Question

This function returns a 0.0 althought all the values are float and are retrieved correctly from the shared preferences ! what could be the error?

float BMR(){

    SharedPreferences customSharedPreference = getSharedPreferences(
                "myCustomSharedPrefs", Activity.MODE_PRIVATE);

    String  Weight =customSharedPreference.getString("weightpref", null);
    float weight = Float.valueOf(Weight);

    String  Height = customSharedPreference.getString("heightpref",null);
    float height = Float.valueOf(Height);
    String Age = customSharedPreference.getString("agepref", null);
    float age = Float.valueOf(Age);

    int gender = customSharedPreference.getInt("genderpref", 0);

    Toast.makeText(StatsActivity.this, Age, Toast.LENGTH_LONG).show();
    if ( gender == 0){
        bmr = (float) (10.0 *weight + 6.25 * height - 5.0 * age + 5.0);
    }
    if(gender == 1){
        bmr = (float) (10.0 * weight + 6.25 * height - 5.0 * age- 161.0);
    }

    String bmrtest = String.valueOf(bmr);
    Toast.makeText(StatsActivity.this, "bmr is "+bmrtest, Toast.LENGTH_LONG).show();
    return bmr;
    }

Answer 1

What happens if gender is not 0 or 1? Your bmr would remain unassigned (to 0.0).

If that’s the problem, you may consider, for the future, to:

• put an else clause after your if’s
• group those two ifs into an elseif (since they are exclusive)
• at the very least put in an assert to check that gender is indeed 1 or 0