输入未显示

Question

我正在尝试制作一个计算器 如果我点击任何按钮进行输入... 没有输入... 触摸手势正常，表明已被触摸，但仍然没有输入... 我想念什么？

export default class App extends React.Component {      

    constructor(props) {
     super(props)
     this.initialState = {
          displayValue: '1'
     };
     this.state = this.initialState;
    }


 renderButtons = () => {

 let layouts = buttons.map((buttonRows, index) =>

 {
         let rowItem = buttonRows.map((buttonItems, buttonIndex) => {
         return <InputNumbers 
         value={buttonItems}
         handleOnPress = {this.handleInput.bind(this, buttonItems)}

key={'btn-' + buttonIndex} />
         });
      return <View style = {styles.inputRow} key={'row-' + index}>{rowItem}</View>
      }); 
      return layouts
     };    

     handleInput = (input) => {
       const { displayValue } = this.state;

       this.setState({
         displayValue: displayValue + input
       })
     }