Kotlin: Make the options menu visible only in a specific toolbar

Question

There are three types of toolbar used in this app. (toolbar, toolbar2, toolbar3)

The MainActivity is connected to four fragments through the bottom navigation bar. (home, community, calendar, mypage)

toolbar - used in "MainActivity" (home, community, calendar, mypage)

toolbar2 - used when navigating to MainActivity -> "NoticeFragment"

toolbar3 - used when navigating to MainActivity -> CommunityFragment -> "CommunityItemFragment"

I want to put the option menu in toolbar3 only.

However, if I write onCreateOptionsMenu in the MainActivity, an option menu created only in toolbar.

How do I solve this problem?

<activity_main.xml>

<?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">

    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:minHeight="?attr/actionBarSize"
        android:theme="?attr/actionBarTheme"
        android:visibility="visible"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent"></androidx.appcompat.widget.Toolbar>

    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:minHeight="?attr/actionBarSize"
        android:theme="?attr/actionBarTheme"
        android:visibility="invisible"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent"></androidx.appcompat.widget.Toolbar>

    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:minHeight="?attr/actionBarSize"
        android:theme="?attr/actionBarTheme"
        android:visibility="invisible"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent"></androidx.appcompat.widget.Toolbar>

<MainActivity.kt>

class MainActivity : AppCompatActivity() {
    lateinit var binding: ActivityMainBinding

    private val fl: FrameLayout by lazy {
        findViewById(R.id.main_frm)
    }

    private var backPressedTime : Long = 0

    @SuppressLint("MissingInflatedId")

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

        replaceFragment(NaviCommunityFragment())

        val main_bnv = findViewById<BottomNavigationView>(R.id.main_bnv)
        setSupportActionBar(toolbar)
        supportActionBar?.setDisplayShowTitleEnabled(false)

        var noticeitem = findViewById<ImageView>(R.id.noticeitem)
        var toolbar = findViewById<Toolbar>(R.id.toolbar)
        var toolbar2 = findViewById<Toolbar>(R.id.toolbar2)
        var toolbar3 = findViewById<Toolbar>(R.id.toolbar3)

        close_notice.setOnClickListener {
            val transaction = supportFragmentManager.popBackStack()
            toolbar.visibility = View.VISIBLE
            toolbar2.visibility = View.INVISIBLE
            toolbar3.visibility = View.INVISIBLE
        }

        noticeitem.setOnClickListener{
            val transaction = supportFragmentManager.beginTransaction()
                .replace(R.id.main_frm, NoticeFragment())
                .addToBackStack(null)
            transaction.commit()
            toolbar.visibility = View.INVISIBLE
            toolbar2.visibility = View.VISIBLE
            toolbar3.visibility = View.INVISIBLE
        }

        btn_back.setOnClickListener {
            val transaction = supportFragmentManager.popBackStack()
            toolbar.visibility = View.VISIBLE
            toolbar2.visibility = View.INVISIBLE
            toolbar3.visibility = View.INVISIBLE
        }

        main_bnv.setOnItemSelectedListener { item ->
            changeFragment(
                when (item.itemId) {
                    R.id.navigation_home -> {
                        main_bnv.itemIconTintList = null
                        main_bnv.itemTextColor  = null
                        NaviHomeFragment()
                    }
                    R.id.navigation_community -> {

                        main_bnv.itemIconTintList = null
                        NaviCommunityFragment()
                    }
                    R.id.navigation_calendar -> {
                        main_bnv.itemIconTintList = null
                        Calendar_fragment()
                    }
                    else -> {
                        main_bnv.itemIconTintList = null
                        NaviMypageFragment()
                    }
                }
            )
            true
        }
        main_bnv.selectedItemId = R.id.navigation_home
    }


    private fun changeFragment(fragment: Fragment) {
        supportFragmentManager.popBackStackImmediate()
        supportFragmentManager
            .beginTransaction()
            .replace(R.id.main_frm, fragment)
            .commit()
    }


    private fun replaceFragment(naviCommunityFragment: Fragment){
        val fragmentManager = supportFragmentManager
        val fragmentTransaction = fragmentManager.beginTransaction()
        fragmentTransaction.replace(R.id.main_frm, naviCommunityFragment)
        fragmentTransaction.commit()
    }

    override fun onCreateOptionsMenu(menu: Menu?): Boolean {
        menuInflater.inflate(R.menu.toolbar3_menu, menu)
        return super.onCreateOptionsMenu(menu)
    }

}

<NaviCommunityAdapter.kt>

override fun onBindViewHolder(holder: NaviCommunityViewHolder, position: Int) {
                holder.title.text = itemList[position].title
                holder.nickname.text = itemList[position].nickname
                
                holder.itemView.setOnClickListener(object : View.OnClickListener{
                        override fun onClick(p0: View?) {
                                val activity=p0!!.context as AppCompatActivity
                                
                                val communityItemFragment = CommunityItemFragment()
                                activity.supportFragmentManager.beginTransaction().replace(R.id.main_frm, communityItemFragment)
                                        .addToBackStack(null).commit()
                                activity.toolbar.visibility = View.INVISIBLE
                                activity.toolbar3.visibility = View.VISIBLE
                        }
                })
        }

I thought that using onCreateOptionsMenu in MainActivity would have an option menu in all toolbars.

So I wanted to make the option menu only when toolbar3 is visible.

However, option menus are created only in toolbar, and not in toolbar2 or toolbar3.

Answer 1

For my solution first you have to create a static Menu in your main activity:

public static Menu your_menu;

After that you have to saved that menu with your menu

@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.toolbar3_menu, menu);
        your_menu = menu;
        return super.onCreateOptionsMenu(menu);
    }

Then in your fragment if you want to show it just call it and set its visible to true

Like if you want your menu to show only in CommunityItemFragment then in that fragment set it

MainActivity.your_menu.setVisible(true);

and set it to false in other fragements or just set it false with check fragment condition in your MainActivity