玩家信息管理（SQLite+Fragment加强）

本文出自：http://blog.csdn.net/dt235201314/article/details/50463194

一丶效果演示：

二丶需求分析

1.设计简单玩家包涵以下属性

GamePlay：

关卡

分数

游戏ID

2.实现游戏玩家数据的增删改

三丶功能设计

1.展现玩家基本数据

2.分数降序排列

3.管理员可增删改玩家信息

四丶技术实现

1.SQLitem完成数据的基本功能

2.Activity和Fragment交互

3ListView显示玩家信息

五丶代码展示

1.创建entity文件夹存放实体类GamePlayer.java并创建get set toSring方法

public class GamePlayer {    private String player;    private int score;    private int level;    private int id;    public GamePlayer() {    }    public GamePlayer(String player, int score, int level) {        this.player = player;        this.score = score;        this.level = level;    }    public GamePlayer(String player, int score, int level, int id) {        this.player = player;        this.score = score;        this.level = level;        this.id = id;    }    public String getPlayer() {        return player;    }    public void setPlayer(String player) {        this.player = player;    }    public int getScore() {        return score;    }    public void setScore(int score) {        this.score = score;    }    public int getLevel() {        return level;    }    public void setLevel(int level) {        this.level = level;    }    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    @Override    public String toString() {        return "GamePlayer{" +                "player='" + player + '\'' +                ", score=" + score +                ", level=" + level +                ", id=" + id +                '}';    }}

2.创建db文件夹存放数据库部分（DatabaseAdapter DatabaseHelper GameMetaData）

GameMetaData     数据库元数据

public final class GameMetaData {    private GameMetaData() {    }    //定义表 和 列字段名    public static abstract class GamePlay implements BaseColumns {        public static final String TABLE_NAME = "player_table";        public static final String PLAYER = "player";        public static final String SCORE = "score";        public static final String LEVEL= "level";    }}

DatabaseAdapter 数据库操作

public class DatabaseAdapter {    private DatabaseHelper dbHelper;    public DatabaseAdapter(Context context) {        dbHelper = new DatabaseHelper(context);    }    //添加操作    public void add(GamePlayer gamePlayer) {        SQLiteDatabase db = dbHelper.getWritableDatabase();        ContentValues values = new ContentValues();        values.put(GameMetaData.GamePlay.PLAYER, gamePlayer.getPlayer());        values.put(GameMetaData.GamePlay.SCORE, gamePlayer.getScore());        values.put(GameMetaData.GamePlay.LEVEL, gamePlayer.getLevel());        db.insert(GameMetaData.GamePlay.TABLE_NAME, null, values);        db.close();    }    //删除操作    public void delete(int id) {        SQLiteDatabase db = dbHelper.getWritableDatabase();        String whereClause = GameMetaData.GamePlay._ID + "=?";        String[] whereArgs = {String.valueOf(id)};        db.delete(GameMetaData.GamePlay.TABLE_NAME, whereClause, whereArgs);        db.close();    }    //更新操作    public void update(GamePlayer gamePlayer) {        SQLiteDatabase db = dbHelper.getWritableDatabase();        ContentValues values = new ContentValues();        values.put(GameMetaData.GamePlay.PLAYER, gamePlayer.getPlayer());        values.put(GameMetaData.GamePlay.SCORE, gamePlayer.getScore());        values.put(GameMetaData.GamePlay.LEVEL, gamePlayer.getLevel());        String whereClause = GameMetaData.GamePlay._ID + "=?";        String[] whereArgs = {String.valueOf(gamePlayer.getId())};        db.update(GameMetaData.GamePlay.TABLE_NAME, values, whereClause, whereArgs);        db.close();    }    //查询    public GamePlayer findById(int id) {        SQLiteDatabase db = dbHelper.getReadableDatabase();        Cursor cursor = db.query(true, GameMetaData.GamePlay.TABLE_NAME, null, GameMetaData.GamePlay._ID + "=?",                new String[]{String.valueOf(id)}, null, null, null, null);        GamePlayer gamePlayer = null;        if (cursor.moveToNext()) {            gamePlayer = new GamePlayer();            gamePlayer.setPlayer(cursor.getString(cursor.getColumnIndexOrThrow(GameMetaData.GamePlay.PLAYER)));            gamePlayer.setId(cursor.getInt(cursor.getColumnIndexOrThrow(GameMetaData.GamePlay._ID)));            gamePlayer.setLevel(cursor.getInt(cursor.getColumnIndexOrThrow(GameMetaData.GamePlay.LEVEL)));            gamePlayer.setScore(cursor.getInt(cursor.getColumnIndexOrThrow(GameMetaData.GamePlay.SCORE)));        }        cursor.close();        db.close();        return gamePlayer;    }    public ArrayList<GamePlayer> findAll() {        String sql = "select _id,player,score,level from player_table order by score desc";        SQLiteDatabase db = dbHelper.getReadableDatabase();        Cursor c = db.rawQuery(sql, null);        ArrayList<GamePlayer> gamePlayers = new ArrayList<>();        GamePlayer gamePlayer = null;        while (c.moveToNext()) {            gamePlayer = new GamePlayer();            gamePlayer.setPlayer(c.getString(c.getColumnIndexOrThrow(GameMetaData.GamePlay.PLAYER)));            gamePlayer.setId(c.getInt(c.getColumnIndexOrThrow(GameMetaData.GamePlay._ID)));            gamePlayer.setScore(c.getInt(c.getColumnIndexOrThrow(GameMetaData.GamePlay.SCORE)));            gamePlayer.setLevel(c.getInt(c.getColumnIndexOrThrow(GameMetaData.GamePlay.LEVEL)));            gamePlayers.add(gamePlayer);        }        c.close();        db.close();        return gamePlayers;    }    //查询总记录数    public int getCount() {        int count = 0;        String sql = "select count(_id) from player_table";        SQLiteDatabase db = dbHelper.getReadableDatabase();        Cursor c = db.rawQuery(sql, null);        c.moveToFirst();        count = c.getInt(0);//取第一条        c.close();        db.close();        return count;    }}

