KotlinNullPointerException: inside onCreateOptionsMenu can't find searchView; android

Question

I need MainActivity with SearchView, it throws KotlinNullPointerException: inside onCreateOptionsMenu; here is my code:

options_menu.xml

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

<item
    android:id="@+id/search"
    android:actionViewClass="android.widget.SearchView"
    android:icon="@android:drawable/ic_menu_search"
    app:showAsAction="collapseActionView|ifRoom"
    android:title="@string/search" />
</menu>

MainActivity.java

import android.text.TextUtils
import android.view.Menu
import android.widget.AdapterView
import android.widget.SearchView
import android.widget.Toast
...
import kotlinx.android.synthetic.main.activity_main.*
import android.app.SearchManager
import android.content.Context


override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    logd("onCreate MainActivity")
    setSupportActionBar(toolbar)
    ...
} 
...
override fun onCreateOptionsMenu(menu: Menu): Boolean {
    menuInflater.inflate(R.menu.options_menu, menu)
    val searchManager = getSystemService(Context.SEARCH_SERVICE) as SearchManager
    val searchView = menu.findItem(R.id.search).actionView as? SearchView
    searchView!!.setSearchableInfo(searchManager.getSearchableInfo(componentName))
    return true
}

i am using custom toolbar like this but i think problem is not here

Answer 1

Change android:actionViewClass="android.widget.SearchView" to app:actionViewClass="android.widget.SearchView" it will work fine.

Answer 2

问题出在app：actionViewClass

中

<item
    android:id="@+id/itemSearch"
    android:icon="@drawable/ic_search"
    android:title="Search"
    app:actionViewClass="android.support.v7.widget.SearchView"
    app:showAsAction="collapseActionView|ifRoom" />

你必须使actionViewClass在Activity

中相同

import android.support.v7.widget.SearchView

MainActivity从AppCompatActivity扩展而来 AppCompatActivity也像那样导入

import android.support.v7.app.AppCompatActivity

我希望在这里支持每个人

最好的问候