android 记事本例子(sqlite增删改查)源码下载

【实例截图】

【核心代码】

package com.geolo.android;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Toast;

public class NotepadMain extends Activity {
    /** Called when the activity is first created. */
	LinearLayout mLinearLayout;
	ListView mListView; 
	DatabaseManage mDatabaseManage;
	private static long getId;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        createListView();
        //构造DatabaseManage对象
        mDatabaseManage = new DatabaseManage(this);
        //更新视图显示
        UpdataView();
       //为mListView视图添加setOnItemSelectedListener监听
        mListView.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener(){
			@Override
			public void onItemSelected(AdapterView<?> parent, View view,
					int position, long id) {
				getId = id;
			}
			@Override
			public void onNothingSelected(AdapterView<?> parent) {
				// 没有选中
				
			}});
        //为mListView视图添加监听
        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener(){
			@Override
			public void onItemClick(AdapterView<?> parent, View view,
					int position, long id) {
				// 对于选中的项进行处理
				//新建一个到查看界面的Intent对象
	    		Intent intent = new Intent();
	    		//新建一个传送参数的bundle对象
	    		Bundle bundle = new Bundle(); 
	    		//指定intent要启动的类
	    		intent.setClass(NotepadMain.this, NotepadView.class);
	    		//把参数id放到bundle中传送
	    		bundle.putLong("ID", id); 
	    		//让intent携带这个bundle
	    		intent.putExtras(bundle); 
	    		//启动一个新的Activity
	    		startActivity(intent);
	    		//清除bundle的参数
				bundle.clear();
	    		//关闭当前的Activity
	    		NotepadMain.this.finish();
			}});
    }
    
    //创建列表视图
    public void createListView(){
    	//创建LinearLayout布局对象
    	mLinearLayout = new LinearLayout(this);
    	//设置布局LinearLayout的属性
    	mLinearLayout.setOrientation(LinearLayout.VERTICAL);
    	mLinearLayout.setBackgroundColor(android.graphics.Color.BLACK);
    	//创建ListView对象
    	mListView = new ListView(this);
    	LinearLayout.LayoutParams param = new LinearLayout.LayoutParams(
    			                            LinearLayout.LayoutParams.FILL_PARENT, 
    			                            LinearLayout.LayoutParams.WRAP_CONTENT);
    	//设置列表的背景色
    	mListView.setBackgroundColor(Color.BLACK);
    	//添加mListView到mLinearLayout布局
    	mLinearLayout.addView(mListView , param);
    	//设置显示mLinearLayout布局
    	setContentView(mLinearLayout);
    }
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
    	menu.add(0,0,0,"添加");
    	menu.add(0,1,1,"删除");
    	menu.add(0,2,2,"退出");
    	return super.onCreateOptionsMenu(menu);
    }

    //删除指定数据
    public void deleteAssignData(){
    	try {
    		if(getId != 0){
    			mDatabaseManage.DeleteData(getId);
    			Toast.makeText(this, "删除成功", Toast.LENGTH_SHORT);
    			UpdataView();
    		}else{
    			Toast.makeText(this, "删除失败", Toast.LENGTH_SHORT);
        		UpdataView();
    		}
    	} catch (Exception e) {
    		Toast.makeText(this, "删除失败", Toast.LENGTH_SHORT);
    		UpdataView();
    		e.printStackTrace();
    	}
    }
    //更新视图显示
    public void UpdataView(){
    	mListView.setAdapter(mDatabaseManage.UpdataAdapter());
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item){
    	//得到当前选中的MenuItem的ID
    	int item_id = item.getItemId();
    	switch (item_id) {
    	//添加菜单事件
    	case 0:   
    		//新建一个到编辑界面的Intent对象
    		Intent intent = new Intent();
    		//新建一个传送参数的bundle对象
    		Bundle bundle = new Bundle(); 
    		//把参数id放到bundle中传送
    		bundle.putString("mode", "main");
    		//让intent携带这个bundle
    		intent.putExtras(bundle); 
    		//指定intent要启动的类
    		intent.setClass(NotepadMain.this, NotepadEditor.class);
    		//启动一个新的Activity
    		startActivity(intent);
    		//关闭当前的Activity
    		NotepadMain.this.finish();
    		break;
    		
    		//删除菜单事件
    	case 1:
    		deleteAssignData();
    		break;
    		
    		//退出菜单事件
    	case 2:
    		this.finish();
    		break;
    		
    	default:
    		break;
    	}
    	return super.onOptionsItemSelected(item);
    }
}