API reference - Class Application

Notation used in Ruby API documentation

Description: The application object

Class hierarchy: Application » QApplication » QCoreApplication » QObject

The application object is the main port from which to access all the internals of the application, in particular the main window.

Public constructors

new Application 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.
[const]stringapplication_data_pathReturn the application's data path (where the configuration file is stored for example)
intexecuteExecute the application's main loop
voidexit(int result)Exit the application with the given exit status
[const]stringget_config(string name)Query a configuration parameter
[const]string[]get_config_namesQuery the configuration parameter names
[const]stringinst_pathReturn the application's installation path (where the executable is located)
[const]boolis_editable?Return true if the application is in editable mode
[const]string[]klayout_pathReturn the KLayout path (search path for KLayout components)
[const]MainWindow ptrmain_windowReturn a reference to the main window
voidprocess_eventsProcess pending events
boolread_config(string file_name)Read the configuration from a file
voidset_config(string name,
string value)
Set a configuration parameter with the given name to the given value
[const]stringversionReturn the application's version string
boolwrite_config(string file_name)Write configuration to a file

Public static methods and constants

Application ptrinstanceReturn the singleton instance of the application

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
intexecUse of this method is deprecated. Use execute instead
[const]boolis_const_object?Use of this method is deprecated. Use _is_const_object? instead

Detailed description

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.

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.

[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.

[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.

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.

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.

[const] string application_data_path

Description: Return the application's data path (where the configuration file is stored for example)

This method has been added in version 0.22.

void create

Description: Ensures the C++ object is created

Use of this method is deprecated. Use _create instead

void destroy

Description: Explicitly destroys the object

Use of this method is deprecated. Use _destroy instead

[const] bool destroyed?

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

Use of this method is deprecated. Use _destroyed? instead

int exec

Description: Execute the application's main loop

Use of this method is deprecated. Use execute instead

int execute

Description: Execute the application's main loop

This method must be called in order to execute the application in the main script if a script is provided.

Python specific notes:

This method is available as method 'exec_' in Python

void exit(int result)

Description: Exit the application with the given exit status

This method should be called instead of simply shutting down the process. It performs some important cleanup without which the process might crash. If the result code is 0 (success), the configuration file will be updated unless that has been disabled by the -nc command line switch. This method has been added in version 0.22.

[const] string get_config(string name)

Description: Query a configuration parameter

name:The name of the configuration parameter whose value shall be obtained (a string)
Returns:The value of the parameter

This method returns the value of the given configuration parameter. If the parameter is not known, an exception will be thrown. Use get_config_names to obtain a list of all configuration parameter names available.

Configuration parameters are always stored as strings. The actual format of this string is specific to the configuration parameter. The values delivered by this method correspond to the values stored in the configuration file

[const] string[] get_config_names

Description: Query 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.

[const] string inst_path

Description: Return the application's installation path (where the executable is located)

This method has been added in version 0.18. Version 0.22 offers the method klayout_path which delivers all components of the search path.

[static] Application ptr instance

Description: Return the singleton instance of the application

There is exactly one instance of the application. This instance can be obtained with this method.

[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

[const] bool is_editable?

Description: Return true if the application is in editable mode

[const] string[] klayout_path

Description: Return the KLayout path (search path for KLayout components)

The result is an array containing the components of the path.

This method has been added in version 0.22.

[const] MainWindow ptr main_window

Description: Return a reference to the main window

Returns:A object reference to the main window object.

[static] new Application ptr new

Description: Creates a new object of this class

Python specific notes:

This method is the default initializer of the object

void process_events

Description: Process pending events

This method processes pending events and dispatches them internally. Calling this method periodically during a long operation keeps the application 'alive'

bool read_config(string file_name)

Description: Read the configuration from a file

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

void set_config(string name,string value)

Description: Set a 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 the configuration parameter with the given name to the given value. Values can only be strings. Numerical values have to be converted into strings first. The actual format of the value depends on the configuration parameter. The name must be one of the names returned by get_config_names. It is possible to write an arbitrary name/value pair into the configuration database which then is written to the configuration file.

[const] string version

Description: Return the application's version string

bool write_config(string file_name)

Description: Write configuration to a file

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