Android小程序-乐学成语收藏（三）

目标效果：



在学习时收藏成语，切换到收藏页面可以显示收藏过的成语，点击右边的红色五角星可以删除该成语。

1.新建CollectActivity.java页面和activity_collect.xml页面作为收藏页面。

activity_collect.xml页面：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/bg_ling"
tools:context=".GameActivity" >

<ListView
android:id="@+id/lvCollect"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>

</RelativeLayout>

2.新建MyDatabaseHelper.java页面创建收藏表存储收藏信息。
MyDatabaseHelper.java页面：

package cn.edu.bztc.happyidiom.db;

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

public class MyDatabaseHelper extends SQLiteOpenHelper {

public static final String DB_COLLECT_NAME = "collect.db";// 数据库名
public static final int COLLECT_VERSION = 1;// 数据库版本号
public static final String TABLE_COLLECT = "collect";// 表名
public static final String COLLECT_ID = "id";// id字段
public static final String COLLECT_NAME = "name";// 成语名称
public static final String COLLECT_PRO = "pronounce";// 成语发音
public static final String COLLECT_EXP = "explain";// 成语解释
public static final String COLLECT_ANT = "antonym";// 反义词
public static final String COLLECT_HOM = "homoionym";// 同义词
public static final String COLLECT_DER = "derivation";// 源自
public static final String COLLECT_EXA = "examples";// 例子

public static final String CREATE_COLLECT = "create table collect (id integer primary key autoincrement,name text,pronounce text,explain text,antonym text,homoionym text,derivation text,examples text)";

public MyDatabaseHelper(Context context) {
super(context, DB_COLLECT_NAME, null, COLLECT_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_COLLECT);// 执行创建数据库的SQL语句
}

@Override
public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
}

}

3.新建CollectDao.java页面作为收藏表的操作页面。
CollectDao.java页面：

package cn.edu.bztc.happyidiom.dao;

import java.util.ArrayList;
import java.util.List;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
import cn.edu.bztc.happyidiom.db.MyDatabaseHelper;
import cn.edu.bztc.happyidiom.entity.Animal;

public class CollectDao {
private static CollectDao collectDao;
SQLiteDatabase db;
MyDatabaseHelper mydatabaseHelper;
public CollectDao(Context context){
mydatabaseHelper=new MyDatabaseHelper(context);
}

public synchronized static CollectDao getInstance(Context context){
if(collectDao==null){
collectDao=new CollectDao(context);
}
return collectDao;
}

/*添加收藏*/
public void add(Animal animal) {
db=mydatabaseHelper.getWritableDatabase();
ContentValues value=new ContentValues();

value.put(MyDatabaseHelper.COLLECT_NAME,animal.getName());
value.put(MyDatabaseHelper.COLLECT_PRO,animal.getPronounce());
value.put(MyDatabaseHelper.COLLECT_EXP,animal.getExplain());
value.put(MyDatabaseHelper.COLLECT_ANT,animal.getAntonym());
value.put(MyDatabaseHelper.COLLECT_HOM,animal.getHomoionym());
value.put(MyDatabaseHelper.COLLECT_DER,animal.getDerivation());
value.put(MyDatabaseHelper.COLLECT_EXA,animal.getExamples());

db.insert(MyDatabaseHelper.TABLE_COLLECT,null,value);
value.clear();
}

/*从数据库读取所有的动物类成语*/
public List<Animal> getAllAnimals(List<Animal> list){
db=mydatabaseHelper.getReadableDatabase();
Cursor cursor=db.query("collect",null,null,null,null,null,null);

if(cursor.moveToNext()){
do{
Animal animal=new Animal();
animal.setId(cursor.getInt(cursor.getColumnIndex("id")));
animal.setName(cursor.getString(cursor.getColumnIndex("name")));
animal.setPronounce(cursor.getString(cursor.getColumnIndex("pronounce")));
animal.setAntonym(cursor.getString(cursor.getColumnIndex("antonym")));
animal.setHomoionym(cursor.getString(cursor.getColumnIndex("homoionym")));
animal.setDerivation(cursor.getString(cursor.getColumnIndex("derivation")));
animal.setExamples(cursor.getString(cursor.getColumnIndex("examples")));
animal.setExplain(cursor.getString(cursor.getColumnIndex("explain")));
list.add(animal);
}while(cursor.moveToNext());
}cursor.close();
return list;
}

