Java 为什么我的循环只输出最后的结果？_Java_Android_Sqlite_Textview_Android Sqlite

Java 为什么我的循环只输出最后的结果？

java android sqlite

Java 为什么我的循环只输出最后的结果？,java,android,sqlite,textview,android-sqlite,Java,Android,Sqlite,Textview,Android Sqlite,我正在构建一个Android Studio应用程序，其中的数据可以添加到SQLite数据库中。当我想将数据输出到页面时，它只显示数据库中的最后一个结果（它覆盖）。如何防止这种情况发生并输出所有数据这是我的密码： public void viewAll() { Cursor res = myDb.getAllData(); if (res.getCount() == 0) { // show error System.out.println("No

我正在构建一个Android Studio应用程序，其中的数据可以添加到SQLite数据库中。当我想将数据输出到页面时，它只显示数据库中的最后一个结果（它覆盖）。如何防止这种情况发生并输出所有数据

这是我的密码：

public void viewAll() {
    Cursor res = myDb.getAllData();
    if (res.getCount() == 0) {
        // show error
        System.out.println("No Data Found");
        return;
    }

    while (res.moveToNext()) {
        System.out.println("Id: " + res.getString(0) + "\n");
        System.out.println("Title: " + res.getString(1) + "\n");
        System.out.println("Description: " + res.getString(2) + "\n");
        System.out.println("Location: " + res.getString(4) + "\n\n");
        TextView textViewID = (TextView) findViewById(R.id.textViewID);
        textViewID.setText("Id: " + res.getString(0) + "\n");
        TextView textViewName = (TextView) findViewById(R.id.textViewName);
        textViewName.setText("Name: " + res.getString(1) + "\n");
        TextView textViewDescription = (TextView) findViewById(R.id.textViewDescription);
        textViewDescription.setText("Description: " + res.getString(2) + "\n");
        TextView textViewLocation = (TextView) findViewById(R.id.textViewLocation);
        textViewLocation.setText("Location: " + res.getString(4) + "\n");
    }

    // show all the data

}

预期结果是数据库中的所有数据，但它只输出最后一个条目

编辑

MyActivity.java

package com.example.triptracker;
import android.content.Intent;
import android.database.Cursor;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

public class MomentsActivity extends AppCompatActivity {

private TextView mTextMessage;

private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
        = new BottomNavigationView.OnNavigationItemSelectedListener() {

    @Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.navigation_moments:
                Intent intent = new Intent(MomentsActivity.this, MomentsActivity.class);
                intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
                startActivity(intent);
                break;

            case R.id.navigation_addmoment:
                Intent intent2 = new Intent(MomentsActivity.this, AddMomentActivity.class);
                intent2.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
                startActivity(intent2);
                break;
        }
        return false;
    }
};

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    myDb = new DatabaseHelper(this);
    setContentView(R.layout.activity_moments);
    BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
    navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
    mList = this.findViewById(R.id.my_listview);
    manageListView();
}

DatabaseHelper myDb;
EditText editTitle, editDescription, editLocation;
Button btnAddData;
Button btnViewAll;
SimpleCursorAdapter mSCA; //Adapts/Handles the data for the listview
ListView mList;
Cursor mCsr;

int[] item_layout_ids_for_list = new int[]{
        R.id.textview_id,
        R.id.textview_name,
        R.id.textview_description,
        R.id.textview_location
};

String[] columns_to_list = new String[]{
        DatabaseHelper.COL_1,
        DatabaseHelper.COL_2,
        DatabaseHelper.COL_3,
        DatabaseHelper.COL_4
};

private void manageListView() {
    mCsr = myDb.getAllData();
    if (mSCA == null) {
        // Builds the Adapter for the List
        mSCA = new SimpleCursorAdapter(
                this,
                R.layout.mylistview_item, mCsr,
                columns_to_list,
                item_layout_ids_for_list,
                0
        );
        mList.setAdapter(mSCA); // Ties the Adapter to the ListView
    } else {
        mSCA.swapCursor(mCsr); // Refresh the List
    }
}

@Override
protected void onDestroy() {
    super.onDestroy();
    mCsr.close();
}

@Override
protected void onResume() {
    super.onResume();
    manageListView();
}

package com.example.triptracker;

