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How to make only some columns editable in a Vaadin Grid?

Vaadin Grid allows to be defined as editable with
grid.setEditorEnabled(true);
This makes all visible columns editable. However I don't want the user to edit an specific column, but seems like the editable is an all or nothing.
The next best solution I have found is to define an editor field with a disabled editor, which almost does the trick but the user is still able to select the text and move the cursor (but the field is not editable anymore).
Grid.Column nameColumn = grid.getColumn("fullName");
nameColumn.setHeaderCaption("Full Name");
nameColumn.setEditorField(getNoEditableTextField());
...
private Field<?> getNoEditableTextField() {
TextField noEditableTextFiled = new TextField();
noEditableTextFiled.setEnabled(false);
return noEditableTextFiled;
}
I believe Label cannot be used because it's not a Field.
Is there a better option to achieve this?
edit: as aakath said, there is a way of achieving this not enabling the column to be edited, but in doing so the cell value disappears when you edit the row, which is not desirable.

Did you try calling setEditable(false) method on the column? I believe it should make the field non-editable when the item editor is active.
grid.getColumn("fullName").setEditable(false);

my solution is below. i have just finished. it was not tested too much. but it may give you some ideas.
ati
getColumn(columnName).setEditable(true).setEditorField(getNoEditableField(columnName));
...
private Field<?> getNoEditableField(final String columnName) {
CustomField<Label> result = new CustomField() {
#Override
protected Component getContent() {
Label result = (Label) super.getContent();
Object editedItemId = getEditedItemId();
String value = DEFAULT_VALUE;
if (editedItemId != null) {
value = CustomizableGrid.this.toString(getContainerDataSource().getItem(editedItemId).getItemProperty(columnName).getValue());
}
result.setValue(value);
return result;
}
#Override
protected Component initContent() {
Label result = new Label(DEFAULT_VALUE, ContentMode.HTML);
result.setDescription(getColumnDescription(columnName));
result.setStyleName("immutablegridcellstyle");
return result;
}
#Override
public Class getType() {
return Label.class;
}
};
result.setConverter(new Converter<Label, Object>() {
//converter for your data
});
return result;
}

I had the same problem and didn't want that clicking on id column opens editor. I solved it with adding an ItemClickListener as below. It works fine for me.
grid.addItemClickListener((ItemClickListener<GridBean>) event -> grid.getEditor().setEnabled(!event.getColumn().getCaption().equals("Id")));
Also byc clicking on specific columns Grid is not editable any more.

There is one tricky way to do it! I've just found out it.
So, first of all you need to use grid with container, instead of direct rows adding:
BeanItemContainer<MyBean> container = new BeanItemContainer<>(MyBean.class);
setContainerDataSource(container);
Then remove fields setters from MyBean, except setters for fields what you have to edit.

I think the same can be achieved by making the grid an editable one by grid.setEditorEnabled(true); and disabling editing option for other columns like grid.getColumn(columnName).setEditable(false);. But I am not sure of any demerits of this method. Any suggestion is always appreciated.

Its simple just go to Vaadin Documentation what did from it is below:
you can see here I gave a specified column Name
grid = new Grid<>();
lst = new ArrayList<>();
provider = new ListDataProvider<>(lst);
lst.add(new Company(1, "Java"));
grid.setDataProvider(provider);
grid.addColumn(Company::getSerialNo).setCaption("Sr.no");
TextField tf = new TextField();
grid.getEditor().setEnabled(true);
HorizontalLayout hlyt = new HorizontalLayout();
grid.addColumn(Company::getName).setEditorComponent(tf, Company::setName).setCaption("Name").setExpandRatio(2);
hlyt.addComponent(grid);

I use the following approach to get a read-only field, the trick is override the setEnabled method to get a disabled textfield. If you trace the source code in Vaadin Grid, no matter what field you pass to a Grid, it will always call the field.setEnabled(true).
myGrid.getColumn(propertyId).setEditorField(new ReadOnlyField());
And
public class ReadOnlyField extends TextField
{
public ReadOnlyField()
{
super();
this.setReadOnly(true);
}
#Override
public void setEnabled(boolean enabled)
{
// always set to disabled state
super.setEnabled(false);
}
}

