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应用程序没有编码错误，但它在启动时崩溃。在 LogCat 中，我看到错误没有找到列，但我不知道问题出在哪里。我做了很多研究，但到目前为止还没有成功。这是我的课程的源代码：

MainActivity 类：

public class MainActivity extends ListActivity {

private StudentOperations studentDBoperation;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    studentDBoperation = new StudentOperations(this);
    studentDBoperation.open();

    List values = studentDBoperation.getAllStudents();

    // Use the SimpleCursorAdapter to show the
    // elements in a ListView
    ArrayAdapter adapter = new ArrayAdapter(this,
            android.R.layout.simple_list_item_1, values);
    setListAdapter(adapter);
}

public void addUser(View view) {

    ArrayAdapter adapter = (ArrayAdapter) getListAdapter();

    EditText text = (EditText) findViewById(R.id.editText1);
    EditText text1 = (EditText) findViewById(R.id.editText2);
    Student stud = studentDBoperation.addStudent(text.getText().toString(),text1.getText().toString());

    adapter.add(stud);

}

public void deleteFirstUser(View view) {

    ArrayAdapter adapter = (ArrayAdapter) getListAdapter();
    Student stud = null;

    if (getListAdapter().getCount() > 0) {
        stud = (Student) getListAdapter().getItem(0);
        studentDBoperation.deleteStudent(stud);
        adapter.remove(stud);
    }

}

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

@Override
protected void onPause() {
    studentDBoperation.close();
    super.onPause();
}

}

学生班级：

public class Student {

private int id;
private String name;
private String password;

public long getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getName() {
    return this.name;
}

public void setName(String name) {
    this.name = name;
}

@Override
public String toString() {
    return name;
}

public String getPassword() {
    return this.password;
}

public void setPassword(String password) {
    this.password = password;
}

}

学生操作课：

public class StudentOperations {

// Database fields
private DataBaseWrapper dbHelper;
private String[] STUDENT_TABLE_COLUMNS = { DataBaseWrapper.STUDENT_ID, DataBaseWrapper.STUDENT_NAME, DataBaseWrapper.STUDENT_PASSWORD };
private SQLiteDatabase database;

public StudentOperations(Context context) {
    dbHelper = new DataBaseWrapper(context);
}

public void open() throws SQLException {
    database = dbHelper.getWritableDatabase();
}

public void close() {
    dbHelper.close();
}

public Student addStudent(String name,String password) {

    ContentValues values = new ContentValues();

    values.put(DataBaseWrapper.STUDENT_NAME, name);
    values.put(DataBaseWrapper.STUDENT_PASSWORD, password);

    long studId = database.insert(DataBaseWrapper.STUDENTS, null, values);

    // now that the student is created return it ...
    Cursor cursor = database.query(DataBaseWrapper.STUDENTS,
            STUDENT_TABLE_COLUMNS, DataBaseWrapper.STUDENT_ID + " = "
                    + studId, null, null, null, null);

    cursor.moveToFirst();

    Student newComment = parseStudent(cursor);
    cursor.close();
    return newComment;
}

public void deleteStudent(Student comment) {
    long id = comment.getId();
    System.out.println("Comment deleted with id: " + id);
    database.delete(DataBaseWrapper.STUDENTS, DataBaseWrapper.STUDENT_ID
            + " = " + id, null);
}

public List getAllStudents() {
    List students = new ArrayList();

    Cursor cursor = database.query(DataBaseWrapper.STUDENTS,
            STUDENT_TABLE_COLUMNS, null, null, null, null, null);

    cursor.moveToFirst();
    while (!cursor.isAfterLast()) {
        Student student = parseStudent(cursor);
        students.add(student);
        cursor.moveToNext();
    }

    cursor.close();
    return students;
}

private Student parseStudent(Cursor cursor) {
    Student student = new Student();
    student.setId((cursor.getInt(0)));
    student.setName(cursor.getString(1));
    return student;
}

}

DataBaseWrapper 类：

public class DataBaseWrapper extends SQLiteOpenHelper {

public static final String STUDENTS = "Students";
public static final String STUDENT_ID = "_id";
public static final String STUDENT_NAME = "name";
public static final String STUDENT_PASSWORD = "password";

private static final String DATABASE_NAME = "Students.db";
private static final int DATABASE_VERSION = 1;

// creation SQLite statement
private static final String DATABASE_CREATE = "create table " + STUDENTS
        + "(" + STUDENT_ID + " integer primary key autoincrement, " + STUDENT_NAME + " text not null " + STUDENT_PASSWORD + " text not null ); ";

public DataBaseWrapper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
    db.execSQL(DATABASE_CREATE);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // you should do some logging in here
    // ..

