Refresh MainActivity page when checkbox is checked in activity_main file

I have a Unitconverter.java file which converts Kelvin to Celsius and Kelvin to Fahrenheit:

package com.sg.blabla;

import android.content.SharedPreferences;
import java.util.Locale;

public class UnitConvertor {
    public static float convertTemperature(float temperature, SharedPreferences sp) {
        if (sp.getString("unit", "C").equals("°C")) {
            return UnitConvertor.kelvinToCelsius(temperature);
        } else if (sp.getString("unit", "C").equals("°F")) {
            return UnitConvertor.kelvinToFahrenheit(temperature);
        } else {
            return temperature;
        }
    }

    public static float kelvinToCelsius(float kelvinTemp) {
        return kelvinTemp - 273.15f;
    }

    public static float kelvinToFahrenheit(float kelvinTemp) {
        return (((9 * kelvinToCelsius(kelvinTemp)) / 5) + 32);
    }
}

I have a MainActivity.java activity file which will convert tempature based on user input when checkbox is checked:

float temperature = UnitConverter.convertTemperature(Float.parseFloat(todayWeather.getTemperature()), sp);
if (sp.getBoolean("temperatureInteger", false)) {
    temperature = Math.round(temperature);
}

public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    if (id == R.id.action_refresh) {
        if (isNetworkAvailable()) {
            getTodayWeather();
            getLongTermWeather();
        }
        return true;
    }
}

I have a activity_main.xml file which has the following code:

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://ift.tt/nIICcg">
    <PreferenceCategory android:title="@string/settings_title_units">
        <ListPreference
            android:defaultValue="C"
            android:entries="@array/temperatureUnits"
            android:entryValues="@array/temperatureUnitsValues"
            android:key="unit"
            android:title="@string/setting_tempUnits" />

        <CheckBoxPreference
            android:defaultValue="false"
            android:key="temperatureInteger"
            android:title="@string/setting_showTempAsInteger" />
    </PreferenceCategory>
</PreferenceScreen>

I have a arrays.xml file which has the following code:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="temperatureUnits">
        <item name="C">@string/setting_unit_Celsuis</item>
        <item name="F">@string/setting_unit_Fahrenheit</item>
        <item name="K">@string/setting_unit_Kelvin</item>
    </string-array>
    <string-array name="temperatureUnitsValues">
        <item name="C">°C</item>
        <item name="F">°F</item>
        <item name="K">K</item>
    </string-array>
</resources>

I have a menu.xml file which has the following code:

<menu xmlns:android="http://ift.tt/nIICcg"
    xmlns:app="http://ift.tt/GEGVYd"
    xmlns:tools="http://ift.tt/LrGmb4"
    tools:context=".activities.MainActivity">
    <item
        android:id="@+id/action_refresh"
        android:icon="@drawable/ic_refresh_white_24dp"
        android:title="@string/action_refresh"
        app:showAsAction="always" />
</menu>

Currently, after I check the checkbox in layout file, I need to go to the MainActivity page and and then if I click on Refresh, only then the MainActivity page will reflect the temperature which I had checked through checkbox.

But my problem is when the checkbox is checked in layout file, automatically the MainActivity page should get refreshed.