DatabaseHelper

public class DatabaseHelper extends SQLiteOpenHelper {    private static final String DB_NAME = "game.db";    private static final int VERSION = 1;    //创建表 sql    private static final String CREATE_TABLE_PLAYER = "CREATE TABLE IF NOT EXISTS player_table(" +            "_id INTEGER PRIMARY KEY AUTOINCREMENT," +            "player TEXT,score INTEGER,level INTEGER)";    //删除表    private static final String DROP_TABLE_PLAYER = "DROP TABLE IF EXISTS player_table";    public DatabaseHelper(Context context) {        super(context, DB_NAME, null, VERSION);    }    @Override    public void onCreate(SQLiteDatabase db) {        db.execSQL(CREATE_TABLE_PLAYER);    }    @Override    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {        db.execSQL(DROP_TABLE_PLAYER);        db.execSQL(CREATE_TABLE_PLAYER);    }}

3.以Fragment的形式呈现并完善功能，创建Fragment存放用到的Fragment（AddFragment GamePlayFragment UpdateFragment）

AddFragment用于完成添加游戏玩家功能，这里利用弹窗的形式，和菜单

activity.xml为空

menu_main1229

<menu xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools" tools:context=".Main1229Activity">    <item android:id="@+id/add" android:title="@string/add"        android:icon="@android:drawable/ic_menu_add"        android:orderInCategory="100" app:showAsAction="always" /></menu>

AddFragment

public class AddFragment extends DialogFragment {    private AddFragmentListener addFragmentListener;    //定义接口，方便与activity交互 ：    public static interface AddFragmentListener {        public void add(GamePlayer gamePlayer);    }    public AddFragment(){    }    //获取 主页面的activity    @Override    public void onAttach(Activity activity) {        super.onAttach(activity);        try {            addFragmentListener = (AddFragmentListener) activity;        } catch (ClassCastException e) {            e.printStackTrace();        }    }    //保证 activity 给 fragment 传参时，旋转屏幕参数不丢失    public static AddFragment newInstance() {        AddFragment frag = new AddFragment();        return frag;    }        @Override    public Dialog onCreateDialog(Bundle savedInstanceState) {        //定义一个对话框视图        final View view = LayoutInflater.from(getActivity()).inflate(R.layout.create_game_dialog, null);        return new AlertDialog.Builder(getActivity())                .setIcon(android.R.drawable.ic_input_add)                .setView(view)                .setTitle("新增游戏玩家")                .setPositiveButton("保存",                        new DialogInterface.OnClickListener() {                            public void onClick(DialogInterface dialog, int whichButton) {                                //获取界面 组件对象                                EditText et_player = (EditText) view.findViewById(R.id.editText2_player);                                EditText et_score = (EditText) view.findViewById(R.id.editText_cscore);                                EditText et_level = (EditText) view.findViewById(R.id.edit_level);                                //接收用户的输入填充对象                                GamePlayer gamePlayer = new GamePlayer();                                gamePlayer.setPlayer(et_player.getText().toString());                                gamePlayer.setScore(Integer.parseInt(et_score.getText().toString()));                                gamePlayer.setLevel(Integer.parseInt(et_level.getText().toString()));                                addFragmentListener.add(gamePlayer);//调用activity方法 进行数据库添加操作                                dialog.dismiss();                            }                        }                )                .setNegativeButton("取消", new DialogInterface.OnClickListener() {                    public void onClick(DialogInterface dialog, int which) {                        dialog.dismiss();//隐藏对话框                    }                }).create();    }}