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

public class DatabaseHelper extends SQLiteOpenHelper {

public static final String DATABASE_NAME = "triptracker.db";
public static final String TABLE_NAME = "trip_table";
public static final String COL_1 = "trip_id";
public static final String COL_2 = "trip_title";
public static final String COL_3 = "trip_description";
public static final String COL_4 = "trip_image";
public static final String COL_5 = "trip_location";


public DatabaseHelper(Context context) {
    super(context, DATABASE_NAME, null, 1);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("create table " + TABLE_NAME + " (" + COL_1 + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COL_2 + " TEXT, " + COL_3 + " TEXT, " + COL_4 + " TEXT, " + COL_5 + " TEXT)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("drop table if exists " + TABLE_NAME);
    onCreate(db);
}

// TODO: Add image functionality.

public boolean insertData(String title, String description, String location) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(COL_2, title);
    contentValues.put(COL_3, description);
    // contentValues.put(COL_4, image);
    contentValues.put(COL_5, location);
    long result = db.insert(TABLE_NAME, null, contentValues);
    if (result == -1)
        return false;
    else
        return true;

}

public Cursor getAllData() {
    SQLiteDatabase db = this.getWritableDatabase();
    Cursor res = db.rawQuery("select * from " + TABLE_NAME, null);
    return res;
}

}

DatabaseHelper.java

package com.example.triptracker;
import android.content.Intent;
import android.database.Cursor;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

public class MomentsActivity extends AppCompatActivity {

private TextView mTextMessage;

private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
        = new BottomNavigationView.OnNavigationItemSelectedListener() {

    @Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        switch (item.getItemId()) {
            case R.id.navigation_moments:
                Intent intent = new Intent(MomentsActivity.this, MomentsActivity.class);
                intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
                startActivity(intent);
                break;

            case R.id.navigation_addmoment:
                Intent intent2 = new Intent(MomentsActivity.this, AddMomentActivity.class);
                intent2.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
                startActivity(intent2);
                break;
        }
        return false;
    }
};

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    myDb = new DatabaseHelper(this);
    setContentView(R.layout.activity_moments);
    BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
    navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
    mList = this.findViewById(R.id.my_listview);
    manageListView();
}

DatabaseHelper myDb;
EditText editTitle, editDescription, editLocation;
Button btnAddData;
Button btnViewAll;
SimpleCursorAdapter mSCA; //Adapts/Handles the data for the listview
ListView mList;
Cursor mCsr;

int[] item_layout_ids_for_list = new int[]{
        R.id.textview_id,
        R.id.textview_name,
        R.id.textview_description,
        R.id.textview_location
};

String[] columns_to_list = new String[]{
        DatabaseHelper.COL_1,
        DatabaseHelper.COL_2,
        DatabaseHelper.COL_3,
        DatabaseHelper.COL_4
};

private void manageListView() {
    mCsr = myDb.getAllData();
    if (mSCA == null) {
        // Builds the Adapter for the List
        mSCA = new SimpleCursorAdapter(
                this,
                R.layout.mylistview_item, mCsr,
                columns_to_list,
                item_layout_ids_for_list,
                0
        );
        mList.setAdapter(mSCA); // Ties the Adapter to the ListView
    } else {
        mSCA.swapCursor(mCsr); // Refresh the List
    }
}

@Override
protected void onDestroy() {
    super.onDestroy();
    mCsr.close();
}

@Override
protected void onResume() {
    super.onResume();
    manageListView();
}

package com.example.triptracker;

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

public class DatabaseHelper extends SQLiteOpenHelper {

public static final String DATABASE_NAME = "triptracker.db";
public static final String TABLE_NAME = "trip_table";
public static final String COL_1 = "trip_id";
public static final String COL_2 = "trip_title";
public static final String COL_3 = "trip_description";
public static final String COL_4 = "trip_image";
public static final String COL_5 = "trip_location";


public DatabaseHelper(Context context) {
    super(context, DATABASE_NAME, null, 1);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL("create table " + TABLE_NAME + " (" + COL_1 + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COL_2 + " TEXT, " + COL_3 + " TEXT, " + COL_4 + " TEXT, " + COL_5 + " TEXT)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("drop table if exists " + TABLE_NAME);
    onCreate(db);
}

// TODO: Add image functionality.

