Android: extending android.app.Application
I have a DBHandler class that will be used in several activi开发者_如何学运维ties to do some crud operations. created a MyApp class (extends Application) to hold one instantiation of the DBHandler.
My DBHandler class needs a Context to create the SQLiteOpenHelper to populate the db, etc.
That's where the problem starts: in my MyApp constructor, I want to instantiate my DBHandler, so I wrote this:
public MyApp() {
super();
dbh = DBHandler(<WHAT DO I PASS HERE>);
}
I tried getApplicationContext(), getBaseContext(), 'this'... nothing seems to be a fully-instantiated context at this point. I get a NPE when the SQLiteOpenHelper tries ctx.getResources().
A workaround: create the DBHandler and set it in the onCreate of my main class. -> UGLY (call me a aesthetician)
Question: is there a way to do it when Android creates MyApp?
Thanks!
Creating your DBHandler in MyApp.onCreate() is the proper way to do what you want.
@Override
public void onCreate() {
super.onCreate();
dbh = new DBHandler(this);
}
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