    db.execSQL("DROP TABLE IF EXISTS " + STUDENTS);
    onCreate(db);
}

}

LogCat 错误：

11-05 21:51:02.430：D/AbsListView(26729)：获取 MotionRecognitionManager 11-05 21:51:02.470：E/SQLiteLog(26729)：(1) 没有这样的列：名称 11-05 21:51:02.470 ：D / AndroidRuntime（26729）：关闭VM 11-05 21：51：02.470：W / dalvikvm（26729）：threadid = 1：线程退出但未捕获异常（组= 0x410762a0）11-05 21：51：02.480： E/AndroidRuntime(26729): 致命异常: main 11-05 21:51:02.480: E/AndroidRuntime(26729): java.lang.RuntimeException: 无法启动活动 ComponentInfo{com.example.sqlite/com.example.sqlite .MainActivity}：android.database.sqlite.SQLiteException：没有这样的列：名称（代码1）：，编译时：SELECT _id，名称，密码来自学生11-05 21：51：02.480：E / AndroidRuntime（26729）：在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app。ActivityThread.handleLaunchActivity(ActivityThread.java:2125) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.access$600(ActivityThread.java:140) 11-05 21:51:02.480 : E/AndroidRuntime(26729): 在 android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.os.Handler.dispatchMessage( Handler.java:99) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.os.Looper.loop(Looper.java:137) 11-05 21:51:02.480: E/AndroidRuntime( 26729): 在 android.app.ActivityThread.main(ActivityThread.java:4898) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 java.lang.reflect.Method.invokeNative(Native Method) 11- 05 21:51:02.480: E/AndroidRuntime(26729): at java.lang.reflect.Method.invoke(Method.java:511) 11-05 21:51:02.480: E/AndroidRuntime(26729): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006) 11-05 21:51:02.480: E/AndroidRuntime(26729): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java :773) 11-05 21:51:02.480: E/AndroidRuntime(26729): at dalvik.system.NativeStart.main(Native Method) 11-05 21:51:02.480: E/AndroidRuntime(26729): 原因： android.database.sqlite.SQLiteException: no such column: name (code 1): , while compile: SELECT _id, name, password FROM Students 11-05 21:51:02.480: E/AndroidRuntime(26729): at android.database .sqlite.SQLiteConnection.nativePrepareStatement(Native Method) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:1012) 11-05 21:51: 02.480：E/AndroidRuntime(26729)：在 android.database.sqlite.SQLiteConnection。准备（SQLiteConnection.java:623）11-05 21:51:02.480：E/AndroidRuntime（26729）：在 android.database.sqlite.SQLiteSession.prepare（SQLiteSession.java:588）11-05 21:51:02.480： E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteProgram.(SQLiteProgram.java:58) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteQuery.(SQLiteQuery .java:37) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:44) 11-05 21:51:02.480: E/AndroidRuntime (26729): 在 android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase. java:1161) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database。sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1032) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1200) 11-05 21: 51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.StudentOperations.getAllStudents(StudentOperations.java:62) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite .MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity.java:5206) 11-05 21:51:02.480 : E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread. java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多查询（SQLiteDatabase.java:1032）11-05 21:51:02.480：E/AndroidRuntime（26729）：在 android.database.sqlite.SQLiteDatabase.query（SQLiteDatabase.java:1200）11-05 21:51:02.480： E/AndroidRuntime(26729): 在 com.example.sqlite.StudentOperations.getAllStudents(StudentOperations.java:62) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate (MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity.java:5206) 11-05 21:51:02.480: E/AndroidRuntime (26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多查询（SQLiteDatabase.java:1032）11-05 21:51:02.480：E/AndroidRuntime（26729）：在 android.database.sqlite.SQLiteDatabase.query（SQLiteDatabase.java:1200）11-05 21:51:02.480： E/AndroidRuntime(26729): 在 com.example.sqlite.StudentOperations.getAllStudents(StudentOperations.java:62) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate (MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity.java:5206) 11-05 21:51:02.480: E/AndroidRuntime (26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1200) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.StudentOperations .getAllStudents(StudentOperations.java:62) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480 : E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity.java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation. java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729) : ... 11 更多480: E/AndroidRuntime(26729): 在 android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1200) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.StudentOperations .getAllStudents(StudentOperations.java:62) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480 : E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity.java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation. java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729) : ... 11 更多查询（SQLiteDatabase.java:1200）11-05 21:51:02.480：E/AndroidRuntime（26729）：在 com.example.sqlite.StudentOperations.getAllStudents（StudentOperations.java:62）11-05 21:51:02.480： E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity .java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729 ): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多查询（SQLiteDatabase.java:1200）11-05 21:51:02.480：E/AndroidRuntime（26729）：在 com.example.sqlite.StudentOperations.getAllStudents（StudentOperations.java:62）11-05 21:51:02.480： E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity .java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729 ): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity .java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729 ): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多E/AndroidRuntime(26729): 在 com.example.sqlite.MainActivity.onCreate(MainActivity.java:23) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Activity.performCreate(Activity .java:5206) 11-05 21:51:02.480: E/AndroidRuntime(26729): 在 android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083) 11-05 21:51:02.480: E/AndroidRuntime(26729 ): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多E/AndroidRuntime(26729): 在 android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064) 11-05 21:51:02.480: E/AndroidRuntime(26729): ... 11 更多

4

3 回答 3

1

在 DATABASE_CREATE 语句中，名称和密码列定义之间的逗号缺失。

于 2013-11-05T21:21:22.080 回答
1

当我在我的 Databasehandler 文件（在您的情况下为 DataBaseWrapper）中更改（即附加一列）时，我遇到了类似的错误。从设备上卸载我的应用程序然后再次安装后，我发现它已解决。看它。

于 2014-04-22T07:28:18.617 回答
0

您需要在 create 语句中添加逗号并删除分号。尝试改变：

// creation SQLite statement
private static final String DATABASE_CREATE = "create table " + STUDENTS
    + "(" + STUDENT_ID + " integer primary key autoincrement, " + STUDENT_NAME + " text not null " + STUDENT_PASSWORD + " text not null ); ";

至：

// creation SQLite statement
private static final String DATABASE_CREATE = "create table " + STUDENTS
    + "(" + STUDENT_ID + " integer primary key autoincrement, " + STUDENT_NAME + " text not null, " + STUDENT_PASSWORD + " text not null )";
于 2015-06-06T19:04:47.347 回答