Activity or Fragment

public class BaseActivity extends Activity implements DetectsSoftKeyboardLayout.OnSoftKeyboardListener 
{
  DetectsSoftKeyboardLayout rootlayout;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        rootLayout.setOnSoftKeyboardListener(this);
  }
  
   @Override
    public void onShown() {
      Log.d(TAG, "onShown: ");
      // keyboard visible  
    }

    @Override
    public void onHidden() {
      Log.d(TAG, "onHidden: ");
      // keyboard hidden  
    }
}

DetectsSoftKeyboardLayout

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.RelativeLayout;


public class DetectsSoftKeyboardLayout extends RelativeLayout {
  private static final String TAG = "DetectsSoftKeyboardLayo";

  public DetectsSoftKeyboardLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  public DetectsSoftKeyboardLayout(Context context) {
    super(context);
  }

  private OnSoftKeyboardListener onSoftKeyboardListener;

  @Override protected void onMeasure(final int widthMeasureSpec, final int heightMeasureSpec) {
    if (onSoftKeyboardListener != null) {
      final int newSpec = MeasureSpec.getSize(heightMeasureSpec);
      final int oldSpec = getMeasuredHeight();
      if (oldSpec == 0) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        return;
      }
      Log.d(TAG, "onMeasure: new " + newSpec);
      Log.d(TAG, "onMeasure: old " + oldSpec);
      int diff = newSpec - oldSpec;
      if (Math.abs(diff) < 200) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        return;
      }
      if (diff < 0) {
        Log.d(TAG, "onMeasure: shown");
        onSoftKeyboardListener.onShown();
      } else if (diff > 0) {
        Log.d(TAG, "onMeasure: hidden");
        onSoftKeyboardListener.onHidden();
      }
    }
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
  }

  public final void setOnSoftKeyboardListener(final OnSoftKeyboardListener listener) {
    this.onSoftKeyboardListener = listener;
  }

  public interface OnSoftKeyboardListener {
    void onShown();

    void onHidden();
  }
}

Layout file

<mywidget.DetectsSoftKeyboardLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/baseRootLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

  <!-- your layout -->  
    
</mywidget.DetectsSoftKeyboardLayout>