我正在尝试将值插入 SQLite Android 应用程序数据库。
我正在编写以下代码:
public class DataBaseAdapter extends SQLiteOpenHelper
{
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "AlarmSystem";
// Alarm table name
private static final String TABLE_NAME = "Alarms";
//AlarmTable Columns names
private static final String KEY_ALARM_ID = "Id";
private static final String KEY_DESC = "Description";
private static final String KEY_REPEAT_DAY = "RepeatDay";
private static final String KEY_REPEAT_TYPE = "REPEAT_TYPE";
private static final String KEY_CALENDAR = "Calendar";
private static final String KEY_APP = "Device";
private static final String KEY_ACTIVE = "Active";
//creating database
public DataBaseAdapter(Context con)
{
super(con, DATABASE_NAME, null, DATABASE_VERSION);
}
//creating table
@Override
public void onCreate(SQLiteDatabase db)
{
String CREATE_TABLE = "Create Table "+TABLE_NAME+"("
+KEY_ALARM_ID+" integer primary key AUTOINCREMENT, "+KEY_DESC+" TEXT, "+KEY_REPEAT_DAY+ " TEXT,"
+KEY_REPEAT_TYPE+" integer, "+KEY_CALENDAR+" TEXT, "+KEY_APP+" TEXT, "+KEY_ACTIVE+" integer );";
db.execSQL(CREATE_TABLE);
}
//updating database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
// Create tables again
onCreate(db);
}
public void addAlarm(Alarm alarm)
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_DESC, alarm.getDesc());
values.put(KEY_REPEAT_DAY, alarm.getRepeatDay());
values.put(KEY_REPEAT_TYPE, alarm.getRepeatType());
values.put(KEY_CALENDAR, Long.toString(alarm.getCalendarInMillis()));
values.put(KEY_APP, alarm.getApp());
values.put(KEY_ACTIVE, alarm.getActive());
db.insert(TABLE_NAME, null, values);
db.close();
}
不知道是什么问题。所以我发布了 Logcat:
03-13 17:09:33.388: D/SqliteDatabaseCpp(1095): Registering sqlite logging func: /data/data/com.example.devicecontrolpanel/databases/AlarmSystem
03-13 17:09:33.408: D/SqliteDatabaseCpp(1095): DB info: open db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, flag = 6, cannot stat file, errno = 2, message = No such file or directory
03-13 17:09:33.408: D/SqliteDatabaseCpp(1095): DB info: path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle: 0x8ccc98, type: w, r/w: (0,1), mode: truncate, disk free size: 777 M
03-13 17:09:33.588: D/SqliteDatabaseCpp(1095): DB info: close db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle = 0x8ccc98, type = w, r/w = (0, 0)
03-13 17:09:33.588: D/SqliteDatabaseCpp(1095): DB info: open db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, flag = 6, file size = 4096
03-13 17:09:33.588: D/SqliteDatabaseCpp(1095): DB info: path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle: 0x8f3100, type: w, r/w: (0,1), mode: truncate, disk free size: 777 M
03-13 17:09:33.588: D/SqliteDatabaseCpp(1095): DB info: close db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle = 0x8f3100, type = w, r/w = (0, 0)
03-13 17:09:33.598: D/AndroidRuntime(1095): Shutting down VM
03-13 17:09:33.598: W/dalvikvm(1095): threadid=1: thread exiting with uncaught exception (group=0x40ae0228)
03-13 17:09:33.618: E/AndroidRuntime(1095): FATAL EXCEPTION: main
03-13 17:09:33.618: E/AndroidRuntime(1095): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.devicecontrolpanel/com.example.devicecontrolpanel.Main}: java.lang.IllegalStateException: database /data/data/com.example.devicecontrolpanel/databases/AlarmSystem (conn# 0) already closed
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2205)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2240)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread.access$600(ActivityThread.java:139)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1262)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.os.Handler.dispatchMessage(Handler.java:99)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.os.Looper.loop(Looper.java:156)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread.main(ActivityThread.java:4987)
03-13 17:09:33.618: E/AndroidRuntime(1095): at java.lang.reflect.Method.invokeNative(Native Method)
03-13 17:09:33.618: E/AndroidRuntime(1095): at java.lang.reflect.Method.invoke(Method.java:511)
03-13 17:09:33.618: E/AndroidRuntime(1095): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
03-13 17:09:33.618: E/AndroidRuntime(1095): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
03-13 17:09:33.618: E/AndroidRuntime(1095): at dalvik.system.NativeStart.main(Native Method)
03-13 17:09:33.618: E/AndroidRuntime(1095): Caused by: java.lang.IllegalStateException: database /data/data/com.example.devicecontrolpanel/databases/AlarmSystem (conn# 0) already closed
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteDatabase.verifyDbIsOpen(SQLiteDatabase.java:2194)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:448)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:435)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:79)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:176)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:168)
03-13 17:09:33.618: E/AndroidRuntime(1095): at com.example.devicecontrolpanel.DataBaseAdapter.getAlarmsCount(DataBaseAdapter.java:190)
03-13 17:09:33.618: E/AndroidRuntime(1095): at com.example.devicecontrolpanel.DataBaseAdapter.getAllAlarmList(DataBaseAdapter.java:117)
03-13 17:09:33.618: E/AndroidRuntime(1095): at com.example.devicecontrolpanel.Main.onCreate(Main.java:19)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.Activity.performCreate(Activity.java:4538)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1071)
03-13 17:09:33.618: E/AndroidRuntime(1095): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2161)
03-13 17:09:33.618: E/AndroidRuntime(1095): ... 11 more
03-13 17:16:48.144: D/SqliteDatabaseCpp(2080): Registering sqlite logging func: /data/data/com.example.devicecontrolpanel/databases/AlarmSystem
03-13 17:16:48.144: D/SqliteDatabaseCpp(2080): DB info: open db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, flag = 6, cannot stat file, errno = 2, message = No such file or directory
03-13 17:16:48.164: D/SqliteDatabaseCpp(2080): DB info: path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle: 0x86b220, type: w, r/w: (0,1), mode: truncate, disk free size: 777 M
03-13 17:16:48.384: D/SqliteDatabaseCpp(2080): DB info: close db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle = 0x86b220, type = w, r/w = (0, 0)
03-13 17:16:48.384: D/SqliteDatabaseCpp(2080): DB info: open db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, flag = 6, file size = 5120
03-13 17:16:48.384: D/SqliteDatabaseCpp(2080): DB info: path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle: 0x897800, type: w, r/w: (0,1), mode: truncate, disk free size: 777 M
03-13 17:16:48.384: D/SqliteDatabaseCpp(2080): DB info: close db, path = /data/data/com.example.devicecontrolpanel/databases , key = 9lYvmWqw, handle = 0x897800, type = w, r/w = (0, 0)
03-13 17:16:48.394: D/AndroidRuntime(2080): Shutting down VM
03-13 17:16:48.414: W/dalvikvm(2080): threadid=1: thread exiting with uncaught exception (group=0x40ae0228)
03-13 17:16:48.424: E/AndroidRuntime(2080): FATAL EXCEPTION: main
03-13 17:16:48.424: E/AndroidRuntime(2080): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.devicecontrolpanel/com.example.devicecontrolpanel.Main}: java.lang.IllegalStateException: database /data/data/com.example.devicecontrolpanel/databases/AlarmSystem (conn# 0) already closed
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2205)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2240)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread.access$600(ActivityThread.java:139)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1262)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.os.Handler.dispatchMessage(Handler.java:99)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.os.Looper.loop(Looper.java:156)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread.main(ActivityThread.java:4987)
03-13 17:16:48.424: E/AndroidRuntime(2080): at java.lang.reflect.Method.invokeNative(Native Method)
03-13 17:16:48.424: E/AndroidRuntime(2080): at java.lang.reflect.Method.invoke(Method.java:511)
03-13 17:16:48.424: E/AndroidRuntime(2080): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
03-13 17:16:48.424: E/AndroidRuntime(2080): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
03-13 17:16:48.424: E/AndroidRuntime(2080): at dalvik.system.NativeStart.main(Native Method)
03-13 17:16:48.424: E/AndroidRuntime(2080): Caused by: java.lang.IllegalStateException: database /data/data/com.example.devicecontrolpanel/databases/AlarmSystem (conn# 0) already closed
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteDatabase.verifyDbIsOpen(SQLiteDatabase.java:2194)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:448)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteDatabase.lock(SQLiteDatabase.java:435)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:79)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:176)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:168)
03-13 17:16:48.424: E/AndroidRuntime(2080): at com.example.devicecontrolpanel.DataBaseAdapter.getAlarmsCount(DataBaseAdapter.java:196)
03-13 17:16:48.424: E/AndroidRuntime(2080): at com.example.devicecontrolpanel.DataBaseAdapter.getAllAlarmList(DataBaseAdapter.java:123)
03-13 17:16:48.424: E/AndroidRuntime(2080): at com.example.devicecontrolpanel.Main.onCreate(Main.java:19)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.Activity.performCreate(Activity.java:4538)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1071)
03-13 17:16:48.424: E/AndroidRuntime(2080): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2161)
03-13 17:16:48.424: E/AndroidRuntime(2080): ... 11 more
最佳答案
一般来说，最好将包装器方法(在您的情况下为 addAlarm, editAlarm, deleteAlarm )分离到一个单独的类中。我建议您创建一个名为 myAppDataSource 的新类，并在该类中添加所有包装器方法，让您的生活更轻松。
该类的代码如下所示:
public class StudyManagerDataSource {
SQLiteOpenHelper dbHelper;
SQLiteDatabase database;
public StudyManagerDataSource(Context context) {
dbHelper = new DatabaseAdapter(context);
}
public void addAlarm(Alarm alarm)
{
// open the database connection
open();
ContentValues values = new ContentValues();
values.put(KEY_DESC, alarm.getDesc());
values.put(KEY_REPEAT_DAY, alarm.getRepeatDay());
values.put(KEY_REPEAT_TYPE, alarm.getRepeatType());
values.put(KEY_CALENDAR, Long.toString(alarm.getCalendarInMillis()));
values.put(KEY_APP, alarm.getApp());
values.put(KEY_ACTIVE, alarm.getActive());
database.insert(TABLE_NAME, null, values);
// I will suggest to keep the connection to the database open when your app is
// running, the recommended time to close the connection is when your app is
//going to pause/stop.
close();
}
public void open() {
database = dbHelper.getWritableDatabase();
Log.i(LOG_TAG, "Database Opened");
} // end method open
public void close() {
Log.i(LOG_TAG, "Database Closed");
dbHelper.close();
} // end method close
}
关于java - Android SQLite ContentValues 不插入，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15384550/
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