android - Gettine 异常 : java. lang.IllegalStateException:数据库未打开

Question

虽然这是一个常见的错误，并且可能有很多帖子与此异常相关。但这是奇怪的情况。我在 Android 2.2 中收到 java.lang.IllegalStateException: database not open 异常。在其余手机中，它运行良好。

日志:

java.lang.IllegalStateException: database not open
at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1291)
at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1251)
at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1331)
at com.mythrii.ilpa.DataHelper.checkRating(DataHelper.java:126)
at com.mythrii.ilpa.SplashActivity$1.run(SplashActivity.java:35)
at android.os.Handler.handleCallback(Handler.java:587)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:144)
at android.app.ActivityThread.main(ActivityThread.java:4937)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
at dalvik.system.NativeStart.main(Native Method)

我的代码:

public class SplashActivity extends ActivityHelper
{
private DataHelper dh;
// Set the display time, in milliseconds (or extract it out as a configurable parameter)
private final int SPLASH_DISPLAY_LENGTH = 3000;
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.act__splash);

    dh = new DataHelper(this);

    dh.inserORupdateRating();
}

protected void onResume()
{
    super.onResume();

        new Handler().postDelayed(new Runnable()
        {
            public void run()
            {
                clearPref();
                PrefBoolEdit("rating",dh.checkRating());//=> Here is the exception
                SplashActivity.this.finish();
                Intent mainIntent = new Intent(SplashActivity.this, HomeActivity.class);
                SplashActivity.this.startActivity(mainIntent);
            }
        }, SPLASH_DISPLAY_LENGTH);

}

protected void onDestroy() 
{
    super.onDestroy();
    if (dh != null) 
    {
        dh.close();
    }
}
}

我正在使用这个构造函数来调用每个 Activity

数据助手

 public DataHelper(Context context) 
   {

      this.context  =   context;
      openHelper    =   new OpenHelper(this.context);
      this.db       =   openHelper.getWritableDatabase();

      Calendar c = Calendar.getInstance();    
      formattedDate = df.format(c.getTime());
   }

检查评级

   public boolean checkRating()
   {
       Cursor cursor = this.db.query(TABLE_NAME_1, new String[] { "option" },
               null, null, null, null, null);

       String option = null;
       //String date = null;

       boolean bool = false;

       if (cursor.moveToFirst())
          {
              do {
                  //date     = cursor.getString(0);
                  option = cursor.getString(0);

               } while (cursor.moveToNext());
          }
          if (cursor != null && !cursor.isClosed()) {
              cursor.close();
          }

          if(getRateCount()>0)
          {
              if(!option.equals(ALREADY_RATED))
              {
                  bool = true;
              }
              else 
              {
                  bool = false;
              }
          }
          else 
          {
                bool = false;
          }  
       return bool;
   }

谁能帮帮我..

Answer 1

在执行任何操作之前你应该打开数据库

dh.open();

See this one 和 also this one