我实际上很困惑，而不是寻找任何新的东西来添加或纠正它让我困惑，现在我不知道要添加什么也不正确
我想从sqlite数据库中检索数据，点击按钮SEARCH TRIP然后我希望它显示在列表视图中，通过该列表视图我也可以点击其中一个列表视图并单击它以指示我显示另一个页面信息，但我仍然怀疑
在我的logcat中，运行时没有错误，当我点击按钮SEARCH TRIP没有任何反应没有错误我有这些类：DATABASEHELPER，LISTVIEWCURSORADAPTERACTIVITY，TRIPSDBADAPTER
按钮位于片段中，因为当我指定其中一个类（如LISTVIEWCURSORADAPTERACTIVITY或TRIPSDBADAPTER）时，当我在方法上实现View.onclicklistener时，其中一个按钮位于片段上显示错误我应该在哪里放置按钮的连接
如果可能的话，有人可以帮我解决一下我做错的代码吗？
DatabaseHelper.java
import android.content.Contect;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import java.util.ArrayList;
import java.util.List;
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "stallion_db";
public static final String TABLE_NAME = "one-way";
public static final String COL_1 = "depart from";
public static final String COL_2 = "arrive_to";
public static final String COL_3 = "report_time";
public static final String COL_4 = "depart_on";
public static final String COL_5 = "departure time";
public static final String COL_6 = "price";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "" + " (NO INTEGER PRIMARY KEY AUTOINCREMENT," +
" depart_from TEXT, arrive_to TEXT, report_time VARCHAR, depart_on DATE, departure_time VARCHAR," +
" price INTEGER); ");
db.execSQL("INSERT INTO oneway values (1, mombasa, nairobi, 10:30AM, 25-12-2015, 11:00AM, 900)");
db.execSQL("SELECT FROM oneway WHERE depart_from = mombasa and arrive_to = nairobi");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Getting All Contacts
public List<ConstructorOneWay> getAlltrips() {
List<ConstructorOneWay> tripList = new ArrayList<ConstructorOneWay>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
ConstructorOneWay trip = new ConstructorOneWay();
trip.setID(Integer.parseInt(cursor.getString(0)));
trip.setDepart(cursor.getString(1));
trip.setArrive(cursor.getString(2));
trip.setReport(cursor.getString(3));
trip.setdeparting(cursor.getString(4));
trip.setprice(Integer.parseInt(cursor.getString(5)));
// Adding trips to list
tripList.add(trip);
} while (cursor.moveToNext());
}
// return contact list
return tripList;
}
}
ListViewCursorAdapterActivity.java
import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
public class ListViewCursorAdaptorActivity extends Activity {
private TripsdbAdapter dbHelper;
private SimpleCursorAdapter dataAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.trip_listview);
dbHelper = new TripsdbAdapter(this);
dbHelper.open();
//Generate ListView from SQLite Database
displayListView();
}
private void displayListView() {
Cursor cursor = dbHelper.fetchallTrips();
// The desired columns to be bound
String[] columns = new String[] {
TripsdbAdapter.Depart_from,
TripsdbAdapter.Arrive_to,
TripsdbAdapter.Depart_on,
TripsdbAdapter.Departure_time,
TripsdbAdapter.Price,
};
// the XML defined views which the data will be bound to
int[] to = new int[] {
R.id.tv1,
R.id.tv2,
R.id.tv3,
R.id.tv4,
R.id.tv5,
};
// create the adapter using the cursor pointing to the desired data
//as well as the layout information
dataAdapter = new SimpleCursorAdapter(
this, R.layout.display_one_way_trip,
cursor,
columns,
to,
0);
ListView listView = (ListView) findViewById(R.id.listView1);
// Assign adapter to ListView
listView.setAdapter(dataAdapter);
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> listView, View view,
int position, long id) {
// Get the cursor, positioned to the corresponding row in the result set
Cursor cursor = (Cursor) listView.getItemAtPosition(position);
}
}); }}
TripsdbAdapter.java
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
public class TripsdbAdapter {
//FOR DISPLAYING AFTER SEARCH
public static final String ID = "id";
public static final String Depart_from = "Depart from";
public static final String Arrive_to = "Arrive to";
public static final String Depart_on = "Depart on";
public static final String Departure_time = "Departure time";
public static final String Price = "Price";
private static final String TAG = "TripsdbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
private static final String DATABASE_NAME = "stallion_db";
private static final String SQLITE_TABLE = "oneway";
private static final int DATABASE_VERSION = 1;
private Context mCtx;
public TripsdbAdapter(Context mContext) {
this.mCtx = mContext;
}
public void close() {
if (mDbHelper != null) {
mDbHelper.close();
}
}
public Cursor fetchCountriesByName(String inputText) throws SQLException {
Log.w(TAG, inputText);
Cursor mCursor = null;
if (inputText == null || inputText.length () == 0) {
mCursor = mDb.query(SQLITE_TABLE, new String[] {Depart_from,
Arrive_to, Depart_on, Departure_time, Price},
null, null, null, null, null);
}
else {
mCursor = mDb.query(true, SQLITE_TABLE, new String[] {Depart_from,
Arrive_to, Depart_on, Departure_time, Price},
Depart_from + " like '%" + inputText + "%'", null,
null, null, null, null);
}
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public Cursor fetchallTrips() {
Cursor mCursor = mDb.query(SQLITE_TABLE, new String[] {Depart_from,
Arrive_to, Depart_on, Departure_time, Price},
null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public void open() {
} }
logcat的：
