Android - Using Custom Font

Well, after seven years you can change whole app textView or what you want easily by using android.support libraries 26++.

E.g:

Create your font package app/src/res/font and move your font into it.

And in your app theme just add it as a fontFamily:

    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
   . . . ...
    <item name="android:fontFamily">@font/demo</item>
</style>

Example for use with textView only:

<style name="fontTextView" parent="@android:style/Widget.TextView">
    <item name="android:fontFamily">monospace</item>
</style>

And add into your main theme:

<item name="android:textViewStyle">@style/fontTextView</item>

Currently it's worked on 8.1 until 4.1 API Jelly Bean And that's a wide range.

Update answer: Android 8.0 (API level 26) introduces a new feature, Fonts in XML. just use the Fonts in XML feature on devices running Android 4.1 (API level 16) and higher, use the Support Library 26.

see this link

Old answer

There are two ways to customize fonts :

!!! my custom font in assets/fonts/iran_sans.ttf

Way 1 : Refrection Typeface.class ||| best way

call FontsOverride.setDefaultFont() in class extends Application, This code will cause all software fonts to be changed, even Toasts fonts

AppController.java

public class AppController extends Application {

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

        //Initial Font
        FontsOverride.setDefaultFont(getApplicationContext(), "MONOSPACE", "fonts/iran_sans.ttf");

    }
}

FontsOverride.java

public class FontsOverride {

    public static void setDefaultFont(Context context, String staticTypefaceFieldName, String fontAssetName) {
        final Typeface regular = Typeface.createFromAsset(context.getAssets(), fontAssetName);
        replaceFont(staticTypefaceFieldName, regular);
    }

    private static void replaceFont(String staticTypefaceFieldName, final Typeface newTypeface) {
        try {
            final Field staticField = Typeface.class.getDeclaredField(staticTypefaceFieldName);
            staticField.setAccessible(true);
            staticField.set(null, newTypeface);
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }
}

Way 2: use setTypeface

for special view just call setTypeface() to change font.

CTextView.java

public class CTextView extends TextView {

    public CTextView(Context context) {
        super(context);
        init(context,null);
    }

    public CTextView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
        init(context,attrs);
    }

    public CTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context,attrs);
    }

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    public CTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init(context,attrs);
    }

    public void init(Context context, @Nullable AttributeSet attrs) {

        if (isInEditMode())
            return;

        // use setTypeface for change font this view
        setTypeface(FontUtils.getTypeface("fonts/iran_sans.ttf"));

    }
}

FontUtils.java

public class FontUtils {

    private static Hashtable<String, Typeface> fontCache = new Hashtable<>();

    public static Typeface getTypeface(String fontName) {
        Typeface tf = fontCache.get(fontName);
        if (tf == null) {
            try {
                tf = Typeface.createFromAsset(AppController.getInstance().getApplicationContext().getAssets(), fontName);
            } catch (Exception e) {
                e.printStackTrace();
                return null;
            }
            fontCache.put(fontName, tf);
        }
        return tf;
    }

}

The correct way of doing this as of API 26 is described in the official documentation here :

https://developer.android.com/guide/topics/ui/look-and-feel/fonts-in-xml.html

This involves placing the ttf files in res/font folder and creating a font-family file.

• Open your project and select Project on the top left
• app --> src --> main
• right click to main and create directory name it as assets
• right click to assest and create new directory name it fonts
• you need to find free fonts like free fonts
• give it to your Textview and call it in your Activity class
• copy your fonts inside the fonts folder
• TextView txt = (TextView) findViewById(R.id.txt_act_spalsh_welcome); Typeface font = Typeface.createFromAsset(getAssets(), "fonts/Aramis Italic.ttf"); txt.setTypeface(font);

name of the font must be correct and have fun