Retrieve number from android preferences

Question

I'm probably missing something basic here, but I'm still a beginner. I have looked up a ton of websites but I can't seem to make any of those fixes work. I have a preference fragment that the user can input their hourly wage (among other things). I have an activity that is supposed to use that preference in a calculation, but I'm continually getting a 0 returned. Here's the code:

public class StartCalc extends Activity implements OnSharedPreferenceChangeListener {
static final String TAG = "StartCalc";

Date time_o, time_f;
float money_o = 0, money_f = 0, hoursToday = 0, hoursTotal = 0, payscale;
SharedPreferences prefs;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    prefs = PreferenceManager.getDefaultSharedPreferences(this);
    prefs.registerOnSharedPreferenceChangeListener(this);

    payscale = prefs.getFloat("PAYSCALE", 0);
}

public float CalculateWeekly() {

        Log.d(TAG, "Calculating normaltime pay");
        float pay = 10 * payscale; // testing with 10 instead of hours
        // total
        Log.d(TAG, Double.toString(payscale)); //always getting 0.0
        return pay;

}

In my starting activity I have a toggle button that's supposed to calculate pay earned by comparing your hours worked to the payscale set in the preferences.

@Override
public void onClick(View v) {
    boolean on = ((ToggleButton) v).isChecked();
    StartCalc session = new StartCalc();
    Intent timeServiceIntent = new Intent(this, TimeService.class);

    if (on == true) {
        button = true;
        Log.d(TAG, "Button Clicked");
        // session.TimeClock();
        startService(timeServiceIntent);
    } else {
        button = false;
        // Log.d(TAG, "Not Running");
        // session.CalculateWeekly();
        try {
            tvTotal.setText(Float.toString(session.CalculateWeekly()));
        } catch (Exception e) {
            Log.d(TAG, "Set text didn't work...");
            e.printStackTrace();

        }
        Toast.makeText(Home.this, "Calculating...", Toast.LENGTH_SHORT).show();
    }

}

Answer 1

Well...

You can't really instantiate activities like that, when you call new StartCalc() it doesnt call the onCreateMethod and payscale is 0.

I dont even see a point to your StartCalc extending Activity since you're not setting a contentView, was it to get the context? You can get the context in other ways, try this instead:

public class StartCalc implements OnSharedPreferenceChangeListener {
static final String TAG = "StartCalc";

Date time_o, time_f;
float money_o = 0, money_f = 0, hoursToday = 0, hoursTotal = 0, payscale;
SharedPreferences prefs;
private Context context;

public StartCalc(Context context) {
    this.context = context;
    prefs = PreferenceManager.getDefaultSharedPreferences(context);
    prefs.registerOnSharedPreferenceChangeListener(this);

    payscale = prefs.getFloat("PAYSCALE", 0);
}

public float calculateWeekly() { //its good practice to start method names with lower case

        Log.d(TAG, "Calculating normaltime pay");
        float pay = 10 * payscale; // testing with 10 instead of hours
        // total
        Log.d(TAG, Double.toString(payscale)); //always getting 0.0
        return pay;
}

Then on your onClick method try this:

@Override
public void onClick(View v) {
    boolean on = ((ToggleButton) v).isChecked();
    StartCalc session = new StartCalc(MainActivity.this); //im assuming its called main activity
    Intent timeServiceIntent = new Intent(this, TimeService.class);

    if (on == true) {
        button = true;
        Log.d(TAG, "Button Clicked");
        // session.TimeClock();
        startService(timeServiceIntent);
    } else {
        button = false;
        // Log.d(TAG, "Not Running");
        // session.calculateWeekly();
        try {
            tvTotal.setText(Float.toString(session.CalculateWeekly()));
        } catch (Exception e) {
            Log.d(TAG, "Set text didn't work...");
            e.printStackTrace();

        }
        Toast.makeText(Home.this, "Calculating...", Toast.LENGTH_SHORT).show();
    }

}