<@U0129FYHT54> Hi, you don’t define aLiveData ```...

# announcements

[Platon Malyugin]

@KayCee Hi, you don’t define aLiveData

lateinit var aLiveData: LiveData<List<..>>
aLiveData = // define live data
val list = aLiveData.value

[KayCee]

thank you, of course I did define that in my code. The point to focus is why the line "val list = aLiveData.value" can cause crash

[akatkov]

If you call aLiveData.value before you assign aLiveData = ... Then it'll be null and crash

[akatkov]

If aLiveData isn't guaranteed to be initialized before you use it, you should make it nullable instead

[KayCee]

aLiveData = getListFromDb()
yeah, thats right but in that case the " lateinit exception" will be presented not NPE? since there is no lateinit exception, so I think in my code the "getListFromDb()" return a null livedata? That seems unreasonable with the query:

@Query("SELECT * FROM table")
fun getListFromDb(): LiveData<List<DataA>>

[Vampire]

Put a breakpoint and see what is happening