Android记事本程序源码

1、MainActivity

package cn.dccssq;

import android.app.ListActivity;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

public class MainActivity extends ListActivity {

private static final int INSERT_ID = Menu.FIRST;

private static final int DELETE_ID = Menu.FIRST + 1;

private static final int ACTIVITY_CREATE = 0;

private static final int ACTIVITY_EDIT = 1;

private DiaryDbAdapter diaryDb;

private Cursor cursor;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

diaryDb =new DiaryDbAdapter(this);
diaryDb.open();

}

private void showListView(){
cursor = diaryDb.getAllNotes();

String[] from = new String[]{DiaryDbAdapter.KEY_TITLE,DiaryDbAdapter.KEY_BODY};
int[] to = new int[]{R.id.text1,R.id.created};

ListAdapter cursorAdapter = new SimpleCursorAdapter(this,R.layout.diary_row,cursor,from,to);
setListAdapter(cursorAdapter);
}

@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
// TODO Auto-generated method stub
super.onListItemClick(l, v, position, id);
Cursor c = cursor;
c.move(position);
Intent intent = new Intent(this,ActivityDiary.class);
intent.putExtra(DiaryDbAdapter.KEY_ROWID, id);
intent.putExtra(DiaryDbAdapter.KEY_TITLE, c.getString(c
.getColumnIndexOrThrow(DiaryDbAdapter.KEY_TITLE)));
intent.putExtra(DiaryDbAdapter.KEY_BODY, c.getString(c
.getColumnIndexOrThrow(DiaryDbAdapter.KEY_BODY)));
startActivityForResult(intent, ACTIVITY_EDIT);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
showListView();
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// TODO Auto-generated method stub
super.onCreateOptionsMenu(menu);
menu.add(0,INSERT_ID,0,R.string.menu_insert);
menu.add(0,DELETE_ID,0,R.string.menu_delete);
return true;
}

@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
// TODO Auto-generated method stub
switch(item.getItemId()){
case INSERT_ID:
Log.i("INSERT:", String.valueOf(INSERT_ID));
createDiary();
return true;
case DELETE_ID:
Log.i("DELETE_ID:", String.valueOf(getListView().getSelectedItemId()));
diaryDb.deleteDiary(getListView().getSelectedItemId());
showListView();
return true;
}
return super.onMenuItemSelected(featureId, item);
}

private void createDiary(){

Intent intent = new Intent();
intent.setClass(this, ActivityDiary.class);
startActivityForResult(intent, ACTIVITY_CREATE);
}
}

2、ActivityDiary

package cn.dccssq;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class ActivityDiary extends Activity {

// title EditText
EditText titleTxt;
// body EditText
EditText bodyTxt;
// save Button
Button btn;
// Row Id
Long rowId;
private DiaryDbAdapter diaryDb;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.notepad);

// Initialize the DiaryDbAdapter.
diaryDb = new DiaryDbAdapter(this);

// Get the screen control
titleTxt = (EditText)findViewById(R.id.title);
bodyTxt = (EditText)findViewById(R.id.body_text);
btn = (Button)findViewById(R.id.button);
rowId = null ;

// Get data from the front page
Bundle bundle = getIntent().getExtras();

if(bundle!=null){
Log.i("bund:",bundle.toString());

// Set data to page
String title = bundle.getString(DiaryDbAdapter.KEY_TITLE);
String body = bundle.getString(DiaryDbAdapter.KEY_BODY);
rowId = bundle.getLong(DiaryDbAdapter.KEY_ROWID);
if(title!=null)
{
titleTxt.setText(title);
}
if(body!=null)
{
bodyTxt.setText(body);
}
}

btn.setOnClickListener(new View.OnClickListener() {

public void onClick(View arg0) {
// TODO Auto-generated method stub
String title = titleTxt.getText().toString();
String body = bodyTxt.getText().toString();
if(checkInput(title, body)){
diaryDb.open();
if(rowId!=null){
diaryDb.updateDiary(rowId, title, body);
}else{
diaryDb.createDiary(title, body);
}
diaryDb.close();

