Android中如何让文字淡入淡出

Android中如何让文字淡入淡出？

xml
    android:id="@+id/textView"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Hello World!"
    android:textSize="24sp"
    android:alpha="0" />

java
TextView textView = findViewById(R.id.textView);
AlphaAnimation animation = new AlphaAnimation(0, 1);
animation.setDuration(1000);
textView.startAnimation(animation);

xml
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
            android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        android:textSize="24sp"
        android:alpha="0" />

java
import android.os.Bundle;
import android.view.animation.AlphaAnimation;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView textView = findViewById(R.id.textView);
        AlphaAnimation animation = new AlphaAnimation(0, 1);
        animation.setDuration(1000);
        textView.startAnimation(animation);
    }
}