/*根据id删除收藏信息*/
public void del(int id){
db=mydatabaseHelper.getWritableDatabase();
db.delete(mydatabaseHelper.TABLE_COLLECT,mydatabaseHelper.COLLECT_ID+"=?",new String[]{String.valueOf(id)});
}

}

4.创建CollectAdapter.java页面为适配器，配置数据源和ListView。
CollectAdapter.java页面：

package cn.edu.bztc.happyidiom.adapter;

import java.util.List;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import cn.edu.bztc.happyidiom.dao.CollectDao;
import cn.edu.bztc.happyidiom.entity.Animal;
import cn.edu.bztc.happyidiom.minterface.ChangeListData;
import cn.edu.bztc.happyidion.activity.CollectActivity;
import cn.edu.bztc.happyidion.activity.MainActivity;
import cn.edu.bztc.happyidion.activity.R;

public class CollectAdapter extends ArrayAdapter<Animal> {

private int resourceId;
private Context context;
private ChangeListData mChangeListData;

public CollectAdapter(Context context, int resource, List<Animal> objects) {
super(context, resource, objects);
this.context = context;
resourceId = resource;
}

public ChangeListData getChangeListData() {
return mChangeListData;
}

public void setChangeListData(ChangeListData mChangeListData) {
this.mChangeListData = mChangeListData;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
final Animal animal = getItem(position);// 获取当前项的Animal实例
View view;
ViewHolder viewHolder;
if (convertView == null) {// 判断是否第一次运行，如果是则进入，并将上下文环境保存进convertView
view = LayoutInflater.from(getContext()).inflate(resourceId, null);
viewHolder = new ViewHolder();
viewHolder.tvName = (TextView) view.findViewById(R.id.tvName);
viewHolder.btnDel = (ImageButton) view.findViewById(R.id.btnDel);
viewHolder.btnDel.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
/* 弹出提示框 */
showDialog();
}

/* 弹出提示框 */
private void showDialog() {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage("确定删除？");// 设置内容
/* 添加对话框中确定按钮和点击事件 */
builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
CollectDao collectDao = new CollectDao(context);
collectDao.del(animal.getId());
Toast.makeText(context, "删除成功", Toast.LENGTH_SHORT).show();
if (mChangeListData != null)
mChangeListData.changedata();
}
});
/* 添加对话框中取消按钮和点击事件 */
builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface arg0, int arg1) {
}
});
AlertDialog dialog = builder.create();// 获取dialog
dialog.show();// 显示对话框
}
});
view.setTag(viewHolder);
} else {// 如果不是第一次运行，convertView不为空，直接取出赋值给view
view = convertView;
viewHolder = (ViewHolder) view.getTag();
}
viewHolder.tvName.setText(animal.getName());// 显示成语
return view;
}

class ViewHolder {
TextView tvName;
ImageButton btnDel;
}
}

5.新建ChangeListData.java接口，用于删除时调用。
ChangeListData.java页面：

package cn.edu.bztc.happyidiom.minterface;

public interface ChangeListData {
public void changedata();
}

6.CollectActivity.java页面设置ListView的点击事件。
CollectActivity.java页面：

package cn.edu.bztc.happyidion.activity;

import java.util.ArrayList;
import java.util.List;

import cn.edu.bztc.happyidiom.adapter.CollectAdapter;
import cn.edu.bztc.happyidiom.dao.CollectDao;
import cn.edu.bztc.happyidiom.entity.Animal;
import cn.edu.bztc.happyidiom.minterface.ChangeListData;
import cn.edu.bztc.happyidiom.util.DialogUtil;

import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;

public class CollectActivity extends Activity {

private List<Animal> collectList = new ArrayList<Animal>();
private CollectDao collectDao;
private ListView lvCollect;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_collect);

