# Class TrayIcon

java.lang.Object
java.awt.TrayIcon

public class TrayIcon extends Object
A `TrayIcon` object represents a tray icon that can be added to the `system tray`. A `TrayIcon` can have a tooltip (text), an image, a popup menu, and a set of listeners associated with it.

A `TrayIcon` can generate various `MouseEvents` and supports adding corresponding listeners to receive notification of these events. `TrayIcon` processes some of the events by itself. For example, by default, when the right-mouse click is performed on the `TrayIcon` it displays the specified popup menu. When the mouse hovers over the `TrayIcon` the tooltip is displayed (this behaviour is platform dependent).

Note: When the `MouseEvent` is dispatched to its registered listeners its `component` property will be set to `null`. (See `ComponentEvent.getComponent()`) The `source` property will be set to this `TrayIcon`. (See `EventObject.getSource()`)

Note: A well-behaved `TrayIcon` implementation will assign different gestures to showing a popup menu and selecting a tray icon.

A `TrayIcon` can generate an `ActionEvent`. On some platforms, this occurs when the user selects the tray icon using either the mouse or keyboard.

See the `SystemTray` class overview for an example on how to use the `TrayIcon` API.

Implementation Note:
  When the `apple.awt.enableTemplateImages` property is set, all images associated with instances of this class are treated as template images by the native desktop system. This means all color information is discarded, and the image is adapted automatically to be visible when desktop theme and/or colors change. This property only affects MacOSX.
Since:
  1.6
See Also:
  - `SystemTray.add(TrayIcon)`
  - `ComponentEvent.getComponent()`
  - `EventObject.getSource()`

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static enum`
  `TrayIcon.MessageType`
  The message type determines which icon will be displayed in the caption of the message, and a possible system sound a message may generate upon showing.

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `TrayIcon(Image image)`
  Creates a `TrayIcon` with the specified image.
  `TrayIcon(Image image, String tooltip)`
  Creates a `TrayIcon` with the specified image and tooltip text.
  `TrayIcon(Image image, String tooltip, PopupMenu popup)`
  Creates a `TrayIcon` with the specified image, tooltip and popup menu.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `addActionListener(ActionListener listener)`
  Adds the specified action listener to receive `ActionEvent`s from this `TrayIcon`.
  `void`
  `addMouseListener(MouseListener listener)`
  Adds the specified mouse listener to receive mouse events from this `TrayIcon`.
  `void`
  `addMouseMotionListener(MouseMotionListener listener)`
  Adds the specified mouse listener to receive mouse-motion events from this `TrayIcon`.
  `void`
  `displayMessage(String caption, String text, TrayIcon.MessageType messageType)`
  Displays a popup message near the tray icon.
  `String`
  `getActionCommand()`
  Returns the command name of the action event fired by this tray icon.
  `ActionListener[]`
  `getActionListeners()`
  Returns an array of all the action listeners registered on this `TrayIcon`.
  `Image`
  `getImage()`
  Returns the current image used for this `TrayIcon`.
  `MouseListener[]`
  `getMouseListeners()`
  Returns an array of all the mouse listeners registered on this `TrayIcon`.
  `MouseMotionListener[]`
  `getMouseMotionListeners()`
  Returns an array of all the mouse-motion listeners registered on this `TrayIcon`.
  `PopupMenu`
  `getPopupMenu()`
  Returns the popup menu associated with this `TrayIcon`.
  `Dimension`
  `getSize()`
  Returns the size, in pixels, of the space that the tray icon occupies in the system tray.
  `String`
  `getToolTip()`
  Returns the tooltip string associated with this `TrayIcon`.
  `boolean`
  `isImageAutoSize()`
  Returns the value of the auto-size property.
  `void`
  `removeActionListener(ActionListener listener)`
  Removes the specified action listener.
  `void`
  `removeMouseListener(MouseListener listener)`
  Removes the specified mouse listener.
  `void`
  `removeMouseMotionListener(MouseMotionListener listener)`
  Removes the specified mouse-motion listener.
  `void`
  `setActionCommand(String command)`
  Sets the command name for the action event fired by this tray icon.
  `void`
  `setImage(Image image)`
  Sets the image for this `TrayIcon`.
  `void`
  `setImageAutoSize(boolean autosize)`
  Sets the auto-size property.
  `void`
  `setPopupMenu(PopupMenu popup)`
  Sets the popup menu for this `TrayIcon`.
  `void`
  `setToolTip(String tooltip)`
  Sets the tooltip string for this `TrayIcon`.

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Constructor Details

  - ### TrayIcon

    public TrayIcon(Image image)
    Creates a `TrayIcon` with the specified image.
    Parameters:
      `image` - the `Image` to be used
    Throws:
      `IllegalArgumentException` - if `image` is `null`
      `UnsupportedOperationException` - if the system tray isn't supported by the current platform
      `HeadlessException` - if `GraphicsEnvironment.isHeadless()` returns `true`
    See Also:
      - `SystemTray.add(TrayIcon)`
      - `TrayIcon(Image, String, PopupMenu)`
      - `TrayIcon(Image, String)`

  - ### TrayIcon

    public TrayIcon(Image image, String tooltip)
    Creates a `TrayIcon` with the specified image and tooltip text. Tooltip may be not visible on some platforms.
    Parameters:
      `image` - the `Image` to be used
      `tooltip` - the string to be used as tooltip text; if the value is `null` no tooltip is shown
    Throws:
      `IllegalArgumentException` - if `image` is `null`
      `UnsupportedOperationException` - if the system tray isn't supported by the current platform
      `HeadlessException` - if `GraphicsEnvironment.isHeadless()` returns `true`
    See Also:
      - `SystemTray.add(TrayIcon)`
      - `TrayIcon(Image)`
      - `TrayIcon(Image, String, PopupMenu)`

  - ### TrayIcon

    public TrayIcon(Image image, String tooltip, PopupMenu popup)
    Creates a `TrayIcon` with the specified image, tooltip and popup menu. Tooltip may be not visible on some platforms.
    Parameters:
      `image` - the `Image` to be used
      `tooltip` - the string to be used as tooltip text; if the value is `null` no tooltip is shown
      `popup` - the menu to be used for the tray icon's popup menu; if the value is `null` no popup menu is shown
    Throws:
      `IllegalArgumentException` - if `image` is `null`
      `UnsupportedOperationException` - if the system tray isn't supported by the current platform
      `HeadlessException` - if `GraphicsEnvironment.isHeadless()` returns `true`
    See Also:
      - `SystemTray.add(TrayIcon)`
      - `TrayIcon(Image, String)`
      - `TrayIcon(Image)`
      - `PopupMenu`
      - `MouseListener`
      - `addMouseListener(MouseListener)`

- ## Method Details

  - ### setImage

    public void setImage(Image image)
    Sets the image for this `TrayIcon`. The previous tray icon image is discarded without calling the `Image.flush()` method — you will need to call it manually.

    If the image represents an animated image, it will be animated automatically.

    See the `setImageAutoSize(boolean)` property for details on the size of the displayed image.

    Calling this method with the same image that is currently being used has no effect.

    Parameters:
      `image` - the non-null `Image` to be used
    Throws:
      `NullPointerException` - if `image` is `null`
    See Also:
      - `getImage()`
      - `Image`
      - `SystemTray.add(TrayIcon)`
      - `TrayIcon(Image, String)`

  - ### getImage

    public Image getImage()
    Returns the current image used for this `TrayIcon`.
    Returns:
      the image
    See Also:
      - `setImage(Image)`
      - `Image`

  - ### setPopupMenu

    public void setPopupMenu(PopupMenu popup)
    Sets the popup menu for this `TrayIcon`. If `popup` is `null`, no popup menu will be associated with this `TrayIcon`.

    Note that this `popup` must not be added to any parent before or after it is set on the tray icon. If you add it to some parent, the `popup` may be removed from that parent.

    The `popup` can be set on one `TrayIcon` only. Setting the same popup on multiple `TrayIcon`s will cause an `IllegalArgumentException`.

