android listview综合使用示例_结合数据库操作和listitem单击长按等事件处理

本示例说明:

1.自定义listview条目样式,自定义listview显示列数的多少,灵活与数据库中字段绑定.

2.实现对DB的增删改查,并且操作后listview自动刷新.

3.响应用户操作点击事件,示例中展示单击时取出主键Id和其他内容.

4.响应用户操作长按事件,示例中展示长按时根据主键Id来编辑和删除数据.

5.表现层与数据处理层分开,不依赖于cursor(使用cursor不易表现和业务分离),支持接口编程.

6.使用数据库处理框架AHibernate灵活操作sqlite数据库,详见: http://blog.csdn.net/lk_blog/article/details/7455992

 

本示例效果图:

list.xml:

<?xml version="1.0" encoding="UTF-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:id="@+id/child"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    android:background="#E3D25E"

    android:orientation="horizontal" >



    <!-- 若想隐藏id加入此属性: android:visibility="gone",这样做有点类似于Html中hidden域 -->



    <TextView

        android:id="@+id/idTo"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:textColor="#ff0000" />



    <TextView

        android:id="@+id/nameTo"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:paddingBottom="5px"

        android:paddingLeft="50px"

        android:paddingTop="5px"

        android:text="No data"

        android:textColor="#0000ff"

        android:textSize="20sp" />



    <TextView

        android:id="@+id/ageTo"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:paddingBottom="5px"

        android:paddingLeft="50px"

        android:paddingTop="5px"

        android:text="No data"

        android:textColor="#00ff00"

        android:textSize="20sp" />



</LinearLayout>

2.MainActivity.java:

package com.tgb.lk.listview;



import java.util.List;

import java.util.Map;



import com.tgb.lk.demo.dao.StudentDao;

import com.tgb.lk.demo.dao.impl.StudentDaoImpl;

import com.tgb.lk.demo.model.Student;



import com.tgb.lk.listview.R;

import android.app.Activity;

import android.content.Context;

import android.os.Bundle;

import android.text.TextUtils;

import android.view.ContextMenu;

import android.view.MenuItem;

import android.view.View;

import android.view.ContextMenu.ContextMenuInfo;

import android.view.View.OnClickListener;

import android.widget.AdapterView;

import android.widget.Button;

import android.widget.ListView;

import android.widget.SimpleAdapter;

import android.widget.TextView;

import android.widget.Toast;

import android.widget.AdapterView.AdapterContextMenuInfo;

import android.widget.AdapterView.OnItemClickListener;

/**

 * 欢迎访问我的博客进行对代码交流: http://blog.csdn.net/lk_blog

 * 数据库处理使用AHibernate框架,详见:http://blog.csdn.net/lk_blog/article/details/7455992

 * @author likun

 */

public class MainActivity extends Activity {

    private static final int ITEM_MODIFY = 1;

    private static final int ITEM_DELETE = 2;



    // 定义接口

    private StudentDao dao = null;

    private ListView lv = null;



    @Override

    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.main);



        // 添加

        Button btnAdd = (Button) findViewById(R.id.btnAdd);

        btnAdd.setOnClickListener(listener);

        // 显示前3条数据

        Button btnShow = (Button) findViewById(R.id.btnShow);

        btnShow.setOnClickListener(listener);

        // 删除数据

        Button btnClear = (Button) findViewById(R.id.btnClear);

        btnClear.setOnClickListener(listener);



        lv = (ListView) findViewById(R.id.lvStudent);

        // 设置在条目上单击监听器

        lv.setOnItemClickListener(itemListener);

        // 设置长按事件

        registerForContextMenu(lv);



        // 显示所有数据

        showData(-1);

    }



    // 显示数据,num小于等于0时显示所有数据,num大于0时显示前N条.

    private void showData(int num) {

        dao = (dao == null ? new StudentDaoImpl(this) : dao);

        List<Map<String, String>> data = null;

        if (num <= 0) { // 显示所有学生,调用dao层接口

            data = dao.queryAllStudent();

        } else {// 显示前N个学生,调用dao层接口

            data = dao.queryTopN(num);

        }

        SimpleAdapter adapter = buildListAdapter(this, data);

        lv.setAdapter(adapter);



    }



    // 构建adapter.

    public SimpleAdapter buildListAdapter(Context context,

            List<Map<String, String>> data) {

        SimpleAdapter adapter = new SimpleAdapter(context, data, R.layout.list,

                new String[] { "_id", "name", "age" }, new int[] { R.id.idTo,

                        R.id.nameTo, R.id.ageTo });

        return adapter;

    }



    // 初始化数据

    OnClickListener listener = new OnClickListener() {

        @Override

        public void onClick(View v) {

            dao = (dao == null ? new StudentDaoImpl(MainActivity.this) : dao);

            switch (v.getId()) {

            case R.id.btnAdd:

                // 添加学生

                Student student1 = new Student();

                student1.setName("lk");

                student1.setAge(26);

                dao.insert(student1);



                Student student2 = new Student();

                student2.setName("cls");

                student2.setAge(26);

                dao.insert(student2);



                Student student3 = new Student();

                student3.setName("lb");

                student3.setAge(27);

                dao.insert(student3);

                showData(-1);



                break;

            case R.id.btnShow:

                // 显示前3条数据

                showData(3);

                break;

            case R.id.btnClear:

                // 删除所有数据

                dao.deleteData();



                // 显示所有数据

                showData(-1);

                break;

            default:

                break;

            }



        }

    };



    // 条目上单击处理方法.