Intent mIntent = new Intent();
setResult(RESULT_OK, mIntent);

finish();
}
}
});
}

/**
* Validate the input.
* @param title
* @param body
* @return
*/
public boolean checkInput(String title ,String body){

if(null==title || title.trim().length()==0){
titleTxt.setError("Please input the title!");
return false;
}

if(null==body || body.trim().length()==0){
bodyTxt.setError("Please input the content!");
return false;
}
return true;
}
}

3、DiaryDbAdapter DB操作类，提供了两种增删查改的功能代码

package cn.dccssq;

import java.util.Calendar;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;

public class DiaryDbAdapter {
public static final String KEY_TITLE = "title";
public static final String KEY_BODY = "body";
public static final String KEY_ROWID = "_id";
public static final String KEY_CREATED = "created";

private DatabaseHelper databaseHelper;

private Context context;

private SQLiteDatabase sqliteDatabase;

public DiaryDbAdapter(Context context) {
this.context = context;
}

/**
* Open the Database
*/
public void open(){
databaseHelper = new DatabaseHelper(context);

try
{
sqliteDatabase = databaseHelper.getWritableDatabase();
}catch(SQLiteException e){
sqliteDatabase = databaseHelper.getReadableDatabase();
}
}

/**
* Close the Database
*/
public void close()
{
sqliteDatabase.close();
}

/**
* Insert the Data
* @param title
* @param body
* @return
*/
public long createDiary(String title,String body){

ContentValues content = new ContentValues();
content.put(KEY_TITLE, title);
content.put(KEY_BODY, body);
Calendar calendar = Calendar.getInstance();
String created = calendar.get(Calendar.YEAR) + "/"
+ calendar.get(Calendar.MONTH) + "/"
+ calendar.get(Calendar.DAY_OF_MONTH) + " "
+ calendar.get(Calendar.HOUR_OF_DAY) + ":"
+ calendar.get(Calendar.MINUTE);
content.put(KEY_CREATED, created);

return sqliteDatabase.insert(databaseHelper.DATABSE_TABLE, null, content);
}

/**
* Delete the record
* @param rowId
* @return
*/
public boolean deleteDiary(long rowId){

String whereString = KEY_ROWID + "=" + rowId;
return sqliteDatabase.delete(databaseHelper.DATABSE_TABLE, whereString, null)>0;
}

/**
* Get all Records
* @return
*/
public Cursor getAllNotes()
{
String[] searchResult =  {KEY_ROWID, KEY_TITLE,KEY_BODY, KEY_CREATED};
return sqliteDatabase.query(databaseHelper.DATABSE_TABLE, searchResult, null, null, null, null, null);
}

/**
* Get the record by condition
* @param rowId
* @return
* @throws SQLException
*/
public Cursor getDiary(long rowId) throws SQLException{

String[] searchResult =  {KEY_ROWID, KEY_TITLE,KEY_BODY, KEY_CREATED};
String whereString = KEY_ROWID + "=" + rowId;

Cursor mCursor = sqliteDatabase.query(true, databaseHelper.DATABSE_TABLE, searchResult, whereString, null, null, null, null, null);
if(mCursor!=null){
mCursor.moveToFirst();
}
return mCursor;
}

public boolean updateDiary(long rowId ,String title,String body){

ContentValues values = new ContentValues();
values.put(KEY_ROWID, title);
values.put(KEY_BODY,body);

Calendar calendar = Calendar.getInstance();
String created = calendar.get(Calendar.YEAR) + "/"
+ calendar.get(Calendar.MONTH) + "/"
+ calendar.get(Calendar.DAY_OF_MONTH) + " "
+ calendar.get(Calendar.HOUR_OF_DAY) + ":"
+ calendar.get(Calendar.MINUTE);
values.put(KEY_CREATED, created);
String whereString = KEY_ROWID + "=" + rowId;

return sqliteDatabase.update(databaseHelper.DATABSE_TABLE, values, whereString, null)>0;
}

public void xinjianDiary(String title,String body){

Calendar calendar = Calendar.getInstance();
String created = calendar.get(Calendar.YEAR) + "/"
+ calendar.get(Calendar.MONTH) + "/"
+ calendar.get(Calendar.DAY_OF_MONTH) + " "
+ calendar.get(Calendar.HOUR_OF_DAY) + ":"
+ calendar.get(Calendar.MINUTE);

