I’m opening this discussion because I need help for a school project.

At the moment, I have a scrollable activity with some buttons, everything is built like this:
a constraint layout, with SearchView, ScrollView and a BottomNavigationBar, and inside the ScrollView there’s a LinearLayout with all my buttons.

Here is the full xml file:

<?xml version="1.0" encoding="utf-8"?>


<androidx.constraintlayout.widget.ConstraintLayout xmlns:tools="http://schemas.android.com/tools"
    android:layout_height="match_parent"
    android:layout_width="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">


    <SearchView
        android:id="@+id/BarraRicerca"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_marginTop="10dp"
        android:gravity="top"
        android:iconifiedByDefault="false"
        android:imeOptions="actionDone"
        android:queryHint="Cerca un tutorial"
        android:labelFor="@id/BarraRicerca"
        android:suggestionRowLayout="@color/white"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />


    <ScrollView
        android:id="@+id/scrollView2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_weight="1"
        android:fillViewport="false"
        android:orientation="vertical"
        android:padding="10dp"
        android:layout_marginTop="60dp"
        app:layout_constraintBottom_toTopOf="@id/BottomBar"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/BarraRicerca">


        <LinearLayout
            android:id="@+id/Linearlayout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"
            tools:context="com.example.Flipper.FlipperList">

            <Button
                android:id="@+id/FlintstonesF"
                android:layout_width="300dp"
                android:layout_height="49dp"
                android:layout_gravity="center_horizontal"
                android:layout_margin="100dp"
                android:text="Flintstones" />

            <Button
                android:id="@+id/tutorial2"
                android:layout_width="300dp"
                android:layout_height="49dp"
                android:layout_gravity="center_horizontal"
                android:layout_margin="200dp"
                android:layout_weight="1"
                android:text="ciao" />

            <Button
                android:id="@+id/tutorial3"
                android:layout_width="300dp"
                android:layout_height="49dp"
                android:layout_gravity="center_horizontal"
                android:layout_margin="100dp"
                android:layout_weight="1"
                android:text="hello" />

        </LinearLayout>

    </ScrollView>

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/BottomBar"
        android:layout_width="0dp"
        android:layout_height="60dp"
        android:layout_marginStart="0dp"
        android:layout_marginEnd="0dp"
        android:layout_gravity="bottom"
        android:background="?android:attr/windowBackground"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"/>


</androidx.constraintlayout.widget.ConstraintLayout>

and the result is this, everything works

Now I need to implement the SearchView to actually search through my buttons, For example if I search Flintstones (or Flint, or Fli etc.) I want the Flintstones button to be the only one shown. The same goes for “ciao” and so on, I will obviously have more buttons than these.

I tried every possible solution I found on the internet but nothing seems to work. This is my code

package com.example.Flipper

import android.content.Intent
import android.os.Bundle
import android.view.View
import android.widget.*
import androidx.appcompat.app.AppCompatActivity
import androidx.core.view.isVisible
import com.example.pinballacademy.R


class FlipperList : AppCompatActivity() {
    val passaFlintstones: Button get() = findViewById(R.id.FlintstonesF)
    val bottone2: Button get() = findViewById(R.id.tutorial2)
    val bottone3: Button get() = findViewById(R.id.tutorial3)
    val searchbar: SearchView get() = findViewById(R.id.BarraRicerca)
    val linLay: LinearLayout get() = findViewById(R.id.Linearlayout)

    var listaFlipper: ArrayList<String> = ArrayList()


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_flipper_list)






        /*    listaFlipper.clear();
            listaFlipper.add(passaFlintstones.text.toString())
            listaFlipper.add(bottone2.text.toString())
            listaFlipper.add(bottone3.text.toString())*/

            searchbar.isSubmitButtonEnabled=true




           searchbar.setOnQueryTextListener() {

                 fun onQueryTextChange(newText: String?): Boolean {
                    filter(newText)
                    return true
                }

                 fun onQueryTextSubmit(query: String?): Boolean {
                    filter(query)
                    return true
                }

                    // Do your task here


                }


        passaFlintstones.setOnClickListener()
        {
            val intent = Intent(this, FlintstonesScheda::class.java)
            //avvia registrazione
            startActivity(intent)
            // finish()
        }

    }

    fun filter(searchText: String?) {
        for (i in 0 until linLay.childCount) {
            val button: Button = linLay.getChildAt(i) as Button
            if (button.text.toString().contains(searchText!!)) {
                button.isVisible=true
            } else button.isVisible=false
        }
    }


    private fun SearchView.setOnQueryTextListener(function: () -> Unit) {

    }
}

As you can see I’m not even near to a solution, I hope you can help! Thank you!