答案 0 :(得分：0)
主要活动
public class MainActivity extends AppCompatActivity {
private TripsdbAdapter dbHelper;
private SimpleCursorAdapter dataAdapter;
private Button btnGetList;
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dbHelper = new TripsdbAdapter(this);
dbHelper.open();
listView = (ListView) findViewById(R.id.listView1);
btnGetList = (Button) findViewById(R.id.btnGetList);
btnGetList.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
displayListView();
}
});
}
private void displayListView() {
Cursor cursor = dbHelper.fetchallTrips();
// The desired columns to be bound
String[] columns = new String[] {TripsdbAdapter.ID ,TripsdbAdapter.Depart_from, TripsdbAdapter.Arrive_to, TripsdbAdapter.Depart_on, TripsdbAdapter.Departure_time, TripsdbAdapter.Price, };
// the XML defined views which the data will be bound to
int[] to = new int[] { R.id.tv1, R.id.tv2, R.id.tv3, R.id.tv4, R.id.tv5,R.id.tv6
};
// create the adapter using the cursor pointing to the desired data
// as well as the layout information
dataAdapter = new SimpleCursorAdapter(this, R.layout.display_one_way_trip, cursor, columns, to, 0);
// Assign adapter to ListView
listView.setAdapter(dataAdapter);
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> listView, View view, int position, long id) {
// Get the cursor, positioned to the corresponding row in the
// result set
Cursor cursor = (Cursor) listView.getItemAtPosition(position);
}
});
}
public class TripsdbAdapter {
// FOR DISPLAYING AFTER SEARCH
public static final String ID = "_id";
public static final String Depart_from = "depart_from";
public static final String Arrive_to = "arrive_to";
public static final String Depart_on = "depart_on";
public static final String Departure_time = "departure_time";
public static final String Price = "price";
private static final String TAG = "TripsdbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
private static final String DATABASE_NAME = "stallion_db";
private static final String SQLITE_TABLE = "oneway";
private static final int DATABASE_VERSION = 1;
private Context mCtx;
public TripsdbAdapter(Context mContext) {
this.mCtx = mContext;
mDbHelper = new DatabaseHelper(mContext);
}
public void close() {
if (mDbHelper != null) {
mDbHelper.close();
}
}
public Cursor fetchCountriesByName(String inputText) throws SQLException {
Log.w(TAG, inputText);
Cursor mCursor = null;
if (inputText == null || inputText.length() == 0) {
mCursor = mDb.query(SQLITE_TABLE, new String[] { Depart_from, Arrive_to, Depart_on, Departure_time, Price }, null, null, null, null, null);
} else {
mCursor = mDb.query(true, SQLITE_TABLE, new String[] { Depart_from, Arrive_to, Depart_on, Departure_time, Price }, Depart_from + " like '%" + inputText + "%'",
null, null, null, null, null);
}
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public Cursor fetchallTrips() {
Cursor mCursor = mDb.query(SQLITE_TABLE, new String[] {ID,Depart_from, Arrive_to, Depart_on, Departure_time, Price }, null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public void open() {
mDb = mDbHelper.getReadableDatabase();
}
}
}
DatabaseHelper
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "stallion_db";
public static final String TABLE_NAME = "oneway";
public static final String COL_1 = "depart_from";
public static final String COL_2 = "arrive_to";
public static final String COL_3 = "report_time";
public static final String COL_4 = "depart_on";
public static final String COL_5 = "departure_time";
public static final String COL_6 = "price";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "" + " (NO INTEGER PRIMARY KEY AUTOINCREMENT,"
+ " depart_from TEXT, arrive_to TEXT, report_time VARCHAR, depart_on DATE, departure_time VARCHAR," + " price INTEGER); ");
db.execSQL("INSERT INTO oneway values (1, 'mombasa', 'nairobi', '10:30AM', '25-12-2015', '11:00AM', 900)");
db.execSQL("INSERT INTO oneway values (2, 'abcd', 'nairobi', '10:30AM', '26-12-2015', '10:00AM', 800)");
db.execSQL("INSERT INTO oneway values (3, 'pqrs', 'nairobi', '10:30AM', '27-12-2015', '09:00AM', 700)");
// db.execSQL("SELECT FROM oneway WHERE depart_from = mombasa and arrive_to = nairobi");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Getting All Contacts
public List<ConstructorOneWay> getAlltrips() {
List<ConstructorOneWay> tripList = new ArrayList<ConstructorOneWay>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
ConstructorOneWay trip = new ConstructorOneWay();
trip.setID(Integer.parseInt(cursor.getString(0)));
trip.setDepart(cursor.getString(1));
trip.setArrive(cursor.getString(2));
trip.setReport(cursor.getString(3));
trip.setDeparting(cursor.getString(4));
trip.setPrice(Integer.parseInt(cursor.getString(5)));
// Adding trips to list
tripList.add(trip);
} while (cursor.moveToNext());
}
// return contact list
return tripList;
}
}
activity_main.xml中
<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" >
<Button
android:id="@+id/btnGetList"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Get All" />
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/btnGetList" >
</ListView>
</RelativeLayout>