String insertSQL = "INSERT INTO " + databaseHelper.DATABSE_TABLE
+"(" + KEY_ROWID +"," + KEY_TITLE+"," + KEY_BODY +"," + KEY_CREATED + ")"
+ " values (?,?,?,?)" ;
Object[] args = {null,title,body,created};
sqliteDatabase.execSQL(insertSQL, args);
}

public void bianjiDiary(long rowId ,String title,String body){
Calendar calendar = Calendar.getInstance();
String created = calendar.get(Calendar.YEAR) + "/"
+ calendar.get(Calendar.MONTH) + "/"
+ calendar.get(Calendar.DAY_OF_MONTH) + " "
+ calendar.get(Calendar.HOUR_OF_DAY) + ":"
+ calendar.get(Calendar.MINUTE);

String updateSQL = "update " + databaseHelper.DATABSE_TABLE
+" set " + KEY_TITLE+"=? ," + KEY_BODY +"=? ," + KEY_CREATED + "=? "
+ " where " + KEY_ROWID + "= ?" ;
Object[] args = {title,body,created,rowId};
sqliteDatabase.execSQL(updateSQL, args);
}

public void shanchuDiary(long rowId ){
String deleteSQL = "delete from "+ databaseHelper.DATABSE_TABLE +" where " + KEY_ROWID + "= ?" ;
Object[] args = {rowId};
sqliteDatabase.execSQL(deleteSQL, args);
}

public Cursor qudeAllNotes()
{
String searchSQL = "select _id , title , body ,created from "+ databaseHelper.DATABSE_TABLE;
return sqliteDatabase.rawQuery(searchSQL, null);
}
}

4、DatabaseHelper

package cn.dccssq;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHelper extends SQLiteOpenHelper {

private final static String DATABSE_NAME = "notepad";
private final static int DATABASE_VERSION = 1;
public final static String DATABSE_TABLE = "diary";

private final static String DATABASE_CREATE = "create table " + DATABSE_TABLE + " (_id integer primary key autoincrement,"
+ "title text not null, body text not null, created text not null);";
public DatabaseHelper(Context context) {
super(context, DATABSE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(DATABASE_CREATE);
}

@Override
public void onUpgrade(SQLiteDatabase db, int arg1, int arg2) {
db.execSQL("DROP TABLE IF EXISTS " + DATABSE_TABLE);
onCreate(db);
}

}

5、main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ListView
android:id="@+id/android:list"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/android:empty"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="您还没有开始写日记呢!点击下边的Menu按钮开始写日记吧:)" />
</LinearLayout>

6、diary_row.xml

<?xml version="1.0" encoding="utf-8" ?>
<RelativeLayout
android:id="@+id/row"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:id="@+id/text1"
android:layout_width="wrap_content"
android:layout_height="30px"
android:maxWidth="200dip"
android:textSize="22sp"
android:layout_marginTop="10dip"
android:text="第一组第一项" />
<TextView
android:id="@+id/created"
android:layout_width="wrap_content"
android:layout_height="35px"
android:layout_alignParentRight="true"
android:layout_marginLeft="10dip"
android:layout_marginTop="10dip"
android:text="1999年12月3号" />
</RelativeLayout>

7、notepadxml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:text="@string/notepad_title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></TextView>
<EditText
android:id="@+id/title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></EditText>
<TextView
android:text="@string/notepad_body"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></TextView>
<EditText
android:id="@+id/body_text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></EditText>
<Button
android:id="@+id/button"
android:text="@string/notepad_button"
android:layout_width="fill_parent"
android:layout_height="wrap_content"></Button>
</LinearLayout>

8、strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Hello World, MainActivity!</string>
<string name="app_name">db2</string>

<string name="diary_edit">编辑</string>
<string name="notepad_title">标题:</string>
<string name="notepad_body">内容:</string>
<string name="notepad_button">确定:</string>
<string name="menu_insert">Add</string>
<string name="menu_delete">Delete</string>
<string name="edit_diary">Edit</string>
</resources>

9、AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="cn.dccssq"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name=".MainActivity"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ActivityDiary">
</activity>
</application>
<uses-sdk android:minSdkVersion="8" />

</manifest>