Many QuickTime services, such as image compression and decompression, are provided by components.
The set of classes whose the base class is the
QTPlgComponentService allows you to access to the services provided by many of these components.
This class defines properties and methods common to all of its derived classes. The execution of specific tasks is
delegated to the appropriate specialized class.
The class has not constructor at all (you can always use the Realbasic common constructor syntax, of course, but you will
obtain an usless object). Its destructor, will be
implicitly invoked every time one of its derived classes will be destroyed.
The class destructor will also close the connection to the component in use if any.
Anyway, once a new instance of a class derived from QTPlgComponentService is returned, it is good practice to check the
class property to
be sure that the new object can be used. As a rule of thumb, a class derived from
QTPlgComponentService is valid if it has obtained access to the component to be used
(that is the value of the
property is not 0)
returns the identifier to the instance of the component in use (aka component instance).
useful for toolbox programmers (use with care: you could invalidate the component instance
causing unpredictable results (probably an application crash))
the default file type that will be used if the
property has
not been changed
the default file creator that will be used if the
property
has not been changed
indicates the file type that will be used when outputting data to a file; usually, at instantiation time, is the same as the
property
indicates the file creator that will be used when outputting data to a file; usually, at instantiation time, is the same as the
property
specifies if the currently selected component features a settings dialog. If true,
you can use the class method to display it
instructs the class to use its default progress procedure if any (note that not all of the component services
classes feature a default progress procedure)
specifies if the currently selected component can process data in background as well. This property is effective only for QuickTime 6.4 and later on MacOS; it is always set to
false in any other circumstance. Note that not all of the QTPlgComponentService sub classes support processing data in background
specifies if the currently selected component has to process data in a background thread; this property is settable only if the
property returns true
indicates the number of background threads currently attached to the component instance in use
specifies a free text that you can use to store any annotations you need when saving the current class settings to a disk (see
)
a summary of the current component settings in form of human readable string (note that this feature is not available to all of
the component services classes)
returns detailed informations about the component currently in use
specifies your custom progress callback. If this property is set to a
instance of the
class, it will be invoked instead of the
(if any) anytime you perform a specific task featured by the component in use
[Deprecated]: since version 6.6 of the plugin this property is deprecated
and will be removed from a future plugin version; use the
class instead
the current component settings in their native format
if the selected component has some user interface (check the
property to check it), this method allows you
to display its dialog box and use it to configure the component settings.
Cause many components have several parameters to configure, this function, will be very
useful to manage complex component configuration settings
same as the method but, in this case, the dialog will be
displayed as a sheet window within the window specified by the
w parameter
requires MacOSX and Quicktime version 6.4 or later; otherwise, the behaviour is the same as the
method
allows you to restore a previously saved configuration for the currently selected component. Cause
the
QTPlugin settings file contains informations about the component that generated this configuration, this function will fail
if you try to use
settings not appropriate for the component in use. You specify the source settings file by using the
f parameter;
the format of this file is cross–platform
by using this method you can save the current component settings to the
QTPlugin settings file
specified by the
f parameter; if the target file already exists in the specified location,
this function will overwrite it with the new component settings. The format of this file is cross–platform