Enable/Disable textbox using Checkbox in wicket framework

i would like to do Enable/Disable textbox using Checkbox in wicket framework.
here is my code:
List<DeliveryFormat> formatChoices = lookupProcessor.getLookupValues(DeliveryFormat.class);
//add(new RadioChoice("deliveryFormat", formatChoices, new ChoiceRenderer<DeliveryFormat>("label")));
//Add the check boxes for Delivery format
ChoiceRenderer<DeliveryFormat> deliveryFormatShippment = new ChoiceRenderer<DeliveryFormat>("label", "id");
CheckBoxMultipleChoice<DeliveryFormat> deliveryChoices = new CheckBoxMultipleChoice<DeliveryFormat>(
"deliveryFormat", formatChoices, deliveryFormatShippment);
add(deliveryChoices);
add(new DeliveryFormatValidator(deliveryChoices));
final WebMarkupContainer deliveryFormatCountryValue = new WebMarkupContainer("deliveryFormatCountry");
deliveryFormatCountryValue.setOutputMarkupId(true);
deliveryFormatCountryValue.setOutputMarkupPlaceholderTag(true);
add(deliveryFormatCountryValue);
deliveryFormatCountryValue.setVisible(DeliveryFormat.DELIVERY_FORMAT_ONE.equals(order.getObject().getDeliveryFormat()));
final TextArea<String> sampleTextArea = new TextArea<String>("address.country");
sampleTextArea.add(StringValidator.maximumLength(250)).add(
InlineErrorFeedback.INSTANCE);
sampleTextArea.setRequired(true);
sampleTextArea.setOutputMarkupId(true);
sampleTextArea.setMarkupId("address.country");
deliveryFormatCountryValue.add(sampleTextArea);
deliveryChoices.add(new AjaxFormComponentUpdatingBehavior("address.country") {
private static final long serialVersionUID = 1L;
#Override
protected void onUpdate(AjaxRequestTarget target) {
deliveryFormatCountryValue.setVisible(DeliveryFormat.DELIVERY_FORMAT_ONE.equals(order.getObject().getDeliveryFormat()));
target.addComponent(deliveryFormatCountryValue);
}
});
but i unable to do wt ever i want..is any thing wrong in my code?
my HTML page:
USA

The AjaxFormComponentUpdatingBehavior you are using expects the name of the JavaScript event you want to listen for and not the markup id of an HTML element, as you provided to it.
So for example new AjaxFormComponentUpdatingBehavior("change") would be correct.
In your case you could even use an OnChangeAjaxBehavior, since it's exactly made for the type of event you are trying to listen for.

You need to change this statement
deliveryChoices.add(new AjaxFormComponentUpdatingBehavior("address.country") {
to
deliveryChoices.add(new AjaxFormComponentUpdatingBehavior("onchange") {1

Updating a Wicket WebMarkupContainer

Inside my Wicket webpage, I have a WebMarkupContainer which contains a ListView:
notifications = new ArrayList<Notification>(...);
ListView listView = new ListView("notification", notifications) {
#Override
protected void populateItem(ListItem item) {
...
}
};
container = new WebMarkupContainer("container");
container.setOutputMarkupId(true);
container.add(listView);
this.add(container);
The WebMarkupContainer is in place in order to let me dynamically update the list of items shown to the user onscreen. This is possible when the user clicks on a link or by adding the container to incoming AjaxRequestTarget.
Now I'm required to update the list without having an Ajax request:
public void refresh() {
List<Notification> newNotifications = ...
notifications.addAll(0, newNotifications);
}
This method is called in a run-time environment and the list of notifications, which is a private field of my webpage (same one as last code), will contain new objects. I want these new items displayed to the user. Is it possible to update (or re-render) the container?
I'm new to Wicket so if you have a better way to achieve the same results, I would appreciate if you could share it with me.

