没有为参数项传递值 [英] No value passed for parameter item
问题描述
你好,我有这个代码:
override fun onCreateOptionsMenu(menu: Menu): Boolean {
menuInflater.inflate(R.menu.menu_search, menu)
val searchItem = menu.findItem(R.id.action_search)
val searchView = MenuItemCompat.getActionView() as SearchView
//*** setOnQueryTextFocusChangeListener ***
searchView.setOnQueryTextFocusChangeListener(object : View.OnFocusChangeListener {
override fun onFocusChange(v: View, hasFocus: Boolean) {
}
})
searchView.setOnQueryTextListener(object : SearchView.OnQueryTextListener {
override fun onQueryTextSubmit(query: String): Boolean {
return false
}
override fun onQueryTextChange(searchQuery: String): Boolean {
adapter!!.filter(searchQuery.trim { it <= ' ' })
tvListAnimal.invalidate()
return true
}
})
return true
}
我在这一行中发现了一个错误:val searchView = MenuItemCompat.getActionView() as SearchView
.其实这只是代码的开始.确实 Android Studio 告诉我 No value传递给参数 item
但我真的不知道我必须放什么?
And I found a bug in this line : val searchView = MenuItemCompat.getActionView() as SearchView
. Actually it is just the beginning of the code. Indeed Android Studio told me No value passed for parameter item
but I don't really know what I have to put ?
非常感谢您的帮助!真的!
Thank a lot for your help ! Really !
这里是 menu_search.xml :
EDIT : here is the menu_search.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"
xmlns:tools="http://schemas.android.com/tools"
tools:context=".SettingsFragment">
<item android:id="@+id/action_search"
android:title="Search"
android:icon="@drawable/ic_search"
app:showAsAction="collapseActionView|always"
app:actionViewClass="android.support.v7.widget.SearchView"
android:layout_width="wrap_content" />
</menu>
我在 logcat 中找到了这个:
I found this in the logcat :
java.lang.ClassCastException: android.support.v7.widget.SearchView cannot be cast to android.widget.SearchView
推荐答案
问题在于MenuItemCompat.getActionView()
需要将MenuItem
作为参数传入:
The problem is that MenuItemCompat.getActionView()
requires the MenuItem
to be passed in as a parameter:
val searchView = MenuItemCompat.getActionView(searchItem) as SearchView
如果这在您使用的 Android 版本中已弃用(如此处所见),您应该改用它:
If this is depracated in the Android version you're using (as seen here), you should use this instead:
val searchView = searchItem.getActionView() as SearchView
这篇关于没有为参数项传递值的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!