InputDialog

A Dialog that asks for exactly one value: one label, one control, a save button and a cancel button. What comes back is the value, not the control.

Text2<String> title = new Text2<>(String.class);
title.setMandatory(true);
title.setValue("Big Ones");

InputDialog<String, Text2<String>> dlg = new InputDialog<>(title, "Rename the album", "New title") {
	@Override protected boolean onValidateData(String value) throws Exception {
		return value.length() >= 2;              // Refused: the dialog stays open
	}

	@Override protected boolean onSaveData(String value) throws Exception {
		album.setTitle(value);
		return true;
	}
};
add(dlg);

• The two type parameters
• What to override
• Confirming something

The two type parameters

InputDialog<T, C extends NodeBase & IControl<T>> - T is the type of the value being asked for and C the control that asks for it. Any control will do, since every one of them is an IControl<T>: a Text2<Integer> for a number, a ComboFixed2<Genre> for a choice, a DateInput2 for a date.

The buttons are made for you: unlike a bare Dialog, an InputDialog calls createButtons() itself and puts the bar at the bottom.

What to override

onValidate() and onSave() are final here: they read the control and hand the value to the two methods above, which is the whole point of the class. The value is read before validation, so both methods see the same thing; getInputControl() is there for the rare case where the control itself is needed.

Confirming something

Two ready-made dialogs use the same machinery to make an action hard to do by accident. Both are static methods returning a Dialog, which still has to be added to the page:

//-- The user has to type the name of the thing being deleted.
add(InputDialog.confirmDeleteInBlood("Delete \"Big Ones\"?", "Big Ones",
	"Type the album title to confirm", value -> {
		delete();
		return true;
	}));

//-- The user has to say why.
add(InputDialog.confirmWithReason("Cancel the order", 80, 40,
	"Cancel the order", Icon.faTimes, reason -> {
		cancel(reason);
		return true;
	}));

The handler is a predicate: returning false keeps the dialog open, exactly as onSaveData does.