CODEWITHSUNDEEP
androidmultithreading
Deano
Deano

Reputation: 176

calling method in a separate class

I have my main class setup and a worker thread, one of my early requests that I make in run() is to call my second class called login. I do this like so:

    login cLogin = new login();
    cLogin.myLogin();

class login looks like this:

package timer.test;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.widget.Toast;

public class login extends Activity {

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

    public void myLogin() {
        // prepare the alert box
        AlertDialog.Builder alertbox = new AlertDialog.Builder(this);

        // set the message to display
        alertbox.setMessage(this.getString(R.string.intro));

        // add a neutral button to the alert box and assign a click listener
        alertbox.setNeutralButton("Register New Account",
                new DialogInterface.OnClickListener() {

                    // click listener on the alert box
                    public void onClick(DialogInterface arg0, int arg1) {
                        // the button was clicked
                    }
                });

        // add a neutral button to the alert box and assign a click listener
        alertbox.setNegativeButton("Login",
                new DialogInterface.OnClickListener() {

                    // click listener on the alert box
                    public void onClick(DialogInterface arg0, int arg1) {
                        // the button was clicked
                    }
                });

        // show it
        alertbox.show();

    }

10-01 14:33:33.028: ERROR/AndroidRuntime(440):
  java.lang.RuntimeException: Unable to start activity ComponentInfo{timer.test/timer.test.menu}:
   java.lang.IllegalStateException:
    System services not available to Activities before onCreate()

I put onCreate in but still having the same problem. How can I fix this?

Upvotes: 1

Views: 272

Answers (2)

Rejinderi
Rejinderi

Reputation: 11844

You cannot do it this way simply because you are using the context

 AlertDialog.Builder alertbox = new AlertDialog.Builder(this); //this is the activity context passed in..

The context is not available until Activity onCreate is called via startActivity. and not by constructing an new instance of the login object, you can try passing in an context from the activity calling this method

public void myLogin(Context context) {
    // prepare the alert box
    AlertDialog.Builder alertbox = new AlertDialog.Builder(context);
    //blah blah blah...
}

yes and never construct an activity instance via the constructor.. -.-

Upvotes: 1

Jesper Bischoff-Jensen
Jesper Bischoff-Jensen

Reputation: 1490

You have a couple of options:

1) Move your public void myLogin() {..} to your main activity. I recommend this solution since you don't need another activity for your purposes.

2) Call startActivity on your login class before calling the myLogin(). Since you inherite from Activity onCreate needs to be called before you call anything else. That's why you get the exception. startActivity is called like this: 

    Intent i = new Intent(this, login.class);  
    startActivity(i);

Upvotes: 1

Related Questions