You would have to do it on a timer. Use AjaxSelfUpdatingTimerBehavior to do so. Just set some sensible duration and add your container to target in 'onTimer()' method.
EDIT:
If your 'refresh()' function is only called when new notifications appear, you could set a flag on your page (define boolean variable on page and change it to true when new notification appears and to false once listView is refreshed). Then you can set short duration on the behavior and 'onTimer()' would look something like that:
onTimer(AjaxRequestTarget target) {
if(newNotifications) {
target.add(container);
newNotifications = false;
}
}
And refresh
public void refresh() {
List<Notification> newNotifications = ...
notifications.addAll(0, newNotifications);
newNotifiactions = true;
}
That way container won't be refreshed too often (which might cause strange effects) and will refresh every time new notification appears.

JavaFX TextArea and autoscroll

I am trying to get a TextArea to autoscroll to the bottom with new text which is put in via an event handler. Each new entry is just one long string of text with each entry separated by a line break. I have tried a change handler which sets setscrolltop to Double.MIN_VALUE but to no avail. Any ideas of how this could be done?

You have to add a listener to the TextArea element to scroll to the bottom when it's value is changed:
#FXML private TextArea txa;
...
txa.textProperty().addListener(new ChangeListener<Object>() {
#Override
public void changed(ObservableValue<?> observable, Object oldValue,
Object newValue) {
txa.setScrollTop(Double.MAX_VALUE); //this will scroll to the bottom
//use Double.MIN_VALUE to scroll to the top
}
});
But this listener is not triggered when you use the setText(text) method, so if you want to trigger it after a setText(text) use the appendText(text) right after it:
txa.setText("Text into the textArea"); //does not trigger the listener
txa.appendText(""); //this will trigger the listener and will scroll the
//TextArea to the bottom
This sounds more like a bug, once the setText() should trigger the changed listener, however it doesn't. This is the workaround I use myself and hope it helps you.

txa.appendText("") will scroll to the bottom without a listener. This becomes an issue if you want to scroll back and the text is being constantly updated. txa.setText("") puts the scroll bar back at the top and same issue applies.
My solution was to extend the TextArea class, ammend the FXML tag from textArea to LogTextArea. Where this works, it clearly causes problems in scene builder as it does not know what this component is
import javafx.scene.control.TextArea;
import javafx.scene.text.Font;
public class LogTextArea extends TextArea {
private boolean pausedScroll = false;
private double scrollPosition = 0;
public LogTextArea() {
super();
}
public void setMessage(String data) {
if (pausedScroll) {
scrollPosition = this.getScrollTop();
this.setText(data);
this.setScrollTop(scrollPosition);
} else {
this.setText(data);
this.setScrollTop(Double.MAX_VALUE);
}
}
public void pauseScroll(Boolean pause) {
pausedScroll = pause;
}
}

I don't have enough reputation to comment, but wanted to give some insight for future readers as to why setText doesn't appear to trigger the listener, but appendText does, as in Math's answer.
I Just found this answer while encountering similar issues myself, and looked into the code. This is currently the top result for 'javafx textarea settext scroll' in a google search.
setText does indeed trigger the listener.
According to the javadoc on the doSet method in TextInputControl (TextArea's superclass):
* doSet is called whenever the setText() method was called directly
* on the TextInputControl, or when the text property was bound,
* unbound, or reacted to a binding invalidation. It is *not* called
* when modifications to the content happened indirectly, such as
* through the replaceText / replaceSelection methods.
Inside the doSet method, a call is made to updateText(), which TextArea overrides:
#Override final void textUpdated() {
setScrollTop(0);
setScrollLeft(0);
}
So, when you set the scroll amount in the listener as in Math's answer, the following happens:
The TextProperty is updated
Your listener is called, and the scroll is set
doSet is called
textUpdated is called
The scroll is set back to the top-left
When you then append "",
The TextProperty is updated
Your listener is called, and the scroll is set
The javadoc is above is clear why this is the case - doSet is only called when using setText.
In fact, appendText calls insertText which calls replaceText - and the javadoc further states that replaceText does NOT trigger a call to doSet.
The behaviour is rather irritating, especially since these are all final methods, and not obvious at first glance - but is not a bug.

