reactjs - React Native MobX FlatList extraData -


i cannot rows re-render when observable variable changes. can see console log triggering , managecart function indeed working. problem rows not update. have tried setting extradata on flatlist extradata={this.props.mainstore.productdatasource.slice()} or without . slice() still not help.

managecart(id, type) {     let tempone = this.props.mainstore.productdatasource.slice();     tempone.map((b, i) => {         if (b.product_id === id) {             b.qty = b.qty + 1;         }     });     this.props.mainstore.productdatasource = tempone; }      _renderrow = ({ item }) => {         return (             <productrow                 item={item}                 orientation={this.props.uistore.orientation}                 managecart={this.managecart}             />         )     }  render() {     console.log(this.props.mainstore.productdatasource.slice())     return (         <view style={styles.container}>             <statusbargray />             <fixedheader {...this.props} headerup={this.state.headerup} />             <flatlist                 onscroll={this.handlescroll.bind(this)}                 scrolleventthrottle={1}                 keyextractor={(_, i) => i}                 listheadercomponent={this._renderheader}                 data={this.props.mainstore.productdatasource.slice()}                 renderitem={this._renderrow}             />         </view>     ); }


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