通过检查Android SDK中的数据库进行首次设置

Question

My application will show a first time setup screen when the user opens it for the first time. I need to know when it is the first time the application is executed and my question is:

Should I do this by checking and changing a flag setting in SharedPreferences or is it more secure to check if the database is empty (I use SQLiteOpenHelper )? In the last case, how can I check if the database is empty?

Answer 1

SharedPreferences will most likely be quicker, but if you want to check for an empty database:

Cursor cursor = db.rawQuery("SELECT COUNT(*) FROM TABLE_NAME", null);
if (cursor != null){
    cursor.moveToFirst();
    if (cursor.getInt(0) == 0) {
      // It is Empty 
    }
}

where TABLE_NAME is the name of a table (that should be populated) in your database. The only concern I have with the database is if you end up changing what and when something is populated, potentially resulting in the app failing to know the correct time to show the set-up screen - a single boolean SharedPreferences flag might be simpler.