javaでボタンタップ時にアニメーションが呼ばれない

Rotateanimationのアニメーションが起動時のときはアニメーションが実行されるのにonClickLitnerでのボタンタップ時にはアニメーションが実行されない

java
1
2package com.example.test;
3
4import
5        androidx.appcompat.app.AppCompatActivity;
6
7import android.graphics.Canvas;
8import android.graphics.Color;
9import android.graphics.Point;
10import android.os.Bundle;
11import android.util.Log;
12import android.view.ViewGroup;
13import android.view.animation.Animation;
14import android.view.animation.RotateAnimation;
15import android.widget.Button;
16import android.widget.LinearLayout;
17import android.widget.TextView;
18
19
20public class MainActivity extends AppCompatActivity {
21    MyView myView;
22    Button btn;
23    @Override
24    protected void onCreate(Bundle savedInstanceState) {
25        super.onCreate(savedInstanceState);
26        LinearLayout main=new LinearLayout(this);
27        LinearLayout.LayoutParams mainparam=new 
28        LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 
29        ViewGroup.LayoutParams.MATCH_PARENT);
30
31        main.setLayoutParams(mainparam);
32        main.setBackgroundColor(Color.WHITE);
33        main.setOrientation(LinearLayout.VERTICAL);
34
35        LinearLayout.LayoutParams btnparam=new 
36        LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 
37        ViewGroup.LayoutParams.MATCH_PARENT,1.0f);
38
39        myView = new MyView(this);
40        myView.setLayoutParams(btnparam);
41
42        btn=new Button(this);
43        btn.setLayoutParams(btnparam);
44        btn.setText(R.string.text4);
45        btn.setBackgroundColor(Color.BLACK);
46      
47        btn.setOnClickListener(v->{
48             this.tap();
49        });
50        main.addView(myView);
51        main.addView(btn);
52        setContentView(main);
53   }
54 void tap(){
55        RotateAnimation ani =new RotateAnimation(0.0f,20000.0f, 
56        Animation.RELATIVE_TO_SELF,0.5f,Animation.RELATIVE_TO_SELF,0.5f);
57        ani.setDuration(5000);
58        ani.setRepeatCount(0);
59        ani.setFillAfter(true);
60        myView.setAnimation(ani);
61    }
62}