Which are the correct constructors for JComboBox?
Which are the correct constructors for JComboBox?
Constructor of the JComboBox are:
- JComboBox() : creates a new empty JComboBox .
- JComboBox(ComboBoxModel M) : creates a new JComboBox with items from specified ComboBoxModel.
- JComboBox(E [ ] i) : creates a new JComboBox with items from specified array.
Which is the superclass for JComboBox?
The object of Choice class is used to show popup menu of choices. Choice selected by user is shown on the top of a menu. It inherits JComponent class.
Which JComboBox method makes the item at the specified index the selected item?
Method Summary
| Modifier and Type | Method and Description |
|---|---|
| ComboBoxEditor | getEditor() Returns the editor used to paint and edit the selected item in the JComboBox field. |
| E | getItemAt(int index) Returns the list item at the specified index. |
| int | getItemCount() Returns the number of items in the list. |
Which class encapsulates a combo box in Java?
Class JComboBox A component that combines a button or editable field and a drop-down list. The user can select a value from the drop-down list, which appears at the user’s request. If you make the combo box editable, then the combo box includes an editable field into which the user can type a value.
Which layout is used to arrange components in five regions?
Java BorderLayout
Java BorderLayout The BorderLayout is used to arrange the components in five regions: north, south, east, west, and center. Each region (area) may contain one component only. It is the default layout of a frame or window.
Which method is used to add items in Jcombobox?
To add a set of items to the combo box it is best to use the AddRange method. If you choose to use the Add method to add a number of items to the combo box, use the BeginUpdate method to suspend repainting during your add and the EndUpdate method to resume repainting.
Which method is used to add items in JComboBox?
Which method is used to register a mouse motion listener?
addMouseMotionListener method
The listener object created from that class is then registered with a component using the component’s addMouseMotionListener method. A mouse motion event is generated when the mouse is moved or dragged.
How to use javax.swing.jcombobox # setselecteditem ( )?
The following examples show how to use javax.swing.JComboBox #setSelectedItem () . These examples are extracted from open source projects. You can vote up the ones you like or vote down the ones you don’t like, and go to the original project or source file by following the links above each example.
What is the lightweightpopupenabled property in jcombobox?
Sets the lightWeightPopupEnabled property, which provides a hint as to whether or not a lightweight Component should be used to contain the JComboBox, versus a heavyweight Component such as a Panel or a Window. Sets the maximum number of rows the JComboBox displays.
How are itemlisteners added to a combo box?
For editable combo boxes, the selection will change to anObject. If this constitutes a change in the selected item, ItemListeners added to the combo box will be notified with one or two ItemEvents. If there is a current selected item, an ItemEvent will be fired and the state change will be ItemEvent.DESELECTED.
Which is the default data model in jcombobox?
Creates a JComboBox with a default data model. The default data model is an empty list of objects. Use addItem to add items. By default the first item in the data model becomes selected.