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# compose

[Ali]

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[jamshedalamqaderi]

First of all remember is a composable function. So, you can only call it from Composable functions

[Ali]

I am following the android documentation for this, and it does not have any compose on the class. https://developer.android.com/develop/ui/compose/quick-guides/content/validate-input

[jamshedalamqaderi]

in the documentation remember is not used. it's just mutableStateOf

[Ali]

Yes man, i did not notice that. Thanks so much.

[Ali]

the error is still there even though I removed it.

var email by mutableStateOf("")

[jamshedalamqaderi]

Hover the mouse over the error and import if anything is suggested.

[Ali]

When i hover on the error it shows me this below message
"Type 'androidx. compose. runtime. MutableState<kotlin. String>' has no method 'getValue(EmailViewModel, KMutableProperty1<*, *>)', so it cannot serve as a delegate.

Type 'androidx. compose. runtime. MutableState<kotlin. String>' has no method 'setValue(EmailViewModel, KMutableProperty1<*, *>, ERROR CLASS: Unresolved name: getValue)', so it cannot serve as a delegate for var (read-write property)."

[jamshedalamqaderi]

import androidx.compose.runtime.getValue
Add this import

[jamshedalamqaderi]

by the this 4 imports need to be added

import androidx.compose.runtime.getValue
import androidx.compose.runtime.setValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.derivedStateOf

[Ali]

Yup, i added these both and it worked.

import androidx.compose.runtime.getValue
import androidx.compose.runtime.setValue

Why it could not imported auto?

[jamshedalamqaderi]

these are delegations to set and get values when you use by

[jamshedalamqaderi]

So, these are the difference of using delegation

var email:String by mutableStateOf("")
    val email2: MutableState<String> = mutableStateOf("")

    init{
        email = "[e-mail]"
        email2.value = "[e-mail]"
    }

[Ali]

Its helpful - thanks