آموزش تغییر فونت تمام قسمت های برنامه بوسیله کتابخانه Calligraphy

import uk.co.chrisjenx.calligraphy.CalligraphyConfig;
import android.app.Activity;
import android.app.Application;
import android.content.Context;
import android.content.SharedPreferences;
import android.graphics.Typeface;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Handler;
import android.preference.PreferenceManager;
import android.view.LayoutInflater;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;


public class G extends Application {

    public static Context           context;
    public static LayoutInflater    inflater;
    public static final Handler     HANDLER     = new Handler();
    public static Activity          currentActivity;
    public static SharedPreferences preference;
    public static String            encodedHash = Uri.encode("#");

    public static Typeface          amerfont;
    public static Typeface          arabicfont;
    public static Typeface          arabicbfont;
    public static Typeface          koodakfont;
    public static Typeface          narmfont;
    public static Typeface          yekanfont;
    public static Typeface          byekanfont;
    public static Typeface          iranfont;
    public static Typeface          yekanmob;

    
    public static int               id;
    public static int               number;

    public static EditText          edtNumberMobile;
    public static EditText          edtNumberCard;

    public static TextView          txtCheckNet;
    public static ImageView         imgNewNews;
    public static ImageView         imgProfileMenubar;


    @Override
    public void onCreate() {
        super.onCreate();

        context = getApplicationContext();
        inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        preference = PreferenceManager.getDefaultSharedPreferences(this);

        amerfont = Typeface.createFromAsset(getAssets(), "amer.ttf");
        arabicfont = Typeface.createFromAsset(getAssets(), "arabic.ttf");
        arabicbfont = Typeface.createFromAsset(getAssets(), "arabicb.ttf");
        koodakfont = Typeface.createFromAsset(getAssets(), "koodak.ttf");
        narmfont = Typeface.createFromAsset(getAssets(), "narm.ttf");
        yekanfont = Typeface.createFromAsset(getAssets(), "yekan.ttf");
        byekanfont = Typeface.createFromAsset(getAssets(), "byekan.ttf");
        iranfont = Typeface.createFromAsset(getAssets(), "iran.ttf");
        yekanfont = Typeface.createFromAsset(getAssets(), "yekanfont.ttf");

        CalligraphyConfig.initDefault(new CalligraphyConfig.Builder()
                .setDefaultFontPath("iran.ttf")
                .build()
                );


    }


    //////////////////////////check internet connection
    public static boolean isNetworkConnected() {
        ConnectivityManager cm = (ConnectivityManager) G.context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo ni = cm.getActiveNetworkInfo();

        if (ni == null) {
            // There are no active networks.
            return false;
        } else
            return true;
    }

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