Validation failure message for TextField in Grid not shown

Hi, 

I created a grid and added a header row to it. In the header row i added textfield for each column (to enable filtering of that column based on the text entered). Columns could be of Non String type (Numeric, Integer, Double, etc). I want that validation error is shown when a user enters a string inside the text field where  the column type is non string. 

I get InvalidValueException in the console, but nothign on the UI. 

for(Grid.Column col : grid.getColumns())
                {
                    com.vaadin.ui.Field field = beanFieldGroup.buildAndBind(null,col.getPropertyId());
                    if(TextField.class.isAssignableFrom(field.getClass()))
                    {
                        ((TextField)field).setNullRepresentation("");
                        ((TextField)field).setTextChangeEventMode(AbstractTextField.TextChangeEventMode.LAZY);
                        ((TextField)field).setImmediate(true);
                        ((TextField)field).setValidationVisible(true);
                        ((TextField)field).addTextChangeListener(new FieldEvents.TextChangeListener() {
                            @Override
                            public void textChange(FieldEvents.TextChangeEvent event) {
                                try {
                                    ((TextField)field).setValue(event.getText());

                                    // workaround cursor position problem
                                    ((TextField)field).setCursorPosition(event.getCursorPosition());

                                    ((TextField)field).validate();
                                    } catch (InvalidValueException e) {
                                        ((TextField)field).setComponentError(new SystemError(e));
                                    }
                            }
                        });
                    }
                    filteringHeader.getCell(col.getPropertyId()).setComponent(field);
                    
                }

If I am not wrong, I shouldn't even be writing the text listner. Since I have BeanFieldGroup, it should automatically create Validators for the text fields and trigger it. 

What am I doing wrong?

thanks for the help,
Chahat

Could it be because the fields are added to the cols of header row of a grid? Is it possible that Header row is not suppose to show validation errors??

Nope, I tested the code I published and it works. Did you remember to remove the TextChangeListener when trying with my aproach?

Hi Alejandro, 

I guess i did remove the TextChangeListner, I have a break point inside the validator, Now the break point is not even hit when i loose focus after entering a wrong value in the textfield. Below is my code 

T instance = clazz.getConstructor().newInstance();
                final BeanFieldGroup<T> beanFieldGroup = new BeanFieldGroup<T>(clazz);
                beanFieldGroup.setItemDataSource(instance);
                beanFieldGroup.setFieldFactory( new FieldGroupFieldFactory() {
                    
                    @Override
                    public <T extends com.vaadin.ui.Field> T createField(Class<?> dataType, Class<T> fieldType) {
                        T field = DefaultFieldGroupFieldFactory.get().createField(dataType, fieldType);
                        
                        if (Number.class.isAssignableFrom(dataType)) {
                            field.addValidator(value -> {
                                if (value != null && !value.toString().isEmpty() && !value.toString().matches("-?\\d+(\\.\\d+)?")) {
                                    throw new InvalidValueException("Please specify a number");
                                }
                            });
                        }

                        return field;
                    }
                });
                for(Grid.Column col : grid.getColumns())
                {
                    com.vaadin.ui.Field field = beanFieldGroup.buildAndBind(null,col.getPropertyId());
                    if(TextField.class.isAssignableFrom(field.getClass()))
                    {
                        ((TextField)field).setNullRepresentation("");
                        ((TextField)field).setTextChangeEventMode(AbstractTextField.TextChangeEventMode.LAZY);
                        ((TextField)field).setImmediate(true);
                        ((TextField)field).setValidationVisible(true);
                    }
                    filteringHeader.getCell(col.getPropertyId()).setComponent(field);
                    
                }

I could not create an instance of new DefaultFieldGroupFieldFactory() like you did. Probably different Vaadin versions, but I suppose what I did should have worked as well. 

Thanks for the help :)

thanks
Chahat

I'm using Vaadin 7.7.1. Here's the code that worked for me:

beanFieldGroup.setFieldFactory(new DefaultFieldGroupFieldFactory() {
    @Override
    public <T extends Field> T createField(Class<?> dataType, Class<T> fieldType) {
        T field = super.createField(dataType, fieldType);
        if (Number.class.isAssignableFrom(dataType)) {
            field.addValidator(value -> {
                if (value != null && !value.toString().isEmpty() && !value.toString().matches("-?\\d+(\\.\\d+)?")) {
                    throw new InvalidValueException("Please specify a number");
                }
            });
        }
        return field;
    }
});

for (Grid.Column col : grid.getColumns()) {
    Field<?> field = beanFieldGroup.buildAndBind(null, col.getPropertyId());
    filteringHeader.getCell(col.getPropertyId()).setComponent(field);
}

Hi there,
using vaadin 8.0.5 and the Grid row Editor in buffered mode,
bean is not updated when Validator fails, but Editor closes and I see no Error message ...
I expect it to stay open and tell me why validation fails.

final TextField nameEditor = new TextField();
final Binder<Site> binder = grid.getEditor().getBinder();
final Binder.Binding<Site, String> nameBinding = binder
    .withValidator( site -> {
        System.err.println("VALIDATE name");
        return site.getName().length() < 20;·
    }, "Name must be less than 20 characters long")
    .bind(nameEditor, Site::getName, Site::setName);
grid.addColumn(Site::getName)
    .setId("name")
    .setCaption("Site Name")
    .setEditorBinding(nameBinding);
grid.getEditor().setEnabled(true);
//grid.getEditor().setErrorGenerator((colMap, status) -> {
//    System.err.println("           Editor has errors : " + status.hasErrors());
//    return "Error String";
//});
grid.getEditor().getBinder().addStatusChangeListener( evt ->
    System.err.println("Status Change :" + evt. ▸  hasValidationErrors()));
grid.getEditor().addSaveListener( evt -> {
    System.err.println("SAVE");
    try { evt.getBean().save(); }
    catch(Exception e) { System.err.println(e.getMessage()); }
});

[java] VALIDATE name
[java] Status Change :true

thanks in advance ;)

Hi, in case you still have the issue. This is a possible implementation that works as expected:

Grid<Site> grid = new Grid<>();
grid.getEditor().setEnabled(true);
grid.getEditor().addSaveListener(t -> t.getBean().save());

TextField name = new TextField("Name");
Binder<Site> binder = grid.getEditor().getBinder();
Binder.Binding<Site, String> binding = binder.forField(name)
        .withValidator(new StringLengthValidator("Wrong length", 0, 19))
        .bind(Site::getName, Site::setName);

grid.addColumn(Site::getName).setEditorBinding(binding).setEditorComponent(name, Site::setName);

Hi, thanks for your attention, I've tested it and nailed the difference,

using forField(…) is the magic incantation, but then your validator deals with the value of the field

// works
final Binder.Binding<Site, String> binding =
    binder.forField(name)
    .withValidator(string -> string.length() > 6, "at least 6 chars")
    .bind(Site::getName, Site::setName);

as I would prefer to work with my object and simply use one of it's method, the following fails

// does not work
final Binder.Binding<Site, String> binding =
    binder
    .withValidator(obj -> obj.isValid(), "is not valid")
    .bind(name, Site::getName, Site::setName);

using setEditorComponent(…) or not doesn't change anything,
validation is not called at value change.

still .bind(name, Site::getName, Site::setName) calls forField(field).bind(getter, setter);
https://github.com/vaadin/framework/blob/master/server/src/main/java/com/vaadin/data/Binder.java#L1271

there is something fishy under there,
I'll try to investigate more later on.

Keep in mind that the buffered mode won't make the validations until you click "save".