Answers for "how to do a specific text bold in android xml"

android font bold xml

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textStyle="bold"
    android:text="@string/app_name"
    android:layout_gravity="center" 
/>

how to set text style to bold in android programmatically

textView.setTypeface(null, Typeface.BOLD_ITALIC);
textView.setTypeface(null, Typeface.BOLD);
textView.setTypeface(null, Typeface.ITALIC);
textView.setTypeface(null, Typeface.NORMAL);