Java 当耗时的代码完成时，Circular ProgressIndicator显示得太晚

I am trying to show a progress indicator in some time consuming code but the screen is not refreshed while the code is running. After the code is finished it animates the indicator.
The solution is probably simple for an experienced android developer which I am not.
I created a minimum code application to show the problem

activity_main. html:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:background="@android:color/black">
        <Button
            android:id="@+id/button"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textColor="#FFFFFF"
            android:textSize="18sp"
            android:text="Start"
            tools:ignore="HardcodedText" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="horizontal">
            <com.google.android.material.progressindicator.CircularProgressIndicator
                android:id="@+id/cpi"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:progress="0"
                android:useLevel="true"
                android:visibility="visible"
                app:indicatorColor="#FF0000"
                app:indicatorSize="95dp"
                app:trackColor="#606060"
                app:trackCornerRadius="5dp"
                app:trackThickness="16dp"
                tools:layout_editor_absoluteX="157dp"
                tools:layout_editor_absoluteY="108dp" />
        </LinearLayout>
    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java:

package com.hennep.testcircularprogress;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.os.Handler;
import com.google.android.material.progressindicator.CircularProgressIndicator;

public class MainActivity extends AppCompatActivity {
    int iProgress = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final Button button = findViewById(R.id.button);
        final CircularProgressIndicator progress = findViewById(R.id.cpi);

        Handler handler = new Handler();
        new Thread(new Runnable() {
            @Override
            public void run() {
                while (true ) {
                    handler.postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            progress.setProgress(iProgress,true);
                        }
                    },100 );
                    try {
                        Thread.sleep(100);
                    } catch (InterruptedException e ) {
                        e.printStackTrace();
                    }
                }
            }
        }).start();


        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v ) {
                iProgress = 0;
                //progress.setVisibility( CircularProgressIndicator.VISIBLE );
                button.setText("Calculating...");
                for( int k = 0; k < 192; k++ ) {
                    Thread.yield();
                    for( int fk = 1; fk <= 1000; fk *= 10 ) {
                        for( int j = 0; j < 192; j++ ) {
                            for( int fj = 1; fj <= 1000; fj *= 10 ) {
                                for( int i = 0; i < 192; i++ ) {
                                    for( int fi = 1; fi <= 1000; fi *= 10 ) {
                                        // Calculate E192 three resistor resistive divider here, not relevant for the test
                                        iProgress = k;
                                    }
                                }
                            }
                        }
                    }
                }
                button.setText("Start");
                //progress.setVisibility( CircularProgressIndicator.GONE );
            }
        });        
    }
}

而且按钮上的文本也没有改变，我预计也是同样的问题.