Android example source code file (HistoryActivity.java)

This example Android source code file (HistoryActivity.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, column_names, from, history, input, listactivity, map, menuinflater, onitemclicklistener, os, output, override, simpleadapter, string, to, ui, util, view, view_ids, widget

The HistoryActivity.java Android example source code

/*
 * Copyright (C) 2008 Google Inc.
 *
 * 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 com.beust.android.translate;

import android.app.ListActivity;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.SimpleAdapter;
import android.widget.AdapterView.OnItemClickListener;

import java.util.List;
import java.util.Map;

/**
 * This activity displays the history of past translations.
 *
 * @author Cedric Beust
 * @author Daniel Rall
 */
public class HistoryActivity extends ListActivity implements OnItemClickListener {
    private SimpleAdapter mAdapter;
    private List<Map mListData;
    private History mHistory;

    private static final String INPUT = "input";
    private static final String OUTPUT = "output";
    private static final String FROM = "from";
    private static final String TO = "to";
    private static final String FROM_SHORT_NAME = "from-short-name";
    private static final String TO_SHORT_NAME = "to-short-name";

    // These constants are used to bind the adapter to the list view
    private static final String[] COLUMN_NAMES = { INPUT, OUTPUT, FROM, TO };
    private static final int[] VIEW_IDS = { R.id.input, R.id.output, R.id.from, R.id.to };

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.history_activity);
        
        mHistory = new History(TranslateActivity.getPrefs(this));
        initializeAdapter(mHistory.getHistoryRecordsMostRecentFirst());
        getListView().setEmptyView(findViewById(R.id.empty));
    }
    
    private void initializeAdapter(List<HistoryRecord> historyRecords) {
        mListData = Lists.newArrayList();
        
        for (HistoryRecord hr : historyRecords) {
            Map<String, String> data = Maps.newHashMap();

            // Values that are bound to views
            data.put(INPUT, hr.input);
            data.put(OUTPUT, hr.output);
            data.put(FROM, hr.from.name().toLowerCase());
            data.put(TO, hr.to.name().toLowerCase());

            // Extra values we keep around for convenience
            data.put(FROM_SHORT_NAME, hr.from.getShortName());
            data.put(TO_SHORT_NAME, hr.to.getShortName());
            mListData.add(data);
        }
        
        mAdapter = new SimpleAdapter(this, mListData, R.layout.history_record,
                COLUMN_NAMES, VIEW_IDS);
        getListView().setAdapter(mAdapter);
        getListView().setOnItemClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.history_activity_menu, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch(item.getItemId()) {
        case R.id.most_recent:
            initializeAdapter(mHistory.getHistoryRecordsMostRecentFirst());
            break;

        case R.id.languages:
            initializeAdapter(mHistory.getHistoryRecordsByLanguages());
            break;

        case R.id.clear_history:
            mHistory.clear(this);
            initializeAdapter(mHistory.getHistoryRecordsByLanguages());
            break;
        }
        
        return true;
    }

    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        Map<String, String> data = (Map) parent.getItemAtPosition(position);
        Editor edit = TranslateActivity.getPrefs(this).edit();
        TranslateActivity.savePreferences(edit,
                data.get(FROM_SHORT_NAME), data.get(TO_SHORT_NAME), 
                data.get(INPUT), data.get(OUTPUT));
        finish();
    }
}