create_game_dialog.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    android:weightSum="1">    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/editText2_player"        android:hint="请输入玩家名称"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/editText_cscore"        android:hint="请输入玩家分数"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/edit_level"        android:hint="请输入玩家关卡数"        /></LinearLayout>

GamePlayFragment 完成玩家信息的现实及触发更改等内容

Fragment_game_play.xml

<FrameLayout 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"    tools:context="com.jin.administrator.my1229application.fragment.GamePlayFragment">    <!--数据列表显示容器-->    <ListView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/listView"        android:layout_gravity="center"        android:choiceMode="none"        /></FrameLayout>

game_player_list_item_layout.xml(显示玩家信息数据)

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    >    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceSmall"        android:text="序号："        android:id="@+id/textView" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceSmall"        android:text="玩家："        android:id="@+id/textView2"        android:layout_below="@+id/textView"        android:layout_alignParentLeft="true"        android:layout_alignParentStart="true" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceSmall"        android:text="分数："        android:id="@+id/textView3"        android:layout_below="@+id/textView2"        android:layout_alignParentLeft="true"        android:layout_alignParentStart="true" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textAppearance="?android:attr/textAppearanceSmall"        android:text="关卡:"        android:id="@+id/textView4"        android:layout_below="@+id/textView3"        android:layout_alignParentLeft="true"        android:layout_alignParentStart="true" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="not data"        android:textAppearance="?android:attr/textAppearanceSmall"        android:id="@+id/textView_id"        android:layout_alignParentTop="true"        android:layout_toRightOf="@+id/textView"        android:layout_toEndOf="@+id/textView" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="not data"        android:textAppearance="?android:attr/textAppearanceSmall"        android:id="@+id/textView_player"        android:layout_below="@+id/textView"        android:layout_toRightOf="@+id/textView"        android:layout_toEndOf="@+id/textView" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="not data"        android:textAppearance="?android:attr/textAppearanceSmall"        android:id="@+id/textView_score"        android:layout_below="@+id/textView2"        android:layout_toRightOf="@+id/textView2"        android:layout_toEndOf="@+id/textView2" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="not data"        android:textAppearance="?android:attr/textAppearanceSmall"        android:id="@+id/textView_level"        android:layout_toRightOf="@+id/textView3"        android:layout_toEndOf="@+id/textView3"        android:layout_below="@+id/textView_score"/></RelativeLayout>

listview_content_mrnu.xml（弹窗上面的menu）

<?xml version="1.0" encoding="utf-8"?><menu xmlns:android="http://schemas.android.com/apk/res/android">    <item android:id="@+id/delete_menu"        android:orderInCategory="100"        android:title="删除"        android:icon="@android:drawable/ic_menu_delete"/>    <item android:id="@+id/update_menu"        android:orderInCategory="100"        android:title="修改"        android:icon="@android:drawable/ic_menu_edit"/></menu>

