Dynamic multiple button dialog

import android.animation.AnimatorInflater;
import android.animation.StateListAnimator;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Context;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.DialogFragment;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import com.fieldbuzz.utilities.validator_utility.Validator;
import com.fieldbuzz.widgets.R;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

public class DynamicMultipleButtonDialogBuilder extends DialogFragment  {

    public static final String POP_UP_DIALOG = "pop_alert_dialog";
    public static String DIALOG_TITLE = "dialog-title";
    public static String DIALOG_MESSAGE = "dialog-message";
    public static String DIALOG_BUTTON_LIST = "dialog-button-list";

    private static DynamicMultipleButtonDialogBuilder dynamicMultipleButtonDialogBuilder;


    List<ButtonItem> buttonItems;
    String title;
    String message;
    FragmentManager fragmentManager;
    private Context context;

    public static DynamicMultipleButtonDialogBuilder getInstance(){
            dynamicMultipleButtonDialogBuilder = new DynamicMultipleButtonDialogBuilder();
            return dynamicMultipleButtonDialogBuilder;
    }
    public DynamicMultipleButtonDialogBuilder(){
        buttonItems = new ArrayList<>();
    }
    
    
    public DynamicMultipleButtonDialogBuilder setButtonItem(ButtonItem buttonItem) {
        this.buttonItems.add(buttonItem);
        return this;
    }

    public DynamicMultipleButtonDialogBuilder setMessage(String message) {
        this.message=message;
        return this;
    }

    public DynamicMultipleButtonDialogBuilder setTitle(String title) {
        this.title=title;
        return this;
    }
    public DynamicMultipleButtonDialogBuilder setFragmentManager(FragmentManager fragmentManager) {
        this.fragmentManager=fragmentManager;

        FragmentTransaction mFragmentTransaction = fragmentManager.beginTransaction();
        Fragment fragment = fragmentManager.findFragmentByTag(POP_UP_DIALOG);

        // Remove it if found
        if (fragment != null) {
            mFragmentTransaction.remove(fragment);
        }
        mFragmentTransaction.commitAllowingStateLoss();

        return this;

    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        context = getActivity();

        if (getArguments() != null) {
            title = getArguments().getString(DIALOG_TITLE, "");
            message = getArguments().getString(DIALOG_MESSAGE, "");
            buttonItems = (ArrayList<ButtonItem>) getArguments().getSerializable(DIALOG_BUTTON_LIST);
        }

        AlertDialog.Builder builder = new AlertDialog.Builder(context);
        AlertDialog alertDialog = builder.create();
        alertDialog.setView(createView());
        alertDialog.setCancelable(false);

        return alertDialog;
    }

    private View createView() {
        View mView;
        mView = LayoutInflater.from(context).inflate(R.layout.dialog_dynamic_multiple_button, null);
        TextView tvTitle = mView.findViewById(R.id.tv_dialog_title);
        TextView tvMessage = mView.findViewById(R.id.tv_dialog_message);

        if (Validator.isValid(title)) {
            tvTitle.setText(title);
        } else tvTitle.setVisibility(View.GONE);
        if (Validator.isValid(message)) {
            tvMessage.setText(message);
        } else tvMessage.setVisibility(View.GONE);

        RecyclerView recyclerView = mView.findViewById(R.id.rv_list);

        GridLayoutManager gridLayoutManager = new GridLayoutManager(getContext(),2);
        
        //It make the last button "Match parent" for balancing the UI
        gridLayoutManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() {
            @Override
            public int getSpanSize(int position) {
                if (buttonItems.size() % 2 != 0) {
                    return (position == buttonItems.size() - 1) ? 2 : 1;
                } else {
                    return 1;
                }
            }
        });

        recyclerView.setLayoutManager(gridLayoutManager);
        ButtonAdapter buttonAdapter = new ButtonAdapter();
        buttonAdapter.setButtonItemList(buttonItems);
        recyclerView.setAdapter(buttonAdapter);


        return mView;
    }


    public class ButtonAdapter extends RecyclerView.Adapter<ButtonViewHolder> {
        List<ButtonItem> buttonItemList;
        ButtonClickListener buttonClickListener;

        public ButtonClickListener getButtonClickListener() {
            return buttonClickListener;
        }

        public void setButtonClickListener(ButtonClickListener buttonClickListener) {
            this.buttonClickListener = buttonClickListener;
        }

        public List<ButtonItem> getButtonItemList() {
            return buttonItemList;
        }

        public void setButtonItemList(List<ButtonItem> buttonItemList) {
            this.buttonItemList = buttonItemList;
        }

