REACT NATIVE - this.setState doesn't work inside onChangeText - reactjs

Question

I'm trying to create a conditional onPress here using a gender selection. If the gender is undefined, I can't go on. Quite simple. But I'm a newbie and I'm not finding the trouble here.
That's the gender prop in state...
constructor(props) {
super(props);
this.state = {
gender: ''
};
That's the const genderSelect with these 3 gender values...
render() {
const genderSelected = [
{ value: 'Feminino', label: 'Feminino' },
{ value: 'Masculino', label: 'Masculino' },
{ value: 'Outro', label: 'Outro' }
];
...
}
That's my Dropdown class where I call the genderSelect and try to use the setState (but it doesn't work, the 'console.log' keeps returning 'undefined'). And finally, that's my conditional onPress.
return (
<>
<Dropdown
label='Selecione...'
data={genderSelect}
baseColor={"white"}
textColor={"white"}
itemColor={"white"}
pickerStyle={{
backgroundColor: "black"
}}
onChangeText={(value) => {
this.setState({ gender : value })
console.log(this.gender)
}}
/>
<TouchableOpacity
style={styles.buttonContainer}
onPress= {()=>{
if (this.gender != undefined ) {
console.log(this.gender)
this.props.navigation.navigate("Abas")
}
else {
console.log(this.gender)
Alert.alert('Ops!','Favor preencher sua idade e gênero antes!');
}
}}
>
<Text style={styles.buttonText}>CONFIRMAR</Text>
</TouchableOpacity>
Btw, I suppose the problem ocurrs inside the onChangeText / setState section. No matter how I use 'if / else' afterwards, it keeps returning 'undefined'.
It’s probably a simple issue whose cause I didn’t get, I know. And I've searched a lot about it, but none of the answers actually helped me. Hope someone can help me.

Answer 1

Replace this.gender with this.state.gender
That's the error.. gender is a state variable so you have to access it like that.
In your return part change this
<TouchableOpacity
style={styles.buttonContainer}
onPress={() => {
if (this.state.gender != undefined) {
console.log(this.state.gender);
this.props.navigation.navigate('Abas');
} else {
console.log(this.state.gender);
Alert.alert('Ops!', 'Favor preencher sua idade e gênero antes!');
}
}}>
<Text style={styles.buttonText}>CONFIRMAR</Text>
</TouchableOpacity>