In previous exercise "A simple example using Android's SQLite database", the result of queue was presented as string. It's going to be modified to exposes data from Cursor to a ListView widget.
Modify SQLiteAdapter.java to include a column of "_id" in our database, also include it in the queue. Modify the return of queueAll() to Cursor. Refer to the article "column '_id' does not exist".
package com.exercise.AndroidSQLite;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
public class SQLiteAdapter {
public static final String MYDATABASE_NAME = "MY_DATABASE";
public static final String MYDATABASE_TABLE = "MY_TABLE";
public static final int MYDATABASE_VERSION = 1;
public static final String KEY_ID = "_id";
public static final String KEY_CONTENT = "Content";
//create table MY_DATABASE (ID integer primary key, Content text not null);
private static final String SCRIPT_CREATE_DATABASE =
"create table " + MYDATABASE_TABLE + " ("
+ KEY_ID + " integer primary key autoincrement, "
+ KEY_CONTENT + " text not null);";
private SQLiteHelper sqLiteHelper;
private SQLiteDatabase sqLiteDatabase;
private Context context;
public SQLiteAdapter(Context c){
context = c;
}
public SQLiteAdapter openToRead() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getReadableDatabase();
return this;
}
public SQLiteAdapter openToWrite() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getWritableDatabase();
return this;
}
public void close(){
sqLiteHelper.close();
}
public long insert(String content){
ContentValues contentValues = new ContentValues();
contentValues.put(KEY_CONTENT, content);
return sqLiteDatabase.insert(MYDATABASE_TABLE, null, contentValues);
}
public int deleteAll(){
return sqLiteDatabase.delete(MYDATABASE_TABLE, null, null);
}
public Cursor queueAll(){
String[] columns = new String[]{KEY_ID, KEY_CONTENT};
Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns,
null, null, null, null, null);
return cursor;
}
public class SQLiteHelper extends SQLiteOpenHelper {
public SQLiteHelper(Context context, String name,
CursorFactory factory, int version) {
super(context, name, factory, version);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(SCRIPT_CREATE_DATABASE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
}
}
Create /res/layout/row.xml for our ListView
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/text"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="10dip"/>
Modify main.xml to change the result(contentlist) from TextView to ListView.
<?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:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello"
/>
<ListView
android:id="@+id/contentlist"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
</LinearLayout>
Finally, modify AndroidSQLite.java
package com.exercise.AndroidSQLite;
import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class AndroidSQLite extends Activity {
private SQLiteAdapter mySQLiteAdapter;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ListView listContent = (ListView)findViewById(R.id.contentlist);
/*
* Create/Open a SQLite database
* and fill with dummy content
* and close it
*/
mySQLiteAdapter = new SQLiteAdapter(this);
mySQLiteAdapter.openToWrite();
mySQLiteAdapter.deleteAll();
mySQLiteAdapter.insert("A for Apply");
mySQLiteAdapter.insert("B for Boy");
mySQLiteAdapter.insert("C for Cat");
mySQLiteAdapter.insert("D for Dog");
mySQLiteAdapter.insert("E for Egg");
mySQLiteAdapter.insert("F for Fish");
mySQLiteAdapter.insert("G for Girl");
mySQLiteAdapter.insert("H for Hand");
mySQLiteAdapter.insert("I for Ice-scream");
mySQLiteAdapter.insert("J for Jet");
mySQLiteAdapter.insert("K for Kite");
mySQLiteAdapter.insert("L for Lamp");
mySQLiteAdapter.insert("M for Man");
mySQLiteAdapter.insert("N for Nose");
mySQLiteAdapter.insert("O for Orange");
mySQLiteAdapter.insert("P for Pen");
mySQLiteAdapter.insert("Q for Queen");
mySQLiteAdapter.insert("R for Rain");
mySQLiteAdapter.insert("S for Sugar");
mySQLiteAdapter.insert("T for Tree");
mySQLiteAdapter.insert("U for Umbrella");
mySQLiteAdapter.insert("V for Van");
mySQLiteAdapter.insert("W for Water");
mySQLiteAdapter.insert("X for X'mas");
mySQLiteAdapter.insert("Y for Yellow");
mySQLiteAdapter.insert("Z for Zoo");
mySQLiteAdapter.close();
/*
* Open the same SQLite database
* and read all it's content.
*/
mySQLiteAdapter = new SQLiteAdapter(this);
mySQLiteAdapter.openToRead();
Cursor cursor = mySQLiteAdapter.queueAll();
startManagingCursor(cursor);
String[] from = new String[]{SQLiteAdapter.KEY_CONTENT};
int[] to = new int[]{R.id.text};
SimpleCursorAdapter cursorAdapter =
new SimpleCursorAdapter(this, R.layout.row, cursor, from, to);
listContent.setAdapter(cursorAdapter);
mySQLiteAdapter.close();
}
}
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