What is the JComboBox?
JComboBox is a part of Java Swing package. JComboBox inherits JComponent class . JComboBox shows a popup menu that shows a list and the user can select a option from that specified list . JComboBox can be editable or read- only depending on the choice of the programmer .
What is getSelectedIndex?
getSelectedIndex() Returns the first item in the list that matches the given item. Object. getSelectedItem() Returns the current selected item.
How do I resize a comboBox in Java?
setMaximumSize( comboBox. getPreferredSize() ); Or you can do something like: JPanel wrapper = new JPanel(); wrapper.
What event does JComboBox generate?
A JButton object draws itself and processes mouse, keyboard, and focus events on its own. You only hear from the JButton when the user triggers it by clicking on it or pressing the space bar while the button has the input focus. When this happens, the JButton object creates an event object belonging to the class java.
Which listener is applied on a JComboBox?
It is used to add the ActionListener. It is used to add the ItemListener.
What is the difference between a combo box and a list box?
List box is used to list the number of items in a specific manner and provides a facility to select one of the field from the list only using drop down list. In combo box you can select one of the required field from the list by typing in the box or by using drop down list.
What is a JScrollPane?
A JScrollPane provides a scrollable view of a component. When screen real estate is limited, use a scroll pane to display a component that is large or one whose size can change dynamically. The boldface line of code creates the JScrollPane , specifying the text area as the scroll pane’s client.
What is JLabel Java Swing?
JLabel is a class of java Swing . JLabel is used to display a short string or an image icon. JLabel can display text, image or both . JLabel is only a display of text or image and it cannot get focus . JLabel is inactive to input events such a mouse focus or keyboard focus.
What is difference between swing and AWT?
The main difference between AWT and Swing in Java is that the AWT is Java’s original platform-dependent windowing, graphics, and user interface widget toolkit while the Swing is a GUI widget toolkit for Java that is an extension of AWT. It provides toolkits to build rich Graphical User Interfaces (GUI).
What is difference between Swing and AWT?
Which method is used to add items to Jcombobox?
Commonly used Methods:
| Methods | Description |
|---|---|
| void addItem(Object anObject) | It is used to add an item to the item list. |
| void removeItem(Object anObject) | It is used to delete an item to the item list. |
| void removeAllItems() | It is used to remove all the items from the list. |
What is list box example?
A list box is a graphical control element that allows the user to select one or more items from a list contained within a static, multiple line text box. The user clicks inside the box on an item to select it, sometimes in combination with the ⇧ Shift or Ctrl in order to make multiple selections.
What happens when you change the selection in a jcombobox?
Whenever you change the selection in a JComboBox, the itemStateChanged event is triggered twice, once for DESELECT of the old selected item and once for SELECT for the new selected item. if (e.getStateChange () == ItemEvent.SELECTED) {
What is the difference between count and set in jcombobox?
Sets the maximum number of rows the JComboBox displays. If the number of objects in the model is greater than count, the combo box uses a scrollbar. count – an integer specifying the maximum number of items to display in the list before using a scrollbar
What is setmodel and setpopupvisible in jcombobox?
setModel(ComboBoxModel aModel) Sets the data model that the JComboBox uses to obtain the list of items. setPopupVisible(boolean v) Sets the visibility of the popup. setPrototypeDisplayValue(E prototypeDisplayValue) Sets the prototype display value used to calculate the size of the display for the UI portion.
What is an editable jcombobox?
An editable JComboBox allows the user to type into the field or selected an item from the list to initialize the field, after which it can be edited. (The editing affects only the field, the list item remains intact.)