No type arguments expected for class Flow

Question

I encountered a problem with Kotlin Flow.

I copied the following code code from the Official guide

fun simple(): Flow<Int> = flow { 
    for (i in 1..3) {
        delay(100) 
        emit(i) 
    }
}

But the Android Studio prompts a following error:

No type arguments expected for class Flow

What am I doing wrong?

score 91 · Accepted Answer · answered Nov 24 '21 at 12:07

91

Make sure you use import kotlinx.coroutines.flow.Flow not java.util.concurrent.Flow, it gives you this error because Java concurrent Flow class take 0 type arguments, but Coroutines Flow take one

answered Nov 24 '21 at 12:07

AmrDeveloper

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3

you're right，thanks! – 巴赫哥德尔 Nov 24 '21 at 12:18
1

I also had to change the version of Kotlin coroutines from 1.6.0 to 1.5.2. – Saleem Dec 09 '21 at 17:48
This has worked for me. – Josphat Mwania May 20 '23 at 07:48

No type arguments expected for class Flow

1 Answers1