Android使用TypeFace设置TextView的文字字体

import android.app.Activity;
import android.graphics.Typeface;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import com.example.memorydemo.R;
 
public class ChangeFontActivity extends Activity implements View.OnClickListener {
  private TextView textViewFont;
 
  @Override
  protected void onCreate(Bundle onSavedInstance) {
    super.onCreate(onSavedInstance);
    setContentView(R.layout.change_textview_font);
 
    textViewFont = findViewById(R.id.textViewFont);
    Button btnChangeFont = findViewById(R.id.buttonChangeFont);
    Button btnAmplify = findViewById(R.id.buttonAmplify);
    btnChangeFont.setOnClickListener(this);
    btnAmplify.setOnClickListener(this);
  }
 
  @Override
  public void onClick(View view) {
    switch (view.getId()) {
      case R.id.buttonChangeFont:
 
        // 这里我是从Android framework目录下随便挑了一种字体
        textViewFont.setTypeface(Typeface.createFromAsset(getAssets(), "fonts/BitMDL2.ttf"));
 
        // 直接将 ttf 文件放在 assets 目录下也是可以的
        // textViewFont.setTypeface(Typeface.createFromAsset(getAssets(), "BitMDL2.ttf"));
        break;
 
      case R.id.buttonAmplify:
        // 布局里面默认大小是 12 SP，这里将字体大小设置为 24 SP，方便看效果
        textViewFont.setTextSize(24);
        break;
 
      default:
        break;
    }
  }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:orientation="vertical" >
 
  <TextView android:layout_width="wrap_content" android:layout_height="60dp"
       android:id="@+id/textViewFont" android:layout_gravity="center"
       android:text="This is a Font"
       android:textSize="12sp"
       android:paddingTop="20dp"/>
 
  <Button
      android:text="换字体"
      android:layout_width="wrap_content"
      android:layout_gravity="center"
      android:layout_height="60dp" android:id="@+id/buttonChangeFont" />
  <Button
      android:text="变大"
      android:layout_width="wrap_content"
      android:layout_gravity="center"
      android:layout_marginTop="15dp"
      android:layout_height="60dp" android:id="@+id/buttonAmplify" />
</LinearLayout>