An action which can be triggered by a menu or toolbar item.
Actions represent operations that the user can be perform, along with some
information how it should be presented in the interface. Each action provides
methods to create icons, menu items and toolbar items representing itself.
As well as the callback that is called when the action gets activated, the
following also gets associated with the action:
a name (not translated, for path lookup)
a label (translated, for display)
an accelerator
whether label indicates a stock id
a tooltip (optional, translated)
a toolbar label (optional, shorter than label)
The action will also have some state information:
visible (shown/hidden)
sensitive (enabled/disabled)
Apart from regular actions, there are
ToggleAction
, which can be
toggled between two states and
RadioAction
, of which only one in a
group can be in the "active" state. Other actions can be implemented as
Action
subclasses.
Each action can have one or more proxy menu item, toolbar button or other
proxy widgets. Proxies mirror the state of the action (text label, tooltip,
icon, visible, sensitive, etc), and should change when the action's state
changes. When the proxy is activated, it should activate its action.
activate
public void activate()
Emits the "activate" signal on the specified action, if it isn't
insensitive. This gets called by the proxy widgets when they get
activated.
It can also be used to manually activate an action.
addListener
public void addListener(ActionListener listener)
Register an object to receive action activation event notification.
listener
- The object that has implemented the ActionListener interface
that is to receive the activation events.
connectAccelerator
public void connectAccelerator()
Installs the accelerator for action if action has an accel path and
group. Since multiple proxies may independently trigger the installation
of the accelerator, the action counts the number of times this function
has been called and doesn't remove the accelerator until
disconnectAccelerator()
has been called as many times.
connectProxy
public void connectProxy(Widget proxy)
Connects a widget to an action object as a proxy. Synchronises various
properties of the action with the widget (such as label text, icon,
tooltip, etc), and attaches a callback so that the action gets activated
when the proxy widget does.
If the widget is already connected to an action, it is disconnected
first.
createIcon
public Widget createIcon(IconSize iconSize)
This function is intended for use by action implementations to create
icons displayed in the proxy widgets.
iconSize
- the size of the icon that should be created
- a widget that displays the icon for this action
createMenuItem
public Widget createMenuItem()
Creates a menu item widget that proxies for the given action.
- a menu item connected to the action
createToolItem
public Widget createToolItem()
Creates a toolbar item widget that proxies for the given action.
- a toolbar item connected to the action
disconnectAccelerator
public void disconnectAccelerator()
disconnectProxy
public void disconnectProxy(Widget proxy)
Disconnects a proxy widget from an action. Does not destroy the widget,
however.
getAcceleratorPath
public String getAcceleratorPath()
getName
public String getName()
Returns the name of the action.
getProxies
public List getProxies()
Returns the proxy widgets for an action.
getType
public static Type getType()
Retrieve the runtime type used by the GLib library.
isSensitive
public boolean isSensitive()
isVisible
public boolean isVisible()
removeListener
public void removeListener(ActionListener listener)
Unregister an object that was receiving focus event notification.
listener
- The object that is to no longer receive focus events.
setAccelGroup
public void setAccelGroup(AccelGroup group)
Sets the
AccelGroup
in which the accelerator for this
action will be installed.
group
- an AccelGroup or null
setAccelPath
public void setAccelPath(String path)
Sets the accel path for this action. All proxy widgets associated with
the action will have this accel path, so that their accelerators are
consistent.
path
- The accelerator path
setSensitive
public void setSensitive(boolean sensitive)
setVisible
public void setVisible(boolean visible)