Update Input Value while mapping React Native - react-native

Question

I am creating react-native mobile app. I have an array with some values. I want to set array's value into input field. I have added value in the fields but i can't able to update these values. I have set my values in a qty variable like this:
constructor(props) {
super(props);
this.state = {
qty:[],
}
}
componentWillMount() {
var ids = [];
this.props.data.map((dataImage,Index) => {
dataImage['pro-name'] != undefined && (
ids.push({'qty':dataImage['pro-qty']})
)
})
this.setState({qty:ids})
}
render() {
return {
this.props.data.map((dataImage,Index)=>(
<View key={Index} style={productStyle.cartview}>
{dataImage['pro-name'] && (
<View style={productStyle.cartmain}>
<Input value={this.state.qty[Index]['qty']} onChange={this.handleChangeInput.bind(this)} style={{width:40,height:40,textAlign:'left'}} />
</View>
)}
</View>
))
}
}
Its showing values properly into the input field but i can't able to type anything into the field to update the values. what can i do for this

Answer 1

I will suggest you to move your input container into separate class, its better approach and each component will handle its own state. Its easy to handle and will result better in performance too.
components = []
render() {
return this.props.data.map((item, index) => (
<CustomComponent data={item} index={index} ref={(ref) => this.components[index] = ref} />
))
}
You can then get child (CustomComponent) value from its ref.
this.components[index].getValue()
this.components[index].setValue('Value');
You will need to create these functions (getValue & setValue) in CustomComponent class.
solution
Here is solution to your query. You need to install lodash or find other solution to make a new copy qty.
<Input onChangeText={(text) => this.handleChangeText(text, index)} />
handleChangeText = (text, index) => {
const qty = _.cloneDeep(this.state.qty);
qty[index] = {
qty: text
}
this.setState({qty})
}

Answer 2

Your Input's value is set to this.state.qty[Index]['qty']. And to change it on text edit, you can do it like this. You do not need to bind the function, instead use an arrow function like this.
onChangeText={ (newValue) => {
this.setState({ <your-input-value-state>:newValue })
}}

Answer 3

You have to update the value of each Input individually on onChange event.
Replace your with Input with this
<Input value={this.state.qty[Index]['qty']}
onChange={this.handleChangeInput.bind(this, Index)}
style={{width:40,height:40,textAlign:'left'}}
/>
and update the state accordingly with the Index when the event is called
handleChangeInput(index, value){
let {qty} = this.state;
let qty_update = qty.slice();
qty_update[index]['qty'] = value;
this.setState({qty: qty_update});
}