        @NonNull
        @Override
        public ButtonViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int position) {
            View itemView = LayoutInflater.from(viewGroup.getContext())
                    .inflate(R.layout.item_multiple_dynamic_button_dialog, viewGroup, false);

            return new ButtonViewHolder(itemView);
        }



        @Override
        public void onBindViewHolder(@NonNull ButtonViewHolder buttonViewHolder, int position) {
            if(position>=0){
              ButtonItem buttonItem =  buttonItemList.get(position);
              buttonViewHolder.button.setText(buttonItem.getName());
              buttonViewHolder.button.setBackgroundColor(buttonItem.getBgColor());
              buttonViewHolder.button.setTextColor(buttonItem.getTextColor());
              if(buttonItem.getBgDrawable()!=null)
              buttonViewHolder.button.setBackground(buttonItem.getBgDrawable());
              else buttonViewHolder.button.setBackgroundColor(buttonItem.getBgColor());
            }


            buttonViewHolder.button.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    buttonItemList.get(position).buttonClickListener.
                            onButtonClick(dynamicMultipleButtonDialogBuilder);
                }
            });

        }

        @Override
        public int getItemCount() {
            return buttonItemList.size();
        }

    }
    class ButtonViewHolder extends RecyclerView.ViewHolder {
        Button button;
        public ButtonViewHolder(@NonNull View itemView) {
            super(itemView);
            button=itemView.findViewById(R.id.btn_item);
        }
    }
     public void build()
     {
         Bundle args = new Bundle();
         args.putString(DIALOG_TITLE, title);
         args.putString(DIALOG_MESSAGE, message);
         args.putSerializable(DIALOG_BUTTON_LIST,(Serializable)buttonItems);
         dynamicMultipleButtonDialogBuilder.setArguments(args);

         if(dynamicMultipleButtonDialogBuilder.isVisible())
             dynamicMultipleButtonDialogBuilder.dismiss();
         dynamicMultipleButtonDialogBuilder.show(fragmentManager,POP_UP_DIALOG);
     }


    public static class ButtonItem implements Serializable {

        String name;
        int bgColor;
        int textColor;
        Drawable bgDrawable;
        ButtonClickListener buttonClickListener;

        public ButtonItem(String name,Drawable bgDrawable, int textColor,  ButtonClickListener buttonClickListener) {
            this.name = name;
            this.textColor = textColor;
            this.bgDrawable = bgDrawable;
            this.buttonClickListener = buttonClickListener;
        }

        public Drawable getBgDrawable() {
            return bgDrawable;
        }

        public void setBgDrawable(Drawable bgDrawable) {
            this.bgDrawable = bgDrawable;
        }

        public int getTextColor() {
            return textColor;
        }

        public void setTextColor(int textColor) {
            this.textColor = textColor;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public int getBgColor() {
            return bgColor;
        }

        public void setBgColor(int bgColor) {
            this.bgColor = bgColor;
        }

        public ButtonClickListener getButtonClickListener() {
            return buttonClickListener;
        }

        public void setButtonClickListener(ButtonClickListener buttonClickListener) {
            this.buttonClickListener = buttonClickListener;
        }
        public ButtonItem(String name, int bgColor, int textColor, ButtonClickListener buttonClickListener) {
            this.name = name;
            this.bgColor = bgColor;
            this.textColor = textColor;
            this.buttonClickListener = buttonClickListener;
        }
    }

    public interface ButtonClickListener {
        void onButtonClick(DynamicMultipleButtonDialogBuilder dynamicMultipleButtonDialogBuilder);
    }

}


///Dialog XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="match_parent"
	android:layout_height="wrap_content"
	android:background="@drawable/bg_rectangle_solid_button_white">

	<LinearLayout
		android:id="@+id/layout_child"
		style="@style/childLayoutTheme"
		android:layout_width="match_parent"
		android:layout_height="wrap_content"
		android:layout_alignParentTop="true"
		android:orientation="vertical">

		<TextView
			android:id="@+id/tv_dialog_title"
			style="@style/textStyleLarge"
			android:layout_width="match_parent"
			android:layout_height="wrap_content"
			android:gravity="center_horizontal"
			android:layout_marginBottom="8dp"
			android:textStyle="bold" />

		<View
			android:layout_width="match_parent"
			android:layout_height="2dp"
			android:layout_marginBottom="8dp"
			android:background="@color/colorPrimary" />

		<TextView
			android:id="@+id/tv_dialog_message"
			style="@style/textStyleLarge"
			android:layout_width="match_parent"
			android:layout_height="match_parent"
			android:gravity="center_horizontal"
			android:textStyle="normal" />
	</LinearLayout>

	<android.support.v7.widget.RecyclerView
		android:id="@+id/rv_list"
		android:layout_width="match_parent"
		android:layout_height="wrap_content"
		android:layout_below="@+id/layout_child"
		android:layout_centerInParent="true">
	</android.support.v7.widget.RecyclerView>
</RelativeLayout>
///Dialog XML


///Dialog button item
<?xml version="1.0" encoding="utf-8"?>
    <Button
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:gravity="center"
        android:id="@+id/btn_item"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="@dimen/_10sdp">
    </Button>
///Dialog button item