How to properly retrieve data from SearchView in Kotlin?

Question

I'm working on a personal project where I want to use a searchbar. I've been checking other post for my problem but I still don't understand what's going on.

I know that "searchView" is not referenced, but I don't know what to put instead... Every time I use "searchView", android studio tells me : "Unsolved References"

    //retrieve search query
    override fun onCreateOptionsMenu(menu: Menu): Boolean {
        menuInflater.inflate(R.menu.my_menu, menu)
        val searchItem = menu.findItem(R.id.app_bar_search)
        searchView = searchItem.actionView as SearchView
        searchView.setQueryHint("Search View Hint")
        searchView.setOnQueryTextListener(object :  SearchView.OnQueryTextListener {

            override fun onQueryTextChange(newText: String): Boolean {
                return false
            }

            override fun onQueryTextSubmit(query: String): Boolean {
                // task HERE
                //on submit send entire query
                return false
            }

        })

        return true
    }

Here is my menu xml:

<menu xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:android="http://schemas.android.com/apk/res/android">

    <item
            android:id="@+id/app_bar_search"
            android:icon="@drawable/ic_search_black_24dp"
            android:title="Search"
            app:showAsAction="always"
            app:actionViewClass="android.widget.SearchView"/>
</menu>

And here the toolbar xml:

    <androidx.appcompat.widget.Toolbar
            android:id="@+id/toolbarHome"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            android:elevation="4dp"
            android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

Feel free to ask me anything.

Answer 1

You need to define your searchView as a val: val searchView = searchItem.actionView as SearchView. I removed the default Toolbar in the style.xml to use yours (see onCreate method). With this code I can compile and type some text in the searchbar.

Activity.kt

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

override fun onCreateOptionsMenu(menu: Menu): Boolean {
    menuInflater.inflate(R.menu.my_menu, menu)
    val searchItem = menu.findItem(R.id.app_bar_search)
    val searchView = searchItem.actionView as SearchView
    searchView.queryHint = "Search View Hint"
    searchView.setOnQueryTextListener(object :  SearchView.OnQueryTextListener {

        override fun onQueryTextChange(newText: String): Boolean {
            return false
        }

        override fun onQueryTextSubmit(query: String): Boolean {
            // task HERE
            //on submit send entire query
            return false
        }

    })

    return true
}

my_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:app="http://schemas.android.com/apk/res-auto"
      xmlns:android="http://schemas.android.com/apk/res/android">

    <item
            android:id="@+id/app_bar_search"
            android:title="Search"
            app:showAsAction="always"
            app:actionViewClass="androidx.appcompat.widget.SearchView"/>
</menu>

toolbar

<androidx.appcompat.widget.Toolbar
    android:id="@+id/toolbarHome"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:background="?attr/colorPrimary"
    android:elevation="4dp"
    android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light"/>

style.xml

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
        <item name="windowActionBar">false</item>
    </style>

</resources>