Package org.eclipse.swt.events

Class KeyEvent

  • All Implemented Interfaces:
    Serializable
    Direct Known Subclasses:
    TraverseEvent, VerifyEvent
    public class KeyEvent
extends TypedEvent
    Instances of this class are sent as a result of keys being pressed and released on the keyboard.

    When a key listener is added to a control, the control will take part in widget traversal. By default, all traversal keys (such as the tab key and so on) are delivered to the control. In order for a control to take part in traversal, it should listen for traversal events. Otherwise, the user can traverse into a control but not out. Note that native controls such as table and tree implement key traversal in the operating system. It is not necessary to add traversal listeners for these controls, unless you want to override the default traversal.

    See Also:
    KeyListener, TraverseListener, Sample code and further information, Serialized Form

    • Field Summary

      Fields 
      Modifier and Type Field Description
      char character
      the character represented by the key that was typed.
      boolean doit
      A flag indicating whether the operation should be allowed.
      int keyCode
      the key code of the key that was typed, as defined by the key code constants in class SWT.
      int keyLocation
      depending on the event, the location of key specified by the keyCode or character.
      int stateMask
      the state of the keyboard modifier keys and mouse masks at the time the event was generated.

    • Constructor Summary

      Constructors 
      Constructor Description
      KeyEvent​(Event e)
      Constructs a new instance of this class based on the information in the given untyped event.

    • Field Detail

      • character

        public char character
        the character represented by the key that was typed. This is the final character that results after all modifiers have been applied. For example, when the user types Ctrl+A, the character value is 0x01. It is important that applications do not attempt to modify the character value based on a stateMask (such as SWT.CTRL) or the resulting character will not be correct.

      • keyCode

        public int keyCode
        the key code of the key that was typed, as defined by the key code constants in class SWT. When the character field of the event is ambiguous, this field contains the unicode value of the original character. For example, typing Ctrl+M or Return both result in the character '\r' but the keyCode field will also contain '\r' when Return was typed.
        See Also:
        SWT

      • keyLocation

        public int keyLocation
        depending on the event, the location of key specified by the keyCode or character. The possible values for this field are SWT.LEFT, SWT.RIGHT, SWT.KEYPAD, or SWT.NONE representing the main keyboard area.

        The location field can be used to differentiate key events that have the same key code and character but are generated by different keys on the keyboard. For example, a key down event with the key code equal to SWT.SHIFT can be generated by the left and the right shift keys on the keyboard.

        The location field can only be used to determine the location of the key code or character in the current event. It does not include information about the location of modifiers in the state mask.

        Since:
        3.6
        See Also:
        SWT.LEFT, SWT.RIGHT, SWT.KEYPAD

      • stateMask

        public int stateMask
        the state of the keyboard modifier keys and mouse masks at the time the event was generated.
        See Also:
        SWT.MODIFIER_MASK, SWT.BUTTON_MASK

      • doit

        public boolean doit
        A flag indicating whether the operation should be allowed. Setting this field to false will cancel the operation.

    • Constructor Detail

      • KeyEvent

        public KeyEvent​(Event e)
        Constructs a new instance of this class based on the information in the given untyped event.
        Parameters:
        e - the untyped event containing the information

    • Method Detail

      • toString

        public String toString()
        Returns a string containing a concise, human-readable description of the receiver.
        Overrides:
        toString in class TypedEvent
        Returns:
        a string representation of the event