javaFX文本字段和侦听器

Question

I am facing a situation where there are two text fields with 2 seperate listeners for each of them.

TextField customerId and TextField customerName.

1000 mohan

1002 mithun

I am trying to automatically update other text field when one text field is filled eg if customerId 1000 is filled then corresponding customer name mohan get updated to text field customerName ,and if mohan is filled then his customer id 1000 will get filled in customerId text field.I am using maps,The problem is when one text field filled its listener is called which call backs the same text field listener and this causes cycles finally ending up with lot off errors.What should i do to solve this ?

Minimal example

    Map<String, String> treeMapCustomerName,treeMapCustomerId;

     treeMapCustomerName=new TreeMap<String,String>();
     treeMapCustomerId=new TreeMap<String,String>();
String customerName="mohan";
String customerId="1000";

treeMapCustomerId.put("1000","Mohan");
treeMapCustomerId.put("1002","Mithun");

treeMapCustomerName.put("Mohan","1000");
treeMapCustomerName.put("Mithun","1002");




        customerName.textProperty().addListener((observable, oldValue, newValue) -> {

        customerId.setText(treeMapCustomerName.get(customerName));//immediately customerId textfield listener is triggered which will trigger this listener causing cycles  

        });

        customerId.textProperty().addListener((observable, oldValue, newValue) -> {

        customerName.setText(treeMapCustomerId.get(customerId));

        });

Answer 1

You aren't taking advantage of your new values, instead you are accessing the map with the control, which will throw errors at run time

You could check if the map contains your key and only update the other text field if it is present, something like the below:

            customerName.textProperty().addListener((observable, oldValue, newValue) -> {
                if(treeMapCustomerName.containsKey(newValue)){
                    customerId.setText(treeMapCustomerName.get(newValue));
                }
            });

            customerId.textProperty().addListener((observable, oldValue, newValue) -> {
                if(treeMapCustomerId.containsKey(newValue)){
                    customerName.setText(treeMapCustomerId.get(newValue));
                }
            });

This will avoid issues with checking the map before a complete id / username has been entered, however this won't account for issues where a value being entered is a sub string of another.

Eg If the map contained id's 100, 1000, 10000 and you don't want each of these to display as the user types 10000, you may need an additional control such as a button instead of using the property