Alternative to that strange setText bug without using appendText
textArea.selectPositionCaret(textArea.getLength());
textArea.deselect(); //removes the highlighting

One addendum I would add to jamesarbrown's response would be to this would be to use a boolean property instead so you can access it from within FXML.
Something like this.
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.SimpleBooleanProperty;
import javafx.scene.control.TextArea;
public class LogTextArea extends TextArea {
private final BooleanProperty pausedScrollProperty = new SimpleBooleanProperty(false);
private double scrollPosition = 0;
public LogTextArea() {
super();
}
public void setMessage(String data) {
if (isPausedScroll()) {
scrollPosition = this.getScrollTop();
this.setText(data);
this.setScrollTop(scrollPosition);
} else {
this.setText(data);
this.setScrollTop(Double.MAX_VALUE);
}
}
public final BooleanProperty pausedScrollProperty() { return pausedScrollProperty; }
public final boolean isPausedScroll() { return pausedScrollProperty.getValue(); }
public final void setPausedScroll(boolean value) { pausedScrollProperty.setValue(value); }
}
However, the problem with this answer is that if you get flooded with an unreasonably large amount of input (as can happen when retrieving a log from an IO Stream) the javaFX thread will lock up because the TextArea gets too much data.

As Matthew has posted the setText call is the problem. A easy workaround is to call clear, appendText and then setScrollTop. The other suggestions above did not work well for me, with enough delay it worked but was unreliable behaviour.
textAreaListener = (observable, oldValue, newValue) -> {
textArea.clear();
textArea.appendText(newValue);
textArea.setScrollTop(Double.MAX_VALUE);
};

In Model-View-Controller, Why change in model, doesn't trigger the change in view?

I am currently developing my own minesweeper. Swing follows Model-View-Controller design pattern. In MVC, I learnt whenever there is a change in model, the controller will trigger that change in view too. But In this example, I cannot trace how to make the changes in setTitle and setInfo to get reflected in view.
Here, when I set the title of the Dialog box, the actual content(model) is getting changed, But there is no corresponding change in the output(view).
//InfoDisplayer is inner class of class MenuActionListener
class InfoDisplayer extends JDialog {
JLabel info;
BorderLayout infoBorderLayout = new BorderLayout();
public InfoDisplayer(JFrame ownerFrame) {
super(ownerFrame,true);
info = new JLabel();
setFocusable(false);
setSize(300,400);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setLayout(infoBorderLayout);
add(info,BorderLayout.SOUTH);
setVisible(true);
}
void setInfo(JLabel info) {
this.info = info;
}
public void setTitle(String title) {
super.setTitle(title);
}
}
if ((event.getActionCommand()).equals("HowToPlay")) {
InfoDisplayer instructionsDisplay = new InfoDisplayer(gUIManagerFrame);
//gUIManagerFrame is an object of its outer class,MenuActionListener
instructionsDisplay.setTitle("INSTRUCTIONS");
instructionsDisplay.setInfo(new JLabel("<html><h1><B>INSTRUCTIONS</B></h1></html>"));
} else {// if about is clicked!!
InfoDisplayer aboutDisplay = new InfoDisplayer(gUIManagerFrame);
aboutDisplay.setTitle("MineSweeper v0.1");
aboutDisplay.setInfo(new JLabel("<html><h1><B>MineSweeperv1.0</B></h1> </html>"));
}

Whenever there is a change in model, the controller will trigger that change in view.
In the Model–View–Controller pattern, when the controller updates the model, the model will notify the view, typically using the observer pattern, and the view then updates itself. The view may interrogate the model and process any resulting update. There's a more detailed answer and example here.

You will need to remove the old jlabel and add the new one to the frame.
Though it would make more sense probably to set the text on the existing label rather than a whole new label.

Swing indeed has a model and a view side. For example in a JTable the JTable is the view and the TableModel is the model. When you construct a JTable, you need to pass it a model either during construction or by using the setter. The JTable will then add a listener to model to get informed about any model changes. You can see this listener as the controller.
However, this does not mean that when you use an arbitrary combination of Swing classes they will auto-magically get informed about each other changes. In your case, the label is certainly not 'the model' of your dialog, and there is no such thing as a 'controller' between your label and the dialog. When you make such a change, you need to inform the dialog yourself (and probably add the label to your dialog as well).
Oh, and I would recommend changing your setTitle method into
public void setTitle( String aTitle ){
super.setTitle( aTittle );
}
or remove it completely. This will avoid a StackOverflowException