GamePlayFragment

public class GamePlayFragment extends Fragment {    //适配器对象    GamePlayerAdapter gamePlayerAdapter;    //接口对象    private GamePlayerFragmentListener gamePlayerFragmentListener;    //定义接口    public static interface GamePlayerFragmentListener {        public void showGamePlayerFragment();//作用：显示列表 界面        public void showUpdateFragment(int id);//作用：更新数据的  从当前页面到更新页面，需要将本页的id带到更新页面上去 界面        public void delete(int id);        public ArrayList<GamePlayer> findAll();    }    //保证 activity 给 fragment 传参时，旋转屏幕参数不丢失    public static GamePlayFragment newInstance() {        GamePlayFragment fragment = new GamePlayFragment();        return fragment;    }    public GamePlayFragment(){    }    //获取 主页面的activity    @Override    public void onAttach(Activity activity) {        super.onAttach(activity);        try {            gamePlayerFragmentListener = (GamePlayerFragmentListener) activity;        } catch (ClassCastException e) {            e.printStackTrace();        }    }    /**************长按 每个item 时弹出菜单 ***********************************/    /**     * 创建 菜单项     */    @Override    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {        super.onCreateContextMenu(menu, v, menuInfo);        menu.setHeaderTitle("修改/删除");//菜单标题        menu.setHeaderIcon(android.R.drawable.ic_menu_edit);        //实例化 菜单项        getActivity().getMenuInflater().inflate(R.menu.listview_context_menu, menu);    }    @Override    public boolean onContextItemSelected(MenuItem item) {        switch (item.getItemId()) {            case R.id.delete_menu:                //获取菜单 信息对象                AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();                //获取前当前item的指定组件，  targetView ：当前点击的item视图                TextView textView_id = (TextView) info.targetView.findViewById(R.id.textView_id);                //获取组件上的内容，即id                int id = Integer.parseInt(textView_id.getText().toString());                //调用 activity的删除方法，删除指定的 id 数据                gamePlayerFragmentListener.delete(id);                //重新查询视图列表数据                changeData();                break;            case R.id.update_menu:                info = (AdapterView.AdapterContextMenuInfo) item.getMenuInfo();                textView_id = (TextView) info.targetView.findViewById(R.id.textView_id);                id = Integer.parseInt(textView_id.getText().toString());                //调用 activity的更新方法，显示更新的视图                gamePlayerFragmentListener.showUpdateFragment(id);                break;        }        return super.onContextItemSelected(item);    }    /************************显示列表 fragment 实例会调以下方法*************************/    /**     * 在这里实例化 适配器对象,并填充数据     */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        //从数据库中获取列表数据        ArrayList<GamePlayer> gamePlayers = gamePlayerFragmentListener.findAll();        //实例化 适配器        gamePlayerAdapter = new GamePlayerAdapter(getActivity(), gamePlayers);    }    /**     * 自定义 listView布局     */    @Override    public View onCreateView(LayoutInflater inflater, ViewGroup container,                             Bundle savedInstanceState) {        //实例化 fragment布局        View view = inflater.inflate(R.layout.fragment_game_play, container, false);        ListView listView = (ListView) view.findViewById(R.id.listView);        //注册上下文，因为长按时，要弹出菜单       registerForContextMenu(listView);        //        自定义布局        listView.setAdapter(gamePlayerAdapter);//设置 适配器        return view;    }    //自定义适配器    private static class GamePlayerAdapter extends BaseAdapter {        private Context context;        //列表 数据        private ArrayList<GamePlayer> gamePlayers;        //重新设置        public void setGamePlayers(ArrayList<GamePlayer> gamePlayers) {            this.gamePlayers = gamePlayers;        }        public GamePlayerAdapter(Context context, ArrayList<GamePlayer> gamePlayers) {            this.context = context;            this.gamePlayers = gamePlayers;        }        @Override        public int getCount() {            return gamePlayers.size();        }        @Override        public Object getItem(int position) {            return gamePlayers.get(position);        }        @Override        public long getItemId(int position) {            return position;        }        @Override        public View getView(int position, View convertView, ViewGroup parent) {            //节省性能,使用ViewHolder减少对象的查找            ViewHolder vh = null;            if (convertView == null) {//convertView:缓存item  减少对象的创建                //实例化 item 布局                convertView=LayoutInflater.from(context).inflate(R.layout.game_player_list_item_layout, null);                vh = new ViewHolder();                vh.tv_id = (TextView) convertView.findViewById(R.id.textView_id);                vh.tv_player = (TextView) convertView.findViewById(R.id.textView_player);                vh.tv_score = (TextView) convertView.findViewById(R.id.textView_score);                vh.tv_level = (TextView) convertView.findViewById(R.id.textView_level);                convertView.setTag(vh);            } else {                vh = (ViewHolder) convertView.getTag();            }            //组件数据填充            GamePlayer g = gamePlayers.get(position);            vh.tv_id.setText(String.valueOf(g.getId()));            vh.tv_player.setText(g.getPlayer());            vh.tv_score.setText(String.valueOf(g.getScore()));            vh.tv_level.setText(String.valueOf(g.getLevel()));            return convertView;        }    }    //用于保存每一次查找的组件，避免下次重复查找    private static class ViewHolder {        TextView tv_id;        TextView tv_player;        TextView tv_score;        TextView tv_level;    }    //重新查询数据    public void changeData() {        //从数据库查询数据，并填充到适配器中        gamePlayerAdapter.setGamePlayers(gamePlayerFragmentListener.findAll());        //让适配器重新加载数据 ，通知视内容更变        gamePlayerAdapter.notifyDataSetChanged();    }    /**     * 销毁时，置空     */    @Override    public void onDetach() {        super.onDetach();        gamePlayerFragmentListener = null;    }}

