valuePicker

<valuePicker id="valuePicker" dataContainer="customerDc" property="name" allowCustomValue="true"
             label="Name" helperText="Generate or type a customer name">
    <actions>
        <action id="generate" icon="REFRESH" description="Generate name"/>
        <action id="value_clear" type="value_clear"/>
    </actions>
</valuePicker>

@ViewComponent
protected InstanceContainer<Customer> customerDc;
@Autowired
protected Metadata metadata;

protected List<String> names = List.of("Katherine", "John", "Andy", "Edward", "George",
        "Philipp", "Dora", "James", "Daniel", "Michael", "Claire", "Joan", "Peter", "Martin");
@Subscribe
protected void onInit(InitEvent event) {
    Customer customer = metadata.create(Customer.class);
    customer.setName(getRandomName());
    customerDc.setItem(customer);
}
@Subscribe("valuePicker.generate")
protected void onValuePickerGenerateActionPerformed(ActionPerformedEvent event) {
    customerDc.getItem().setName(getRandomName());
}

@Subscribe("valuePicker")
protected void onValuePickerCustomValueChange(CustomValueSetEvent<JmixValuePicker<String>, String> event) {
    customerDc.getItem().setName(event.getText());
}

protected String getRandomName() {
    return names.get(RandomUtils.secure().randomInt() % names.size());
}

<data>
    <instance id="customerDc"
              class="io.jmix.uisamples.entity.Customer"
              fetchPlan="_local"/>
</data>
    <valuePicker id="valuePicker" dataContainer="customerDc" property="name" allowCustomValue="true"
                 label="Name" helperText="Generate or type a customer name">
        <actions>
            <action id="generate" icon="REFRESH" description="Generate name"/>
            <action id="value_clear" type="value_clear"/>
        </actions>
    </valuePicker>

<valuePicker id="valuePicker1" label="Random string">
    <actions>
        <action id="generate" icon="REFRESH" description="Generate value"/>
        <action id="value_clear" type="value_clear"/>
    </actions>
</valuePicker>

@ViewComponent
private JmixValuePicker<String> loginValuePicker;

@Autowired
private Actions actions;

@Subscribe
public void onInit(InitEvent event) {
    loginValuePicker.addAction(actions.create(ValueClearAction.ID));
}

<valuePicker id="valuePicker1" label="Random string">
    <actions>
        <action id="generate" icon="REFRESH" description="Generate value"/>
        <action id="value_clear" type="value_clear"/>
    </actions>
</valuePicker>

@ViewComponent
protected JmixValuePicker<String> valuePicker1;
@Subscribe("valuePicker1.generate")
protected void onValuePicker1GenerateActionPerformed(ActionPerformedEvent event) {
    generateValue(valuePicker1);
}
protected void generateValue(JmixValuePicker<String> valuePicker) {
    valuePicker.setValue(RandomStringUtils.secure().nextAlphabetic(5, 10));
}

@ViewComponent
protected JmixValuePicker<String> valuePicker2;
@Subscribe("valuePicker2")
protected void onValuePicker2CustomValueChange(CustomValueSetEvent<JmixValuePicker<String>, String> event) {
    event.getSource().setValue(event.getText());
}

@Install(to = "vPicker", subject = "formatter")
private String vPickerFormatter(String value) {
    return value != null ? "Code: " + value : null;
}