Andorid 修改字体一文打尽

/**
 * 设置自定义字体
 *
 * @param context
 * @param staticTypefaceFieldName 需要替换的系统字体样式
 * @param fontAssetName           替换后的字体样式
 */
public static void setDefaultFont(Context context, String staticTypefaceFieldName, String fontAssetName) {
    // 根据路径得到Typeface
    Typeface regular = Typeface.createFromAsset(context.getAssets(), fontAssetName);
    // 设置全局字体样式
    replaceFont(staticTypefaceFieldName, regular);
}

private static void replaceFont(String staticTypefaceFieldName, final Typeface newTypeface) {
    try {
        final Field staticField = Typeface.class.getDeclaredField(staticTypefaceFieldName);
        staticField.setAccessible(true);
        //替换系统字体样式
        staticField.set(null, newTypeface);
    } catch (NoSuchFieldException e) {
        e.printStackTrace();
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    }
}

<style name="YourTheme" parent="AppTheme.Base">
    <item name="android:typeface" >serif</item>
</style>

<application xmlns:tools="http://schemas.android.com/tools"
    ...
    android:theme="@style/YourTheme"
    tools:replace="android:theme">
    ...
</application>

TextView textView = (TextView) findViewById(R.id.textView_font);
Typeface typeface = ResourcesCompat.getFont(this, R.font.myfont);
textView.setTypeface(typeface);