UpdateFragment （完成数据的更新）

fragment_update.xml

<RelativeLayout    android:id="@+id/relative_layout"    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"    tools:context="Fragments.UpdateFragment"    >    <TextView        android:id="@+id/textView1_id"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_gravity="left|top"        android:text="序号:"/>    <TextView        android:id="@+id/textView1_player"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_below="@+id/textView1_id"        android:text="玩家："        />    <EditText        android:id="@+id/editText2_player"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_toRightOf="@+id/textView1_player"        android:layout_alignTop="@+id/textView1_player"        android:layout_alignBottom="@+id/textView1_player"        android:hint="请输入玩家名称"        />    <TextView        android:id="@+id/textView1_score"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_below="@+id/editText2_player"        android:text="分数:"/>    <EditText        android:id="@+id/editText2_score"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@+id/editText2_player"        android:layout_toRightOf="@+id/textView1_player"        android:hint="请输入玩家分数"        />    <TextView        android:id="@+id/textView1_level"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_below="@+id/editText2_score"        android:text="关卡:"/>    <EditText        android:id="@+id/editText2_level"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@+id/editText2_score"        android:layout_toRightOf="@+id/textView1_player"        android:hint="请输入关卡数"        />    <TextView        android:id="@+id/textView2_id"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_alignParentTop="true"        android:layout_toRightOf="@+id/textView1_id"/>    <TextView        android:id="@+id/textView_into"        android:layout_width="wrap_content"        android:layout_height="50dp"        android:gravity="center"        android:textSize="20sp"        android:layout_alignParentBottom="true"        android:layout_marginBottom="115dp"        android:text="提示：这里为更新信息"/>    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:orientation="horizontal">        <Button            android:id="@+id/button_save"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_alignParentBottom="true"            android:layout_weight="1"            android:text="更新"            />        <Button            android:id="@+id/button_cancel"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_alignBottom="@+id/button_save"            android:layout_weight="1"            android:text="取消"            />    </LinearLayout></RelativeLayout>

UpdateFragment

public class UpdateFragment extends Fragment implements View.OnClickListener {    private EditText et_player;    private EditText et_score;    private EditText et_level;    private GamePlayer gamePlayer;    //activity 实现的接口    private  UpdateFragmentListener updateFragmentListener;    //定义接口    public static interface UpdateFragmentListener {        public GamePlayer findById(int id); //作用：查询        public void update(GamePlayer gamePlayer);//作用：更新    }    @Override    public void onAttach(Activity activity) {        super.onAttach(activity);        try {            updateFragmentListener = (UpdateFragmentListener) activity;        } catch (ClassCastException e) {            e.printStackTrace();        }    }    //保证 activity 给 fragment 传参时，旋转屏幕参数不丢失    public static UpdateFragment newInstance(int id) {        UpdateFragment updateFragment = new UpdateFragment();        Bundle b = new Bundle();        b.putInt("id", id);        updateFragment.setArguments(b);//保存传入的参数        return updateFragment;    }    /*******************实例化 fragment 时，调用以下方法****************************/    /**     * 实例化时 查询数据     */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        int id = getArguments().getInt("id");        //activity 从数据库中查询指定id的对象数据        gamePlayer = updateFragmentListener.findById(id);    }    @Override    public View onCreateView(LayoutInflater inflater, ViewGroup container,                             Bundle savedInstanceState) {        //实例化 fragment布局        View view = inflater.inflate(R.layout.fragment_update, container, false);        //查找界面 组件        TextView tv_id = (TextView) view.findViewById(R.id.textView2_id);        et_player = (EditText) view.findViewById(R.id.editText2_player);        et_score = (EditText) view.findViewById(R.id.editText2_score);        et_level = (EditText) view.findViewById(R.id.editText2_level);        //界面按钮        Button button_save = (Button) view.findViewById(R.id.button_save);        Button button_cancel = (Button) view.findViewById(R.id.button_cancel);        //注册监听事件        button_save.setOnClickListener(this);        button_cancel.setOnClickListener(this);        //组件内容填充        tv_id.setText(String.valueOf(gamePlayer.getId()));        et_player.setText(gamePlayer.getPlayer());        et_score.setText(String.valueOf(gamePlayer.getScore()));        et_level.setText(String.valueOf(gamePlayer.getLevel()));        return view;    }    /**************** fragment 上按钮的监听事件 *************************/    /**     * 按钮 监听事件     *     * @param v     */    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.button_save:                save();                break;            case R.id.button_cancel:                getActivity().getFragmentManager().popBackStack();//弹出 栈                break;        }    }    //数据提交到数据库    private void save() {        GamePlayer g = new GamePlayer();        //组件的输入内容添加 到数据库中        g.setId(gamePlayer.getId());        g.setPlayer(et_player.getText().toString());        g.setScore(Integer.parseInt(et_score.getText().toString()));        g.setLevel(Integer.parseInt(et_level.getText().toString()));        //调用 activity中的更新方法        updateFragmentListener.update(g);        getActivity().getFragmentManager().popBackStack(); //出栈    }    @Override    public void onDetach() {        super.onDetach();        updateFragmentListener = null;    }}

