Package ch.bailu.gtk.gio

Klasse Action

java.lang.Object
ch.bailu.gtk.type.Type
ch.bailu.gtk.type.Pointer
ch.bailu.gtk.gobject.Object
ch.bailu.gtk.type.PropertyHolder
ch.bailu.gtk.type.Interface
ch.bailu.gtk.gio.Action
Alle implementierten Schnittstellen:
PointerInterface
public class Action extends Interface
`GAction` represents a single named action.

The main interface to an action is that it can be activated with
[method@Gio.Action.activate]. This results in the 'activate' signal being
emitted. An activation has a `GVariant` parameter (which may be
`NULL`). The correct type for the parameter is determined by a static
parameter type (which is given at construction time).

An action may optionally have a state, in which case the state may be
set with [method@Gio.Action.change_state]. This call takes a [type@GLib.Variant]. The
correct type for the state is determined by a static state type
(which is given at construction time).

The state may have a hint associated with it, specifying its valid
range.

`GAction` is merely the interface to the concept of an action, as
described above. Various implementations of actions exist, including
[class@Gio.SimpleAction].

In all cases, the implementing class is responsible for storing the
name of the action, the parameter type, the enabled state, the optional
state type and the state and emitting the appropriate signals when these
change. The implementor is responsible for filtering calls to
[method@Gio.Action.activate] and [method@Gio.Action.change_state]
for type safety and for the state being enabled.

Probably the only useful thing to do with a `GAction` is to put it
inside of a [class@Gio.SimpleActionGroup].

https://docs.gtk.org/gio/iface.Action.html

  • Konstruktordetails

  • Methodendetails

    • getClassHandler

      public static ClassHandler getClassHandler()

    • activate

      public void activate(@Nullable Variant parameter)
      Activates the action.

      @parameter must be the correct type of parameter for the action (ie:
      the parameter type given at construction time). If the parameter
      type was `NULL` then @parameter must also be `NULL`.

      If the @parameter [type@GLib.Variant] is floating, it is consumed.
      Parameter:
      parameter - the parameter to the activation

    • changeState

      public void changeState(@Nonnull Variant value)
      Request for the state of @action to be changed to @value.

      The action must be stateful and @value must be of the correct type.
      See [method@Gio.Action.get_state_type].

      This call merely requests a change. The action may refuse to change
      its state or may change its state to something other than @value.
      See [method@Gio.Action.get_state_hint].

      If the @value [type@GLib.Variant] is floating, it is consumed.
      Parameter:
      value - the new state

    • getEnabled

      public boolean getEnabled()
      Checks if @action is currently enabled.

      An action must be enabled in order to be activated or in order to
      have its state changed from outside callers.
      Gibt zurück:
      whether the action is enabled

    • getName

      public Str getName()
      Queries the name of @action.
      Gibt zurück:
      the name of the action

    • getParameterType

      public VariantType getParameterType()
      Queries the type of the parameter that must be given when activating
      @action.

      When activating the action using [method@Gio.Action.activate], the
      [type@GLib.Variant] given to that function must be of the type returned by
      this function.

      In the case that this function returns `NULL`, you must not give any
      [type@GLib.Variant], but `NULL` instead.
      Gibt zurück:
      the parameter type

    • getState

      public Variant getState()
      Queries the current state of @action.

      If the action is not stateful then `NULL` will be returned. If the
      action is stateful then the type of the return value is the type
      given by [method@Gio.Action.get_state_type].

      The return value (if non-`NULL`) should be freed with
      [method@GLib.Variant.unref] when it is no longer required.
      Gibt zurück:
      the current state of the action

    • getStateHint

      public Variant getStateHint()
      Requests a hint about the valid range of values for the state of
      @action.

      If `NULL` is returned it either means that the action is not stateful
      or that there is no hint about the valid range of values for the
      state of the action.

      If a [type@GLib.Variant] array is returned then each item in the array is a
      possible value for the state. If a [type@GLib.Variant] pair (ie: two-tuple) is
      returned then the tuple specifies the inclusive lower and upper bound
      of valid values for the state.

      In any case, the information is merely a hint. It may be possible to
      have a state value outside of the hinted range and setting a value
      within the range may fail.

      The return value (if non-`NULL`) should be freed with
      [method@GLib.Variant.unref] when it is no longer required.
      Gibt zurück:
      the state range hint

    • getStateType

      public VariantType getStateType()
      Queries the type of the state of @action.

      If the action is stateful (e.g. created with
      [ctor@Gio.SimpleAction.new_stateful]) then this function returns the
      [type@GLib.VariantType] of the state. This is the type of the initial value
      given as the state. All calls to [method@Gio.Action.change_state] must give a
      [type@GLib.Variant] of this type and [method@Gio.Action.get_state] will return a
      [type@GLib.Variant] of the same type.

      If the action is not stateful (e.g. created with [ctor@Gio.SimpleAction.new])
      then this function will return `NULL`. In that case, [method@Gio.Action.get_state]
      will return `NULL` and you must not call [method@Gio.Action.change_state].
      Gibt zurück:
      the state type, if the action is stateful

    • nameIsValid

      public static boolean nameIsValid(@Nonnull Str action_name)
      Checks if @action_name is valid.

      @action_name is valid if it consists only of alphanumeric characters,
      plus `-` and `.`. The empty string is not a valid action name.

      It is an error to call this function with a non-UTF-8 @action_name.
      @action_name must not be `NULL`.
      Parameter:
      action_name - a potential action name
      Gibt zurück:
      `TRUE` if @action_name is valid

    • printDetailedName

      public static Str printDetailedName(@Nonnull Str action_name, @Nullable Variant target_value)
      Formats a detailed action name from @action_name and @target_value.

      It is an error to call this function with an invalid action name.

      This function is the opposite of [func@Gio.Action.parse_detailed_name].
      It will produce a string that can be parsed back to the @action_name
      and @target_value by that function.

      See that function for the types of strings that will be printed by
      this function.
      Parameter:
      action_name - a valid action name
      target_value - a [type@GLib.Variant] target value, or `NULL`
      Gibt zurück:
      a detailed format string

    • getTypeID

      public static long getTypeID()

    • getParentTypeID

      public static long getParentTypeID()

    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()

    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()

    • getInstanceSize

      public static int getInstanceSize()