public boolean insertData(String title, String description, String location) {
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(COL_2, title);
    contentValues.put(COL_3, description);
    // contentValues.put(COL_4, image);
    contentValues.put(COL_5, location);
    long result = db.insert(TABLE_NAME, null, contentValues);
    if (result == -1)
        return false;
    else
        return true;

}

public Cursor getAllData() {
    SQLiteDatabase db = this.getWritableDatabase();
    Cursor res = db.rawQuery("select * from " + TABLE_NAME, null);
    return res;
}

}

它正在输出这些错误：

2019-05-09 14:23:47.959 21253-21253/com.example.triptracker E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.triptracker, PID: 21253
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.triptracker/com.example.triptracker.MomentsActivity}: java.lang.IllegalArgumentException: column '_id' does not exist. Available columns: [trip_id, trip_title, trip_description, trip_image, trip_location]
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2913)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:193)
    at android.app.ActivityThread.main(ActivityThread.java:6669)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
 Caused by: java.lang.IllegalArgumentException: column '_id' does not exist. Available columns: [trip_id, trip_title, trip_description, trip_image, trip_location]
    at android.database.AbstractCursor.getColumnIndexOrThrow(AbstractCursor.java:340)
    at android.widget.CursorAdapter.init(CursorAdapter.java:180)
    at android.widget.CursorAdapter.<init>(CursorAdapter.java:157)
    at android.widget.ResourceCursorAdapter.<init>(ResourceCursorAdapter.java:96)
    at android.widget.SimpleCursorAdapter.<init>(SimpleCursorAdapter.java:104)
    at com.example.triptracker.MomentsActivity.manageListView(MomentsActivity.java:81)
    at com.example.triptracker.MomentsActivity.onCreate(MomentsActivity.java:52)
    at android.app.Activity.performCreate(Activity.java:7136)
    at android.app.Activity.performCreate(Activity.java:7127)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:193) 
    at android.app.ActivityThread.main(ActivityThread.java:6669) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 
2019-05-09 14:23:47.983 21253-21253/com.example.triptracker I/Process: Sending signal. PID: 21253 SIG: 9

2019-05-09 14:23:47.959 21253-21253/com.example.triptracker E/AndroidRuntime:致命异常：main
进程：com.example.triptracker，PID:21253
java.lang.RuntimeException:无法启动活动组件信息{com.example.triptracker/com.example.triptracker.MomentsActivity}:java.lang.IllegalArgumentException:列'\u id'不存在。可用列：[行程id、行程标题、行程描述、行程图像、行程位置]
位于android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2913）
位于android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:3048）
在android.app.servertransaction.LaunchActivityItem.execute（LaunchActivityItem.java:78）
在android.app.servertransaction.TransactionExecutor.executeCallbacks（TransactionExecutor.java:108）中
在android.app.servertransaction.TransactionExecutor.execute（TransactionExecutor.java:68）中
在android.app.ActivityThread$H.handleMessage（ActivityThread.java:1808）
位于android.os.Handler.dispatchMessage（Handler.java:106）
位于android.os.Looper.loop（Looper.java:193）
位于android.app.ActivityThread.main（ActivityThread.java:6669）
位于java.lang.reflect.Method.invoke（本机方法）
位于com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run（RuntimeInit.java:493）
位于com.android.internal.os.ZygoteInit.main（ZygoteInit.java:858）
原因：java.lang.IllegalArgumentException:列“\u id”不存在。可用列：[行程id、行程标题、行程描述、行程图像、行程位置]
位于android.database.AbstractCursor.getColumnIndexOrThrow（AbstractCursor.java:340）
位于android.widget.CursorAdapter.init（CursorAdapter.java:180）
位于android.widget.CursorAdapter.（CursorAdapter.java:157）
位于android.widget.ResourceCursorAdapter。（ResourceCursorAdapter.java:96）
位于android.widget.SimpleCursorAdapter。（SimpleCursorAdapter.java:104）
位于com.example.triptracker.MomentsActivity.manageListView（MomentsActivity.java:81）
在com.example.triptracker.MomentsActivity.onCreate（MomentsActivity.java:52）上
位于android.app.Activity.performCreate（Activity.java:7136）
位于android.app.Activity.performCreate（Activity.java:7127）
位于android.app.Instrumentation.callActivityOnCreate（Instrumentation.java:1271）
在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2893）上
位于android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:3048）
在android.app.servertransaction.LaunchActivityItem.execute（LaunchActivityItem.java:78）
在android.app.servertransaction.TransactionExecutor.executeCallbacks（TransactionExecutor.java:108）中
在android.app.servertransaction.TransactionExecutor.execute（TransactionExecutor.java:68）中
在android.app.ActivityThread$H.handleMessage（ActivityThread.java:1808）
位于android.os.Handler.dispatchMessage（Handler.java:106）
位于android.os.Looper.loop（Looper.java:193）
位于android.app.ActivityThread.main（ActivityThread.java:6669）
位于java.lang.reflect.Method.invoke（本机方法）
位于com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run（RuntimeInit.java:493）
位于com.android.internal.os.ZygoteInit.main（ZygoteInit.java:858）
2019-05-09 14:23:47.983 21253-21253/com.example.triptracker I/过程：发送信号。PID:21253信号：9

