Question

我正在ios上开发本机应用程序。我想对导航标题后退按钮单击做一些自定义逻辑。我的router.js代码是：

export const ProjectStack = createStackNavigator({

Question:{
screen: Question,

     navigationOptions: {
  title: 'Frage',
  headerLeft: <HeaderBackButton  onPress={() => navigationOptions.state.handleSave()} />

},
  },
});

在组件中，我正在这样做：

componentDidMount(){

  this.props.navigation.setParams({ handleSave: this._saveDetails });
}

_saveDetails() {
  console.log("Back Button Clicked");
  }

当组件加载时，出现异常：

Invariant violation: setParams can not be called by root navigator

有什么问题，我找不到问题

Answer 1

您只能从导航器的屏幕组件之一修改其导航选项。这同样适用于嵌套为屏幕的导航器。（Documentation link）

正确的方法是

在组件中设置导航选项

class Filters extends React.Component {

 static navigationOptions = ({ navigation }) => {
    const handleSave = navigation.getParam("handleSave", () => {});
    return {
      title: 'Frage',
      headerLeft: <HeaderBackButton onPress={handleSave} />
    };
  };

并在组件的componentDidMount中设置

componentDidMount(){

  this.props.navigation.setParams({ handleSave: this._saveDetails });
}

_saveDetails = () => {
  console.log("Back Button Clicked");
  }

root导航器无法调用setParams

1 个答案: