API reference - Class Dispatcher

Notation used in Ruby API documentation

Module: lay

Description: Root of the configuration space in the plugin context and menu dispatcher

This class provides access to the root configuration space in the context of plugin programming. You can use this class to obtain configuration parameters from the configuration tree during plugin initialization. However, the preferred way of plugin configuration is through Plugin#configure.

Currently, the application object provides an identical entry point for configuration modification. For example, "Application::instance.set_config" is identical to "Dispatcher::instance.set_config". Hence there is little motivation for the Dispatcher class currently and this interface may be modified or removed in the future. This class has been introduced in version 0.25 as 'PluginRoot'. It is renamed and enhanced as 'Dispatcher' in 0.27.

Public constructors

new Dispatcher ptrnewCreates a new object of this class

Public methods

void_createEnsures the C++ object is created
void_destroyExplicitly destroys the object
[const]bool_destroyed?Returns a value indicating whether the object was already destroyed
[const]bool_is_const_object?Returns a value indicating whether the reference is a const reference
void_manageMarks the object as managed by the script side.
void_unmanageMarks the object as no longer owned by the script side.
voidclear_configClears the configuration parameters
voidcommit_configCommits the configuration settings
variantget_config(string name)Gets the value of a local configuration parameter
string[]get_config_namesGets the configuration parameter names
boolread_config(string file_name)Reads the configuration from a file
voidset_config(string name,
string value)
Set a local configuration parameter with the given name to the given value
boolwrite_config(string file_name)Writes configuration to a file

Public static methods and constants

Dispatcher ptrinstanceGets the singleton instance of the Dispatcher object

Deprecated methods (protected, public, static, non-static and constructors)

voidcreateUse of this method is deprecated. Use _create instead
voiddestroyUse of this method is deprecated. Use _destroy instead
[const]booldestroyed?Use of this method is deprecated. Use _destroyed? instead
[const]boolis_const_object?Use of this method is deprecated. Use _is_const_object? instead

Detailed description

_create

Signature: void _create

Description: Ensures the C++ object is created

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

_destroy

Signature: void _destroy

Description: Explicitly destroys the object

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

_destroyed?

Signature: [const] bool _destroyed?

Description: Returns a value indicating whether the object was already destroyed

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

_is_const_object?

Signature: [const] bool _is_const_object?

Description: Returns a value indicating whether the reference is a const reference

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

_manage

Signature: void _manage

Description: Marks the object as managed by the script side.

After calling this method on an object, the script side will be responsible for the management of the object. This method may be called if an object is returned from a C++ function and the object is known not to be owned by any C++ instance. If necessary, the script side may delete the object if the script's reference is no longer required.

Usually it's not required to call this method. It has been introduced in version 0.24.

_unmanage

Signature: void _unmanage

Description: Marks the object as no longer owned by the script side.

Calling this method will make this object no longer owned by the script's memory management. Instead, the object must be managed in some other way. Usually this method may be called if it is known that some C++ object holds and manages this object. Technically speaking, this method will turn the script's reference into a weak reference. After the script engine decides to delete the reference, the object itself will still exist. If the object is not managed otherwise, memory leaks will occur.

Usually it's not required to call this method. It has been introduced in version 0.24.

clear_config

Signature: void clear_config

Description: Clears the configuration parameters

commit_config

Signature: void commit_config

Description: Commits the configuration settings

Some configuration options are queued for performance reasons and become active only after 'commit_config' has been called. After a sequence of set_config calls, this method should be called to activate the settings made by these calls.

create

Signature: void create

Description: Ensures the C++ object is created

Use of this method is deprecated. Use _create instead

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

destroy

Signature: void destroy

Description: Explicitly destroys the object

Use of this method is deprecated. Use _destroy instead

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

destroyed?

Signature: [const] bool destroyed?

Description: Returns a value indicating whether the object was already destroyed

Use of this method is deprecated. Use _destroyed? instead

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

get_config

Signature: variant get_config (string name)

Description: Gets the value of a local configuration parameter

name:The name of the configuration parameter whose value shall be obtained (a string)
Returns:The value of the parameter or nil if there is no such parameter

get_config_names

Signature: string[] get_config_names

Description: Gets the configuration parameter names

Returns:A list of configuration parameter names

This method returns the names of all known configuration parameters. These names can be used to get and set configuration parameter values.

instance

Signature: [static] Dispatcher ptr instance

Description: Gets the singleton instance of the Dispatcher object

Returns:The instance

is_const_object?

Signature: [const] bool is_const_object?

Description: Returns a value indicating whether the reference is a const reference

Use of this method is deprecated. Use _is_const_object? instead

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

new

Signature: [static] new Dispatcher ptr new

Description: Creates a new object of this class

Python specific notes:
This method is the default initializer of the object.

read_config

Signature: bool read_config (string file_name)

Description: Reads the configuration from a file

Returns:A value indicating whether the operation was successful

This method silently does nothing, if the config file does not exist. If it does and an error occurred, the error message is printed on stderr. In both cases, false is returned.

set_config

Signature: void set_config (string name, string value)

Description: Set a local configuration parameter with the given name to the given value

name:The name of the configuration parameter to set
value:The value to which to set the configuration parameter

This method sets a configuration parameter with the given name to the given value. Values can only be strings. Numerical values have to be converted into strings first. Local configuration parameters override global configurations for this specific view. This allows for example to override global settings of background colors. Any local settings are not written to the configuration file.

write_config

Signature: bool write_config (string file_name)

Description: Writes configuration to a file

Returns:A value indicating whether the operation was successful

If the configuration file cannot be written, false is returned but no exception is thrown.