    OnItemClickListener itemListener = new OnItemClickListener() {

        @Override

        public void onItemClick(AdapterView<?> parent, View view, int position,

                long id) {

            // 这里的view是我们在list.xml中定义的LinearLayout对象.

            // 所以可以通过findViewById方法可以找到list.xml中定义的它的子对象,如下:

            TextView stuId = (TextView) view.findViewById(R.id.idTo);

            TextView stuName = (TextView) view.findViewById(R.id.nameTo);

            TextView stuAge = (TextView) view.findViewById(R.id.ageTo);



            toastShow("学号:" + stuId.getText().toString() + "; 姓名:"

                    + stuName.getText().toString() + "; 年龄:"

                    + stuAge.getText().toString());

        }

    };



    // 封装Toast,一方面调用简单,另一方面调整显示时间只要改此一个地方即可.

    public void toastShow(String text) {

        Toast.makeText(MainActivity.this, text, 1000).show();

    }



    // 长按时显示的菜单

    @Override

    public void onCreateContextMenu(ContextMenu menu, View v,

            ContextMenuInfo menuInfo) {

        menu.setHeaderTitle("请选择操作");

        menu.add(0, ITEM_MODIFY, 0, "编辑");

        menu.add(0, ITEM_DELETE, 1, "删除");

    }



    // 响应编辑和删除事件处理

    public boolean onContextItemSelected(MenuItem item) {

        AdapterContextMenuInfo info = (AdapterContextMenuInfo) item

                .getMenuInfo();

        // info.targetView得到list.xml中的LinearLayout对象.

        String stuId = ((TextView) info.targetView.findViewById(R.id.idTo))

                .getText().toString();

        if (!TextUtils.isEmpty(stuId)) {

            int id = Integer.parseInt(stuId);

            dao = (dao == null ? new StudentDaoImpl(this) : dao);

            switch (item.getItemId()) {

            case ITEM_MODIFY:

                // 编辑数据

                toastShow("编辑" + stuId);

                // 此方法定义在AHibernate中.更多使用示例见http://blog.csdn.net/lk_blog/article/details/7455992

                Student student = dao.get(id);

                student.setName("李坤");

                student.setAge(26);

                dao.update(student); // 此方法定义在AHibernate中.

                break;

            case ITEM_DELETE:

                // 删除数据

                toastShow("删除" + stuId);

                dao.delete(id);// 此方法定义在AHibernate中.

                break;

            default:

                break;

            }

        }

        showData(-1);

        return false;

    }



}

3.数据库处理层:StudentDaoImpl.java:

package com.tgb.lk.demo.dao.impl;



import java.util.List;

import java.util.Map;



import com.tgb.lk.ahibernate.dao.impl.BaseDaoImpl;

import com.tgb.lk.demo.dao.StudentDao;

import com.tgb.lk.demo.model.Student;

import com.tgb.lk.demo.util.DBHelper;

import android.content.Context;



//本文数据库处理引用jar包AHibernate处理.

//AHibernate的详细使用教程示例地址: http://blog.csdn.net/lk_blog/article/details/7455992

//AHibernate源码交流地址: http://blog.csdn.net/lk_blog/article/details/7456125

//AHibernate jar包下载及源代码下载地址: http://download.csdn.net/detail/lk_blog/4222048

public class StudentDaoImpl extends BaseDaoImpl<Student> implements StudentDao {

    public StudentDaoImpl(Context context) {

        super(new DBHelper(context));

    }



    // 返回一个List,List中的对象是以sql中的列的小写形式为key的Map.(本例中 _id,name,age为key)

    public List<Map<String, String>> queryAllStudent() {

        String sql = "select _id, name,age from t_student";

        return super.query2MapList(sql, null);

    }



    // 返回一个List,List中的对象是以sql中的列的小写形式为key的Map.(本例中 _id,name,age为key)

    public List<Map<String, String>> queryTopN(int num) {

        String sql = "select _id, name,age from t_student limit ?";

        return super.query2MapList(sql, new String[] { String.valueOf(num) });

    }



    public void deleteData() {

        String sql = "delete from t_student";

        super.execSql(sql, null);

    }

}

本示例源代码下载地址:  http://download.csdn.net/detail/lk_blog/4278055

 

文章转载于 http://blog.csdn.net/lk_blog/article/details/7537200