allprojects {
  repositories {
    ...
    maven { url 'https://jitpack.io' }
  }
}

dependencies {
  implementation 'com.github.andreasagap:LoadingButtonLibrary:v1.0'
}

<android.support.constraint.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:id="@+id/root"
    android:layout_height="match_parent">

    <andreasagap.loadingbutton.ButtonLoading
        android:id="@+id/loadingbutton"
        android:layout_width="match_parent"
        android:layout_height="48dp"
        app:BL_backgroundColor="#9c9b9999"
        app:BL_backgroundDisableColor="#00AFEF"
        app:BL_circleColor="#00AFEF"
        app:BL_circleColorSecond="#8000AFEF"
        app:BL_enable="true"
        app:BL_stateShow="normal"
        app:BL_text="Login"
        app:BL_textColor="#ffffff"
        app:BL_textDisableColor="#000000"
        app:BL_textSize="16sp"/>

</android.support.constraint.ConstraintLayout>

ConstraintLayout root=findViewById(R.id.root);
ButtonLoading buttonLoading=findViewById(R.id.loadingbutton);
buttonLoading.setRoot(buttonLoading,this,root);
buttonLoading.setOnButtonLoadingListener(new ButtonLoading.OnButtonLoadingListener() {
    @Override
    public void onClick() {
                //...
    }
    @Override
    public void onStart() {

                //...
    }
    @Override
    public void onFinish() {
                //...

    }
});