lateinit property has not been initialized
Solution 1
If you don't want to use any thirdparty libraries, you can add these extension functions (I tend to have a ContextExtensions.kt
or ViewExtensions.kt
for Context or View related extension functions), then put in it
inline fun <reified T : View> View.find(id: Int): T = findViewById(id) as T
inline fun <reified T : View> Activity.find(id: Int): T = findViewById(id) as T
inline fun <reified T : View> Fragment.find(id: Int): T = view?.findViewById(id) as T
these let you call find
from within Activity
, Fragment
, and View
s.
So inside your class instead of
@BindView(R.id.menu_title_text_view_id) lateinit var menuTitleTextView : CTextBasic
you can have
val menuTitleTextView by lazy { find<CTextBasic>(R.id.menu_title_text_view_id) }
For things like UIs, it's better to val
instead of var
when they don't need to change. As a general rule in programming, try to keep things as immutable as possible, you would get far less bugs.
Solution 2
I found this works for me.
Change your build.gradle
in your project app
module.
dependencies {
compile "com.jakewharton:butterknife:8.8.1"
kapt "com.jakewharton:butterknife-compiler:8.8.1"
}
use kapt
instead of annotationProcessor
.
and then you can do your familiar ButterKnife annotation like this:
class MainActivity : AppCompatActivity() {
@BindView(R.id.myButton)
lateinit var myButton: Button
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
ButterKnife.bind(this)
//...
}
}
Enjoy.
Solution 3
add apply plugin: 'kotlin-kapt'
to the app level build.gradle file
example
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
and in dependencies section
implementation "com.jakewharton:butterknife:8.8.1"
kapt "com.jakewharton:butterknife-compiler:8.8.1"
Hope this Helps!
Solution 4
Use Kotterknife for Butter Knife-esque View Binding for Kotlin.
Then you can bind your View with
val menuTitleTextView: CTextBasic by bindView(R.id.menu_title_text_view_id)
Solution 5
In my case, I wasn't building ButterKnife correctly. Make sure you're importing its compiler in your module's build.gradle:
...
// Butter Knife
implementation "com.jakewharton:butterknife:$butterKnifeVersion"
kapt "com.jakewharton:butterknife-compiler:$butterKnifeVersion"
...
The discussion at Jetbrain's samples thread shed more light on this issue for me.
Another issue is that you might be accessing the views before the container has been created. Here is a related question, the discussion there is specific to kotlinx synthetic properties but same logic should apply to Butterknife view binding
Comments
-
Jemo Mgebrishvili about 3 years
I have a custom linearlayout class and when I want to create instance of this class, I get the following error:
lateinit property has not been initializedI'm using the latest version of butterknife library.
The following is my Kotlin class:
class MenuItemView : LinearLayout { @BindView(R.id.menu_title_text_view_id) lateinit var menuTitleTextView : CTextBasic constructor(ctx: Context) : super(ctx) { } init { val view = LayoutInflater.from(context).inflate(R.layout.menu_item,this) ButterKnife.bind(this,view) } constructor(ctx: Context, attrs: AttributeSet) : super(ctx, attrs) { val menuAttrs = context.theme.obtainStyledAttributes(attrs, R.styleable.MenuItemView, 0, 0) try { val title: String = menuAttrs.getString(R.styleable.MenuItemView_menu_title) menuTitleTextView.text = title }catch (e : Exception){ e.printStackTrace() }finally { menuAttrs.recycle() } } fun setTitle( title : String){ menuTitleTextView.text = title } }
Error Log
kotlin.UninitializedPropertyAccessException: lateinit property menuTitleTextView has not been initialized at com.leavigstone.liberali.ui.custom.menu.MenuItemView.setTitle(MenuItemView.kt:48) at com.leavigstone.liberali.ui.activities.MainActivity.onAddButtonClick(MainActivity.java:142) at com.leavigstone.liberali.ui.activities.MainActivity_ViewBinding$3.doClick(MainActivity_ViewBinding.java:54) at butterknife.internal.DebouncingOnClickListener.onClick(DebouncingOnClickListener.java:22) at android.view.View.performClick(View.java:4780) at android.view.View$PerformClick.run(View.java:19866) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5254) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)