How can I create a custom field, that reveals a 2nd field if the 1st field is a certain value?

[Vincent Paladino]

Hello!

So what i'm currently working on is creating a dropdown search field that allows you to pick from a list of companies, then if the company you want it not listed, you can select 'new company' and then a text box will appear where you can fill in the new company. 

So far i've for a simple dropdown menu, and I'm trying to figure out how can i implement that new 2nd field to accompany the first. 

Here's my dropdown field as it is now:

```java

@Scanned
public class ClientField extends SelectCFType {


    private final OptionsManager optionsManager;

    protected ClientField(@JiraImport CustomFieldValuePersister customFieldValuePersister,
                          @JiraImport OptionsManager optionsManager,
                          @JiraImport GenericConfigManager genericConfigManager,
                          @JiraImport JiraBaseUrls jiraBaseUrls) {

        super(customFieldValuePersister, optionsManager, genericConfigManager, jiraBaseUrls);
        this.optionsManager = optionsManager;
    }

    @Override
    public Map<String, Object> getVelocityParameters(final Issue issue,
                                                     final CustomField field,
                                                     final FieldLayoutItem fieldLayoutItem) {

        final Map<String, Object> parameters = super.getVelocityParameters(issue, field, fieldLayoutItem);//
        FieldConfig fieldConfiguration = null;
        if(issue == null)
        {
            fieldConfiguration = field.getReleventConfig(new SearchContextImpl());
        } else
        {
            fieldConfiguration = field.getRelevantConfig(issue);
        }
        Options options = this.optionsManager.getOptions(fieldConfiguration);
        this.optionsManager.createOption(fieldConfiguration, null, new Long(1), "New Client");
        // TODO: Populate other options with 'Company names' from DB
        return parameters;
    }
}

```

Here is my edit.vm file so far. Basically just populating the dropdown with the options.

Also it checks if the dropdown equals 'New Client' and includes an additional `<input>` tag. This part does not work 

edit.vm:

```vm

#customControlHeader ($action $customField.id $customField.name $fieldLayoutItem.required $displayParameters $auiparams)

<select class="select" name="$customField.id" id="$customField.id">
#if (!$fieldLayoutItem || $fieldLayoutItem.required == false)
    <option value="-1">$i18n.getText("common.words.none")</option>
#else
    <option value="">$i18n.getText("common.words.none")</option>
#end
#foreach ($option in $configs.options)
    #if(!$option.disabled || $option.disabled == false || ($value && $value == $option.optionId.toString()))
    <option#if ($value && $value == $option.optionId.toString()) selected="selected"#end value="$option.optionId">$cfValueEncoder.encodeForHtml($option.value)</option>
    #end
#end
</select>

#if ($value.equals("New Client"))
<input type="text"
       name="$customField.id"
       value="$!value" />
#end

#customControlFooter ($action $customField.id $fieldLayoutItem.fieldDescription $displayParameters $auiparams)

```

For readaibility, i put these snippets in pastebin as well:

edit.vm

ClientField.java

Side question, is there a different field besides `SelectCFType` that lets the user search all the options? 

Any suggestions with how to approach this problem would be really appreciated. Thanks for your help!