原因是，对于循环的每次迭代，您都将TextView的值设置为该迭代的值，因此您很可能只看到最后一行

您可以使用：-

public void viewAll() {
    Cursor res = myDb.getAllData();
    if (res.getCount() == 0) {
        // show error
        System.out.println("No Data Found");
        return;
    }

   TextView textViewID = (TextView) findViewById(R.id.textViewID);
   textViewID.setText("");
   TextView textViewName = (TextView) findViewById(R.id.textViewName);
   textViewName.setText("");
   TextView textViewDescription = (TextView) findViewById(R.id.textViewDescription);
   textViewDescription.setText("");
   TextView textViewLocation = (TextView) findViewById(R.id.textViewLocation);
   textViewLocation.setText("");


    while (res.moveToNext()) {
        System.out.println("Id: " + res.getString(0) + "\n");
        System.out.println("Title: " + res.getString(1) + "\n");
        System.out.println("Description: " + res.getString(2) + "\n");
        System.out.println("Location: " + res.getString(4) + "\n\n");
        textViewId.setText(textViewID.getText().toString()+res.getString(0) + "\n");
        textViewName.setText(textViewName.getText().toString()+"Name: " + res.getString(1) + "\n");
        textViewDescription.setText(textViewDescription.getText().toString() + "Description: " + res.getString(2) + "\n");
        textViewLocation.setText(textViewLocation.getText().toString() + "Location: " + res.getString(4) + "\n");
    }
}

或者更好 -循环中的字符串串联效率很低 -这也仅在第一行字符后追加一个新行字符

但是，您可能希望使用ListView或RecyclerView

附加-使用ListView 重要提示

本例使用了一个游标适配器，这使生活变得非常简单，但它们要求存在一个专门命名为\u id的列（id不起作用）。您可能必须更改表，以便将列命名为\u id（您可以使用常量BaseColumns.\u id，如下所示的DBHelper中使用的那样）。还有其他方法，例如在选择（查询）中创建一个_id列，例如从_表中选择rowid作为_id*

1在活动的布局中添加（替换id/name/description/location的文本视图）列表视图，确保您为其提供了一个id，例如：-

<ListView
    android:id="@+id/my_listview"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</ListView>

4添加以下int数组作为类变量：-

int[] item_layout_ids_for_list = new int[]{
        R.id.textview_id,
        R.id.textview_name,
        R.id.textview_description,
        R.id.textview_location
};

请注意，这些是布局mylistview\u item.xml中TextView的id，适配器将使用这些id将数据从列映射到TextView

5类似地为要从中检索数据的列名添加字符串数组；但请注意，您将/可能必须更改列名（以下使用数据库帮助器中定义的常量（建议定义此类常量，并始终使用常量，而不是硬编码名称）），例如：-
6将以下方法添加到活动中：-

private void manageListView() { mCsr = myDb.getAllData(); if (mSCA == null) { // Builds the Adapter for the List mSCA = new SimpleCursorAdapter( this, R.layout.mylistview_item, mCsr, columns_to_list, item_layout_ids_for_list, 0 ); mList.setAdapter(mSCA); // Ties the Adapter to the ListView } else { mSCA.swapCursor(mCsr); // Refresh the List } }

正如方法所说，它管理ListView。它将数据从数据库获取到一个游标中，构造（实例化）SimpleCursorAdapter（如果尚未实例化），然后将适配器绑定到ListView。如果适配器已实例化，它会告诉适配器存在
String[] columns_to_list = new String[]{ DBHelper.COL_MYTABLE_ID, DBHelper.COl_MYTABLE_NAME, DBHelper.COL_MYTABLE_DESCRIPTION, DBHelper.COl_MYTABLE_LOCATION };

private void manageListView() { mCsr = myDb.getAllData(); if (mSCA == null) { // Builds the Adapter for the List mSCA = new SimpleCursorAdapter( this, R.layout.mylistview_item, mCsr, columns_to_list, item_layout_ids_for_list, 0 ); mList.setAdapter(mSCA); // Ties the Adapter to the ListView } else { mSCA.swapCursor(mCsr); // Refresh the List } }

mList = this.findViewById(R.id.my_listview); myDb = new DBHelper(this); //<<<<<<<<<< SHOULD ALREADY HAVE SOMETHING LIKE THIS LEAVE AS IT IS manageListView();

@Override protected void onDestroy() { super.onDestroy(); mCsr.close(); } @Override protected void onResume() { super.onResume(); manageListView(); }

public class MainActivity extends AppCompatActivity { DBHelper myDb; SimpleCursorAdapter mSCA; //Adapts/Handles the data for the listview ListView mList; Cursor mCsr; String[] columns_to_list = new String[]{ DBHelper.COL_MYTABLE_ID, DBHelper.COl_MYTABLE_NAME, DBHelper.COL_MYTABLE_DESCRIPTION, DBHelper.COl_MYTABLE_LOCATION }; int[] item_layout_ids_for_list = new int[]{ R.id.textview_id, R.id.textview_name, R.id.textview_description, R.id.textview_location }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mList = this.findViewById(R.id.my_listview); myDb = new DBHelper(this); forTestingAddSomeData(); manageListView(); } private void manageListView() { mCsr = myDb.getAllData(); if (mSCA == null) { // Builds the Adapter for the List mSCA = new SimpleCursorAdapter( this, R.layout.mylistview_item, mCsr, columns_to_list, item_layout_ids_for_list, 0 ); mList.setAdapter(mSCA); // Ties the Adapter to the ListView } else { mSCA.swapCursor(mCsr); // Refresh the List } } private void forTestingAddSomeData() { if(DatabaseUtils.queryNumEntries(myDb.getWritableDatabase(),DBHelper.TABLE_MYTABLE) < 1) { myDb.add("Test001","This is a test","Home"); myDb.add("Test002","For Testing","Garage"); myDb.add("Test003","Test using this","Loft"); myDb.add("Test004","Yet again for testing","Cupboard"); } } @Override protected void onDestroy() { super.onDestroy(); mCsr.close(); } @Override protected void onResume() { super.onResume(); manageListView(); } }

public class DBHelper extends SQLiteOpenHelper { public static final String DBNAME = "mydb"; public static final int DBVERSION = 1; public static final String TABLE_MYTABLE = "mytable"; public static final String COL_MYTABLE_ID = BaseColumns._ID; public static final String COl_MYTABLE_NAME = "name"; public static final String COL_MYTABLE_DESCRIPTION = "description"; public static final String COl_MYTABLE_LOCATION = "location"; SQLiteDatabase mDB; public DBHelper(Context context) { super(context, DBNAME, null, DBVERSION); mDB = this.getWritableDatabase(); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE IF NOT EXISTS " + TABLE_MYTABLE + "(" + COL_MYTABLE_ID + " INTEGER PRIMARY KEY," + COl_MYTABLE_NAME + " TEXT, " + COL_MYTABLE_DESCRIPTION + " TEXT, " + COl_MYTABLE_LOCATION + " TEXT" + ")" ); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } public long add(String name, String description, String location) { ContentValues cv = new ContentValues(); cv.put(COl_MYTABLE_NAME,name); cv.put(COL_MYTABLE_DESCRIPTION,description); cv.put(COl_MYTABLE_LOCATION,location); return mDB.insert(TABLE_MYTABLE,null,cv); } public Cursor getAllData() { return mDB.query(TABLE_MYTABLE,null,null,null,null,null,null); } }