android SQLite数据库基本操作示例

import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Color;
import android.os.Bundle;
import android.view.KeyEvent;
import android.widget.LinearLayout;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

public class Activity01 extends Activity {
	private static int miCount = 0;

	/* 数据库对象 */
	private SQLiteDatabase mSQLiteDatabase = null;

	private final static String DATABASE_NAME = "SQLite.db";

	/* 表名 */
	private final static String TABLE_NAME = "table1";

	/* 表中的字段 */
	private final static String TABLE_ID = "_id";

	private final static String TABLE_NUM = "num";

	private final static String TABLE_DATA = "data";

	/* 创建表的sql语句 */
	private final static String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME
			+ " (" + TABLE_ID + " INTEGER PRIMARY KEY," + TABLE_NUM
			+ " INTERGER," + TABLE_DATA + " TEXT)";

	/* 线性布局 */
	LinearLayout m_LinearLayout = null;

	/* 列表视图-显示数据库中的数据 */
	ListView m_ListView = null;

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

		/* 创建LinearLayout布局对象 */
		m_LinearLayout = new LinearLayout(this);
		/* 设置布局LinearLayout的属性 */
		m_LinearLayout.setOrientation(LinearLayout.VERTICAL);
		m_LinearLayout.setBackgroundColor(android.graphics.Color.BLACK);

		/* 创建ListView对象 */
		m_ListView = new ListView(this);
		LinearLayout.LayoutParams param = new LinearLayout.LayoutParams(
				LinearLayout.LayoutParams.FILL_PARENT,
				LinearLayout.LayoutParams.WRAP_CONTENT);
		m_ListView.setBackgroundColor(Color.BLACK);

		/* 添加m_ListView到m_LinearLayout布局 */
		m_LinearLayout.addView(m_ListView, param);

		/* 设置显示m_LinearLayout布局 */
		setContentView(m_LinearLayout);

		// 打开已经存在的数据库
		mSQLiteDatabase = this.openOrCreateDatabase(DATABASE_NAME,
				MODE_PRIVATE, null);

		// 获取数据库Phones的Cursor
		try {
			/* 在数据库mSQLiteDatabase中创建一个表 */
			mSQLiteDatabase.execSQL(CREATE_TABLE);
		} catch (Exception e) {
			UpdataAdapter();
		}
	}

	public boolean onKeyUp(int keyCode, KeyEvent event) {
		switch (keyCode) {
		case KeyEvent.KEYCODE_DPAD_LEFT:
			AddData();
			break;
		case KeyEvent.KEYCODE_DPAD_RIGHT:
			DeleteData();
			break;
		case KeyEvent.KEYCODE_1:
			UpData();
			break;
		case KeyEvent.KEYCODE_2:
			DeleteTable();
			break;
		case KeyEvent.KEYCODE_3:
			DeleteDataBase();
			break;
		}
		return true;
	}

	/* 删除数据库 */
	public void DeleteDataBase() {
		this.deleteDatabase(DATABASE_NAME);
		this.finish();
	}

	/* 删除一个表 */
	public void DeleteTable() {
		mSQLiteDatabase.execSQL("DROP TABLE " + TABLE_NAME);
		this.finish();
	}

	/* 更新一条数据 */
	public void UpData() {
		ContentValues cv = new ContentValues();
		cv.put(TABLE_NUM, miCount);
		cv.put(TABLE_DATA, "修改后的数据" + miCount);

		/* 更新数据 */
		mSQLiteDatabase.update(TABLE_NAME, cv,
				TABLE_NUM + "=" + Integer.toString(miCount - 1), null);

		UpdataAdapter();
	}

	/* 向表中添加一条数据 */
	public void AddData() {
		ContentValues cv = new ContentValues();
		cv.put(TABLE_NUM, miCount);
		cv.put(TABLE_DATA, "测试数据库数据" + miCount);
		/* 插入数据 */
		mSQLiteDatabase.insert(TABLE_NAME, null, cv);
		miCount++;
		UpdataAdapter();
	}

	/* 从表中删除指定的一条数据 */
	public void DeleteData() {
		/* 删除数据 */
		mSQLiteDatabase.execSQL("DELETE FROM" + TABLE_NAME + "WHERE _id="
				+ Integer.toString(miCount));

		miCount--;
		if (miCount < 0) {
			miCount = 0;
		}

		UpdataAdapter();
	}

	/* 更行试图显示 */
	public void UpdataAdapter() {
		// 获取数据库Phones的Cursor
		Cursor cur = mSQLiteDatabase.query(TABLE_NAME, new String[] { TABLE_ID,
				TABLE_NUM, TABLE_DATA }, null, null, null, null, null);

		miCount = cur.getCount();
		if (cur != null && cur.getCount() >= 0) {
			// ListAdapter是ListView和后台数据的桥梁
			ListAdapter adapter = new SimpleCursorAdapter(this,
			// 定义List中每一行的显示模板
			// 表示每一行包含两个数据项
					android.R.layout.simple_list_item_2,
					// 数据库的Cursor对象
					cur,
					// 数据库的Cursor对象
					new String[] { TABLE_NUM, TABLE_DATA },
					// 与NAME和NUMBER对应的Views
					new int[] { android.R.id.text1, android.R.id.text2 });
			/* 将adapter添加到m_ListView中 */
			m_ListView.setAdapter(adapter);
		}
	}

	/* 按键事件处理 */
	public boolean onKeyDown(int keyCode, KeyEvent event) {
		if (keyCode == KeyEvent.KEYCODE_BACK) {
			/* 关闭数据库(易忘) */
			mSQLiteDatabase.close();
			this.finish();
			return true;
		}
		return super.onKeyDown(keyCode, event);
	}

}


android SQLite数据库基本操作示例_第1张图片  8

  上面的测试数据8是 之前 创建的。。


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