簡單的Listview顯示，new_adapter報錯，找不到原因

package com.baidu.listview;

import android.app.Activity;

import android.content.Context;

import android.graphics.Color;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.Button;

import android.widget.LinearLayout;

import android.widget.ListView;

import android.widget.TextView;

import android.widget.Toast;

import java.util.ArrayList;

import java.util.List;



public class MainActivity extends Activity implements View.OnClickListener {

    private DatabaseHelper iDatabaseHelper;

    private Button Btn_CreateDB,Btn_ShowListView;

    private DatabaseDAO iDatabaseDAO;

    private List<DataGetSet> iList;

    private LinearLayout LayoutRoot;

    private ListView iListView;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        iDatabaseHelper = new DatabaseHelper(this);

        Btn_CreateDB = (Button)findViewById(R.id.Btn_SetDatabase);

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

        LayoutRoot = (LinearLayout)findViewById(R.id.Layout_ShowListViewSpeace);

        iListView = (ListView)findViewById(R.id.Control_ListView);

        iListView.setAdapter(new MyAdapter());

        Btn_CreateDB.setOnClickListener(this);

        Btn_ShowListView.setOnClickListener(this);



    }



    @Override

    public void onClick(View v) {

        switch(v.getId()){

            case R.id.Btn_SetDatabase: //創建資料庫并初始化資料

                try{

                    iDatabaseHelper.getWritableDatabase();

                }catch (Exception e){

                    ToastMessage(this,"例外！原因：\n"+e.getMessage().toString(),0);

                }finally {

                    ToastMessage(this,"資料庫創建成功!",0);

                    iDatabaseDAO = new DatabaseDAO(MainActivity.this);

                    long getLongNumber = iDatabaseDAO.DataAddToBase();

                    if(getLongNumber!=0){

                        ToastMessage(this,"資料初始化成功！!",0);

                    }else{

                        ToastMessage(this,"資料初始化失敗，請稍后嘗試！!",0);

                    }

                }

                break;

            case R.id.Btn_ShowListView: //顯示ListView資料



                break;

        }

    }

    private class MyAdapter extends BaseAdapter{



        @Override

        public int getCount() {

            return iList.size();

        }



        @Override

        public Object getItem(int position) {

            return null;

        }



        @Override

        public long getItemId(int position) {

            return 0;

        }



        @Override

        public View getView(int position, View convertView, ViewGroup parent) {

            TextView TextControl = new TextView(getApplicationContext());

            TextControl.setTextSize(20);

            TextControl.setTextColor(Color.BLACK);

            //DataGetSet iDataGetSet = iList.get(position).ID;

            int id = iList.get(position).ID;

            String name = iList.get(position).User_Name;

            String number = iList.get(position).Phone_Number;

            //TextControl.setText(iDataGetSet.toString());

            TextControl.setText("ID:"+id+"\t\t"+number+"\t\t"+number);

            //LayoutRoot.addView(TextControl);



            return TextControl;

       }

    }

    private void ToastMessage (Context context, String msg,int serial){

        Toast.makeText(context,msg,serial).show();

    }

}

package com.baidu.listview;



import android.content.ContentValues;

import android.content.Context;

import android.database.Cursor;

import android.database.sqlite.SQLiteDatabase;



import java.util.ArrayList;

import java.util.List;



public class DatabaseDAO {

    private DatabaseHelper iDatabaseHelper;

    public DatabaseDAO (Context context){

        iDatabaseHelper = new DatabaseHelper(context);

    }

    public long DataAddToBase(){

        long getLongState = 0;

        SQLiteDatabase db = iDatabaseHelper.getWritableDatabase();

        ContentValues iValues = new ContentValues();

        for(int i=0;i<50;i++){

            iValues.put("user_name","王網速"+i);

            iValues.put("phone_number","13455433"+i);

           getLongState = db.insert("AppTable",null,iValues);

        }

        db.close();

        return getLongState;

    }

    public List<DataGetSet> FindDataAll(){

        List<DataGetSet> iDatabase = new ArrayList<DataGetSet>();