最后MainActivity（完成跟Fragment之间的交互及数据库方法）

mainActivity.xml(装Fragment)

<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:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".Main1229Activity">    <FrameLayout        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/main_layout"/></RelativeLayout>

MainActivity

public class Main1229Activity extends AppCompatActivity implements AddFragment.AddFragmentListener,        GamePlayFragment.GamePlayerFragmentListener,UpdateFragment.UpdateFragmentListener{    //操作数据库    private DatabaseAdapter dbAdapter;    //要交互的 fragment    private GamePlayFragment gamePlayerFragment; //显示数据界面    private UpdateFragment updateFragment; //更新数据界面    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main1229);        dbAdapter = new DatabaseAdapter(this);//实例化操作数据库类        //显示列表数据        showGamePlayerFragment();    }    /**     * 实例化菜单 布局     */    @Override    public boolean onCreateOptionsMenu(Menu menu) {        getMenuInflater().inflate(R.menu.menu_main1229, menu);        return true;    }    /**     * 当点击菜单项按钮时触发     */    @Override    public boolean onOptionsItemSelected(MenuItem item) {        int id = item.getItemId();        switch (id) {            case R.id.add://添加按钮的操作               AddFragment createGamePlayerFragment=AddFragment.newInstance();                createGamePlayerFragment.show(getFragmentManager(),null);                break;        }        return super.onOptionsItemSelected(item);    }    //添加    @Override    public void add(GamePlayer gamePlayer) {        dbAdapter.add(gamePlayer);        gamePlayerFragment.changeData();//添加后，重新加载数据    }    //显示列表    @Override    public void showGamePlayerFragment() {        //获取 显示数据列表的fragment对象        gamePlayerFragment = GamePlayFragment.newInstance();// 会调用:onCreateView方法        //开启事务        FragmentTransaction ft = getFragmentManager().beginTransaction();        //将 activity 中的布局文件 替换成 fragment        ft.replace(R.id.main_layout, gamePlayerFragment);        ft.addToBackStack(null);        ft.commit();    }    //显示更新fragment    @Override    public void showUpdateFragment(int id) {        updateFragment = UpdateFragment.newInstance(id);        FragmentTransaction ft = getFragmentManager().beginTransaction();        ft.replace(R.id.main_layout, updateFragment);        ft.addToBackStack(null);        ft.commit();    }    //删除    @Override    public void delete(int id) {        dbAdapter.delete(id);        gamePlayerFragment.changeData();//删除后 重新加载数据    }    //查找所有    @Override    public ArrayList<GamePlayer> findAll() {        return dbAdapter.findAll();    }    //查找一个    @Override    public GamePlayer findById(int id) {        return dbAdapter.findById(id);    }    //更新数据    @Override    public void update(GamePlayer gamePlayer) {        dbAdapter.update(gamePlayer);        gamePlayerFragment.changeData();//更新后 重新加载数据    }    /****************手机按键 监听事件*******************************/    @Override    public boolean onKeyDown(int keyCode, KeyEvent event) {        if (keyCode == KeyEvent.KEYCODE_BACK){            if(getFragmentManager().getBackStackEntryCount()==1){//当 栈中只是一个fragment时，就结束程序                finish();                return true;            }else {                getFragmentManager().popBackStack();                return true;            }        }        return super.onKeyDown(keyCode, event);    }}

六丶小总结

1.熟悉掌握了SQLite的基本用法

2.加强了Fragment与Activity的交互

3.由于刚入门开始借用了有很多小错误的代码，找BUG各种挣扎，拖到现在才完成对于本节的学习