initAnimals();
lvCollect = (ListView) findViewById(R.id.lvCollect);
final CollectAdapter collectAdapter = new CollectAdapter(this,
R.layout.collect_item, collectList);
lvCollect.setAdapter(collectAdapter);

lvCollect.setOnItemClickListener(new OnItemClickListener() {

@Override
public void onItemClick(AdapterView<?> adapterView, View view,
int position, long id) {
Animal animal = collectList.get(position);
/* 定义对话框中提示语句 */
String result = animal.getName() + "\n" + animal.getPronounce()
+ "\n【解释】：" + animal.getExplain()
+ "\n【近义词】："+ animal.getHomoionym()
+ "\n【反义词】："+ animal.getAntonym()
+ "\n【来源】："+ animal.getDerivation()
+ "\n【示例】："+ animal.getExamples();
DialogUtil.showDialog(result, CollectActivity.this);
}
});
collectAdapter.setChangeListData(new ChangeListData() {

/*刷新ListView*/
@Override
public void changedata() {
collectList.clear();
collectDao.getAllAnimals(collectList);
collectAdapter.notifyDataSetChanged();
}
});
}

/* 获取数据库中的收藏集合 */
private void initAnimals() {
collectDao = CollectDao.getInstance(this);
collectDao.getAllAnimals(collectList);

}

}

7.修改MainActivity.java页面，一是创建了一个数据库存储收藏表，二是更改了TabHost子页面的绑定方式，原先那种运行程序只会在一开始创建页面，之后更改页面信息都不会再动态刷新，更改后收藏列表可以显示出来。

MainActivity.java页面：

package cn.edu.bztc.happyidion.activity;

import cn.edu.bztc.happyidiom.db.MyDatabaseHelper;
import android.app.TabActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.Window;
import android.widget.TabHost;

public class MainActivity extends TabActivity {

private TabHost tabHost;// 导航栏控件

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);// 取消标题栏
setContentView(R.layout.activity_main);

createCollectDatabase();
tabHost = getTabHost(); // 获取TabHost实例
/* 一个Tab对应一个name名称，一个标题，一个图标，yigeActivity页面 */
// addTab("study",R.string.title_study,R.drawable.study,StudyActivity.class);
// addTab("search",R.string.title_search,R.drawable.search,SearchActivity.class);
// addTab("game",R.string.title_game,R.drawable.game,GameActivity.class);
// addTab("save",R.string.title_save,R.drawable.save,CollectActivity.class);
// addTab("help",R.string.title_help,R.drawable.help,StudyActivity.class);

tabHost.addTab(tabHost.newTabSpec("study")
.setIndicator("学习",getResources().getDrawable(R.drawable.study))
.setContent(new Intent(this, StudyActivity.class)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)));
tabHost.addTab(tabHost.newTabSpec("search")
.setIndicator("搜索",getResources().getDrawable(R.drawable.search))
.setContent(new Intent(this, SearchActivity.class)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)));
tabHost.addTab(tabHost.newTabSpec("game")
.setIndicator("游戏",getResources().getDrawable(R.drawable.game))
.setContent(new Intent(this, GameActivity.class)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)));
tabHost.addTab(tabHost.newTabSpec("save")
.setIndicator("收藏",getResources().getDrawable(R.drawable.save))
.setContent(new Intent(this, CollectActivity.class)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)));
tabHost.addTab(tabHost.newTabSpec("help")
.setIndicator("帮助",getResources().getDrawable(R.drawable.help))
.setContent(new Intent(this, StudyActivity.class)
.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)));

}

/* 创建收藏数据库 */
private void createCollectDatabase() {
MyDatabaseHelper mydatabaseHelper = new MyDatabaseHelper(
MainActivity.this);
mydatabaseHelper.getWritableDatabase();
}

/* 定义每个Tab的显示内容 */
private void addTab(String tag, int title_introduction, int title_icon,
Class ActivityClass) {
tabHost.addTab(tabHost
.newTabSpec(tag)
.setIndicator(getString(title_introduction),
getResources().getDrawable(title_icon))
.setContent(new Intent(this, ActivityClass)));
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}

8.程序源码：点击打开链接

9.运行就可以显示目标效果了。