    Note: Some platforms may not support showing the user-specified popup menu component when the user right-clicks the tray icon. In this situation, either no menu will be displayed or, on some systems, a native version of the menu may be displayed.

    Parameters:
      `popup` - a `PopupMenu` or `null` to remove any popup menu
    Throws:
      `IllegalArgumentException` - if the `popup` is already set for another `TrayIcon`
    See Also:
      - `getPopupMenu()`

  - ### getPopupMenu

    public PopupMenu getPopupMenu()
    Returns the popup menu associated with this `TrayIcon`.
    Returns:
      the popup menu or `null` if none exists
    See Also:
      - `setPopupMenu(PopupMenu)`

  - ### setToolTip

    public void setToolTip(String tooltip)
    Sets the tooltip string for this `TrayIcon`. The tooltip is displayed automatically when the mouse hovers over the icon. Tooltip may be not visible on some platforms. Setting the tooltip to `null` removes any tooltip text. When displayed, the tooltip string may be truncated on some platforms; the number of characters that may be displayed is platform-dependent.
    Parameters:
      `tooltip` - the string for the tooltip; if the value is `null` no tooltip is shown
    See Also:
      - `getToolTip()`

  - ### getToolTip

    public String getToolTip()
    Returns the tooltip string associated with this `TrayIcon`.
    Returns:
      the tooltip string or `null` if none exists
    See Also:
      - `setToolTip(String)`

  - ### setImageAutoSize

    public void setImageAutoSize(boolean autosize)
    Sets the auto-size property. Auto-size determines whether the tray image is automatically sized to fit the space allocated for the image on the tray. By default, the auto-size property is set to `false`.

    If auto-size is `false`, and the image size doesn't match the tray icon space, the image is painted as-is inside that space — if larger than the allocated space, it will be cropped.

    If auto-size is `true`, the image is stretched or shrunk to fit the tray icon space.

    Parameters:
      `autosize` - `true` to auto-size the image, `false` otherwise
    See Also:
      - `isImageAutoSize()`

  - ### isImageAutoSize

    public boolean isImageAutoSize()
    Returns the value of the auto-size property.
    Returns:
      `true` if the image will be auto-sized, `false` otherwise
    See Also:
      - `setImageAutoSize(boolean)`

  - ### addMouseListener

    public void addMouseListener(MouseListener listener)
    Adds the specified mouse listener to receive mouse events from this `TrayIcon`. Calling this method with a `null` value has no effect.

    Note: The `MouseEvent`'s coordinates (received from the `TrayIcon`) are relative to the screen, not the `TrayIcon`.

    Note: The `MOUSE_ENTERED` and `MOUSE_EXITED` mouse events are not supported.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the mouse listener
    See Also:
      - `MouseEvent`
      - `MouseListener`
      - `removeMouseListener(MouseListener)`
      - `getMouseListeners()`

  - ### removeMouseListener

    public void removeMouseListener(MouseListener listener)
    Removes the specified mouse listener. Calling this method with `null` or an invalid value has no effect.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the mouse listener
    See Also:
      - `MouseEvent`
      - `MouseListener`
      - `addMouseListener(MouseListener)`
      - `getMouseListeners()`

  - ### getMouseListeners

    public MouseListener[] getMouseListeners()
    Returns an array of all the mouse listeners registered on this `TrayIcon`.
    Returns:
      all of the `MouseListeners` registered on this `TrayIcon` or an empty array if no mouse listeners are currently registered
    See Also:
      - `addMouseListener(MouseListener)`
      - `removeMouseListener(MouseListener)`
      - `MouseListener`

  - ### addMouseMotionListener

    public void addMouseMotionListener(MouseMotionListener listener)
    Adds the specified mouse listener to receive mouse-motion events from this `TrayIcon`. Calling this method with a `null` value has no effect.

    Note: The `MouseEvent`'s coordinates (received from the `TrayIcon`) are relative to the screen, not the `TrayIcon`.

