverflow.com/questions/17085574/read-a-pdf-file-from-assets-folder
     * with a few small changes.
     */
    private void openGlpkPdf() {
        AssetManager assetManager = getActivity().getAssets();

        File file = new File(getActivity().getFilesDir(), glpkPdfName);

        if (!file.exists()) {
            InputStream in = null;
            OutputStream out = null;
            try {
                in = assetManager.open(glpkPdfName);
                /* Note that "MODE_WORLD_READABLE" is "dangerous". It seems the alternative is
                 * for me to write a few hundred more lines of code or something. Guess I'll
                 * remain dangerous for this app.
                 * See:
                 *  https://github.com/commonsguy/cw-omnibus/tree/master/ContentProvider/Files
                 * for the proper, code-intensive way to handle this.
                 */
                out = getActivity().openFileOutput(file.getName(), Context.MODE_WORLD_READABLE);
                byte[] buffer = new byte[buff_size];
                int read;
                while ((read = in.read(buffer)) != -1) {
                    out.write(buffer, 0, read);
                }
                in.close();
                out.flush();
                out.close();
                out = null;
                in = null;
            } catch (IOException e) {
                Log.e("tag", e.getMessage());
            }
        } else {
            //Log.d("tag", glpkPdfName+" already exists.");
        }

        Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setDataAndType(Uri.parse("file://" + getActivity().getFilesDir() + "/" + glpkPdfName),
                "application/pdf");
        startActivity(intent);
    }

    private void openGplTxt() {
        AssetManager assetManager = getActivity().getAssets();

        File file = new File(getActivity().getFilesDir(), gplv3FileName);

        if (!file.exists()) {
            InputStream in = null;
            OutputStream out = null;
            try {
                in = assetManager.open(gplv3FileName);
                /* Note that "MODE_WORLD_READABLE" is "dangerous". It seems the alternative is
                 * for me to write a few hundred more lines of code or something. Guess I'll
                 * remain dangerous for this app.
                 * See:
                 *  https://github.com/commonsguy/cw-omnibus/tree/master/ContentProvider/Files
                 * for the proper, code-intensive way to handle this.
                 */
                out = getActivity().openFileOutput(file.getName(), Context.MODE_WORLD_READABLE);
                byte[] buffer = new byte[buff_size];
                int read;
                while ((read = in.read(buffer)) != -1) {
                    out.write(buffer, 0, read);
                    Log.d("tag", "Read and wrote " + read + " bytes.");
                }
                in.close();
                out.flush();
                out.close();
            } catch (IOException e) {
                Log.e("tag", e.getMessage());
            }
        } else {
            //Log.d("tag", gplv3FileName+" already exists.");
        }

        Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setDataAndType(Uri.parse("file://" + getActivity().getFilesDir() + "/" + gplv3FileName),
                "text/plain");
        startActivity(intent);
    }

    @Override
    public void onClick(View v) {
        int id = v.getId();
        if (id == manualButton.getId()) {
            openGlpkPdf();
        } else if (id == gplButton.getId()) {
            openGplTxt();
        }
    }
}