fr.umlv.lastproject.smart.browser.FileChooserActivity.java Source code

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Here is the source code for fr.umlv.lastproject.smart.browser.FileChooserActivity.java

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/* 
 * Copyright (C) 2012 Paul Burke
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at 
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0 
 * 
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 * See the License for the specific language governing permissions and 
 * limitations under the License. 
 */

package fr.umlv.lastproject.smart.browser;

import java.io.File;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentManager.BackStackEntry;
import android.support.v4.app.FragmentManager.OnBackStackChangedListener;
import android.support.v4.app.FragmentTransaction;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;
import fr.umlv.lastproject.smart.Preferences;
import fr.umlv.lastproject.smart.PreferencesException;
import fr.umlv.lastproject.smart.R;

/**
 * Main Activity that handles the FileListFragments
 * 
 * @version 2012-10-28
 * 
 * @author paulburke (ipaulpro), marc barat
 * 
 */
public class FileChooserActivity extends FragmentActivity implements OnBackStackChangedListener {

    private FragmentManager mFragmentManager;
    private String mPath;
    private Preferences pref;
    private BroadcastReceiver mStorageListener = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            Toast.makeText(context, R.string.storage_removed, Toast.LENGTH_LONG).show();
            finishWithResult(null);
        }
    };
    public static final String PATH = "path";
    public static final String EXTERNAL_BASE_PATH = Environment.getExternalStorageDirectory().getAbsolutePath();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        try {
            pref = Preferences.create(this);
        } catch (PreferencesException e) {
            Toast.makeText(this, getString(R.string.unableLoadPref), Toast.LENGTH_LONG).show();
        }
        setTheme(pref.getTheme());
        setContentView(R.layout.chooser);

        mFragmentManager = getSupportFragmentManager();
        mFragmentManager.addOnBackStackChangedListener(this);

        if (savedInstanceState == null) {
            Bundle bundle = getIntent().getExtras();
            mPath = (String) bundle.get(PATH);
            addFragment();
        } else {
            mPath = savedInstanceState.getString(PATH);
        }

        setTitle(mPath);
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterStorageListener();
        try {
            pref.save();
        } catch (PreferencesException e) {
            Toast.makeText(this, getString(R.string.unableLoadPref), Toast.LENGTH_LONG).show();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        registerStorageListener();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);

        outState.putString(PATH, mPath);
    }

    @Override
    public void onBackStackChanged() {
        mPath = EXTERNAL_BASE_PATH;

        int count = mFragmentManager.getBackStackEntryCount();
        if (count > 0) {
            BackStackEntry fragment = mFragmentManager.getBackStackEntryAt(count - 1);
            mPath = fragment.getName();
        }

        setTitle(mPath);
    }

    /**
     * Add the initial Fragment with given path.
     * 
     * @param path
     *            The absolute path of the file (directory) to display.
     */
    private void addFragment() {
        FileListFragment explorerFragment = FileListFragment.newInstance(mPath);
        mFragmentManager.beginTransaction().add(R.id.explorer_fragment, explorerFragment).commit();
    }

    /**
     * "Replace" the existing Fragment with a new one using given path. We're
     * really adding a Fragment to the back stack.
     * 
     * @param path
     *            The absolute path of the file (directory) to display.
     */
    private void replaceFragment(String path) {
        FileListFragment explorerFragment = FileListFragment.newInstance(path);
        mFragmentManager.beginTransaction().replace(R.id.explorer_fragment, explorerFragment)
                .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN).addToBackStack(path).commit();
    }

    /**
     * Finish this Activity with a result code and URI of the selected file.
     * 
     * @param file
     *            The file selected.
     */
    private void finishWithResult(File file) {
        if (file != null) {
            Uri uri = Uri.fromFile(file);
            setResult(RESULT_OK, new Intent().setData(uri));
            finish();
        } else {
            setResult(RESULT_CANCELED);
            finish();
        }
    }

    /**
     * Called when the user selects a File
     * 
     * @param file
     *            The file that was selected
     */
    protected void onFileSelected(File file) {
        if (file != null) {
            mPath = file.getAbsolutePath();

            if (file.isDirectory()) {
                replaceFragment(mPath);
            } else {
                finishWithResult(file);
            }
        } else {
            Toast.makeText(FileChooserActivity.this, R.string.error_selecting_file, Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Register the external storage BroadcastReceiver.
     */
    private void registerStorageListener() {
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_MEDIA_REMOVED);
        registerReceiver(mStorageListener, filter);
    }

    /**
     * Unregister the external storage BroadcastReceiver.
     */
    private void unregisterStorageListener() {
        unregisterReceiver(mStorageListener);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_smart, menu);
        menu.add(0, 1, 0, R.string.directory);

        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        finishWithResult(new File(mPath));
        return true;
    }
}