        SQLiteDatabase db = iDatabaseHelper.getReadableDatabase();

        Cursor iCursor = db.query("AppTable",new String[]{"id","user_name","phone_number"},null,null,null,null,null);

        while(iCursor.moveToNext()){

            int ID_get = iCursor.getInt(iCursor.getColumnIndex("id"));

            String UserName_Get = iCursor.getString(iCursor.getColumnIndex("user_name"));

            String Phone_Number_Get = iCursor.getString(iCursor.getColumnIndex("phone_number"));

            DataGetSet iDataGetSet = new DataGetSet(ID_get,UserName_Get,Phone_Number_Get);

            iDatabase.add(iDataGetSet);

        }

        return iDatabase;

    }

}

package com.baidu.listview;



import android.content.Context;

import android.database.sqlite.SQLiteDatabase;

import android.database.sqlite.SQLiteOpenHelper;



public class DatabaseHelper extends SQLiteOpenHelper {

    public DatabaseHelper(Context context) {

        super(context, "apple.db", null, 1);

    }



    @Override

    public void onCreate(SQLiteDatabase db) {

        db.execSQL("create table AppTable(id integer primary key autoincrement,user_name varchar(20),phone_number varchar(20))");

    }



    @Override

    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {



    }

}

package com.baidu.listview;



public class DataGetSet {





    public int getID() {

        return ID;

    }



    public void setID(int ID) {

        this.ID = ID;

    }



    public String getUser_Name() {

        return User_Name;

    }



    public void setUser_Name(String user_Name) {

        User_Name = user_Name;

    }



    public String getPhone_Number() {

        return Phone_Number;

    }



    public void setPhone_Number(String phone_Number) {

        Phone_Number = phone_Number;

    }



    public DataGetSet(int ID, String user_Name, String phone_Number) {

        this.ID = ID;

        User_Name = user_Name;

        Phone_Number = phone_Number;

    }



    public DataGetSet() {

    }



    int ID;

    String User_Name;

    String Phone_Number;

}

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

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

    xmlns:tools="http://schemas.android.com/tools"

    android:id="@+id/Layout_Root"

    android:layout_width="match_parent"

    android:layout_height="match_parent">



    <LinearLayout

        android:id="@+id/Layout_ShowListViewSpeace"

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:layout_above="@+id/Layout_Meum"

        android:background="#D0ECF0"

        android:orientation="vertical"

        >

        <ListView

            android:id="@+id/Control_ListView"

            android:layout_width="match_parent"

            android:layout_height="wrap_content"/>



    </LinearLayout>



    <LinearLayout

        android:id="@+id/Layout_Meum"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_alignParentBottom="true"

        android:background="#A3D8E2"

        android:orientation="horizontal">



        <Button

            android:id="@+id/Btn_SetDatabase"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:text="@string/setData" />



        <Button

            android:id="@+id/Btn_ShowListView"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:textAllCaps="false"

            android:text="@string/showListView" />

    </LinearLayout>

</RelativeLayout>

<resources>

    <string name="app_name">ListView</string>

    <string name="setData">初始化資料庫</string>

    <string name="showListView">顯示ListView</string>

</resources>

05-06 10:59:04.138 32069-32069/? E/dalvikvm: Failed to symlink /storage/internalsd to /storage/emulated/legacy: File exists

05-06 10:59:04.408 32069-32069/com.baidu.listview E/AndroidRuntime: FATAL EXCEPTION: main

    Process: com.baidu.listview, PID: 32069

    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.baidu.listview/com.baidu.listview.MainActivity}: java.lang.NullPointerException

        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2288)

        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2337)

        at android.app.ActivityThread.access$800(ActivityThread.java:151)

        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1243)

        at android.os.Handler.dispatchMessage(Handler.java:102)

        at android.os.Looper.loop(Looper.java:159)

        at android.app.ActivityThread.main(ActivityThread.java:5377)

        at java.lang.reflect.Method.invokeNative(Native Method)

        at java.lang.reflect.Method.invoke(Method.java:515)

        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:976)

        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:792)

        at dalvik.system.NativeStart.main(Native Method)

     C

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