    Note: The `MOUSE_DRAGGED` mouse event is not supported.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the mouse listener
    See Also:
      - `MouseEvent`
      - `MouseMotionListener`
      - `removeMouseMotionListener(MouseMotionListener)`
      - `getMouseMotionListeners()`

  - ### removeMouseMotionListener

    public void removeMouseMotionListener(MouseMotionListener listener)
    Removes the specified mouse-motion listener. Calling this method with `null` or an invalid value has no effect.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the mouse listener
    See Also:
      - `MouseEvent`
      - `MouseMotionListener`
      - `addMouseMotionListener(MouseMotionListener)`
      - `getMouseMotionListeners()`

  - ### getMouseMotionListeners

    public MouseMotionListener[] getMouseMotionListeners()
    Returns an array of all the mouse-motion listeners registered on this `TrayIcon`.
    Returns:
      all of the `MouseInputListeners` registered on this `TrayIcon` or an empty array if no mouse listeners are currently registered
    See Also:
      - `addMouseMotionListener(MouseMotionListener)`
      - `removeMouseMotionListener(MouseMotionListener)`
      - `MouseMotionListener`

  - ### getActionCommand

    public String getActionCommand()
    Returns the command name of the action event fired by this tray icon.
    Returns:
      the action command name, or `null` if none exists
    See Also:
      - `addActionListener(ActionListener)`
      - `setActionCommand(String)`

  - ### setActionCommand

    public void setActionCommand(String command)
    Sets the command name for the action event fired by this tray icon. By default, this action command is set to `null`.
    Parameters:
      `command` - a string used to set the tray icon's action command.
    See Also:
      - `ActionEvent`
      - `addActionListener(ActionListener)`
      - `getActionCommand()`

  - ### addActionListener

    public void addActionListener(ActionListener listener)
    Adds the specified action listener to receive `ActionEvent`s from this `TrayIcon`. Action events usually occur when a user selects the tray icon, using either the mouse or keyboard. The conditions in which action events are generated are platform-dependent.

    Calling this method with a `null` value has no effect.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the action listener
    See Also:
      - `removeActionListener(ActionListener)`
      - `getActionListeners()`
      - `ActionListener`
      - `setActionCommand(String)`

  - ### removeActionListener

    public void removeActionListener(ActionListener listener)
    Removes the specified action listener. Calling this method with `null` or an invalid value has no effect.

    Refer to AWT Threading Issues for details on AWT's threading model.

    Parameters:
      `listener` - the action listener
    See Also:
      - `ActionEvent`
      - `ActionListener`
      - `addActionListener(ActionListener)`
      - `getActionListeners()`
      - `setActionCommand(String)`

  - ### getActionListeners

    public ActionListener[] getActionListeners()
    Returns an array of all the action listeners registered on this `TrayIcon`.
    Returns:
      all of the `ActionListeners` registered on this `TrayIcon` or an empty array if no action listeners are currently registered
    See Also:
      - `addActionListener(ActionListener)`
      - `removeActionListener(ActionListener)`
      - `ActionListener`

  - ### displayMessage

    public void displayMessage(String caption, String text, TrayIcon.MessageType messageType)
    Displays a popup message near the tray icon. The message will disappear after a time or if the user clicks on it. Clicking on the message may trigger an `ActionEvent`.

    Either the caption or the text may be `null`, but an `NullPointerException` is thrown if both are `null`. When displayed, the caption or text strings may be truncated on some platforms; the number of characters that may be displayed is platform-dependent.

    Note: Some platforms may not support showing a message.

    Parameters:
      `caption` - the caption displayed above the text, usually in bold; may be `null`
      `text` - the text displayed for the particular message; may be `null`
      `messageType` - an enum indicating the message type
    Throws:
      `NullPointerException` - if both `caption` and `text` are `null`

  - ### getSize

    public Dimension getSize()
    Returns the size, in pixels, of the space that the tray icon occupies in the system tray. For the tray icon that is not yet added to the system tray, the returned size is equal to the result of the `SystemTray.getTrayIconSize()`.
    Returns:
      the size of the tray icon, in pixels
    See Also:
      - `setImageAutoSize(boolean)`
      - `Image`
      - `getSize()`