return false and set error appropriately if present.
gio.initable_mixin
Module for Initable interface mixin
Templates 2
tmplInitableT()
gio.initable.Initable is implemented by objects that can fail during initialization. If an object implements this interface then it must be initialized as the first thing after construction, either via gio.initable.Initable.init_ or gio.async_initable.AsyncInitable.initAsync (the latter is only available if it also implements gio.async_initable.AsyncInitable).
If the object is not initialized, or initialization returns with an error, then all operations on the object except [gobject.object.ObjectWrap.ref_] and [gobject.object.ObjectWrap.unref] are considered to be invalid, and have undefined behaviour. They will often fail with func@GLib.critical or func@GLib.warning, but this must not be relied on.
Users of objects implementing this are not intended to use the interface method directly, instead it will be used automatically in various ways. For C applications you generally just call gio.initable.Initable.new_ directly, or indirectly via a foo_thing_new() wrapper. This will call gio.initable.Initable.init_ under the cover, returning NULL and setting a glib.error.ErrorWrap on failure (at which point the instance is unreferenced).
For bindings in languages where the native constructor supports exceptions the binding could check for objects implementing gio.initable.Initable during normal construction and automatically initialize them, throwing an exception on failure.
Functions
bool init_(gio.cancellable.Cancellable cancellable = null)
Initializes the object implementing the interface.
This method is intended for language bindings. If writing in C, gio.initable.Initable.new_ should typically be used instead.
The object must be initialized before any real use after initial construction, either with this function or gio.async_initable.AsyncInitable.initAsync.
Implementations may also support cancellation. If cancellable is not null, then initialization can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error gio.types.IOErrorEnum.Cancelled will be returned. If cancellable is not null and the object doesn't support cancellable initialization the error gio.types.IOErrorEnum.NotSupported will be returned.
If the object is not initialized, or initialization returns with an error, then all operations on the object except gobject.object.ObjectWrap.ref_ and gobject.object.ObjectWrap.unref are considered to be invalid, and have undefined behaviour. See the introduction for more details.
Callers should not assume that a class which implements #GInitable can be initialized multiple times, unless the class explicitly documents itself as supporting this. Generally, a class’ implementation of init() can assume (and assert) that it will only be called once. Previously, this documentation recommended all #GInitable implementations should be idempotent; that recommendation was relaxed in GLib 2.54.
If a class explicitly supports being initialized multiple times, it is recommended that the method is idempotent: multiple calls with the same arguments should return the same results. Only the first call initializes the object; further calls return the result of the first call.
One reason why a class might need to support idempotent initialization is if it is designed to be used via the singleton pattern, with a #GObjectClass.constructor that sometimes returns an existing instance. In this pattern, a caller would expect to be able to call gio.initable.Initable.init_ on the result of gobject.object.ObjectWrap.new_, regardless of whether it is in fact a new instance.
Parameters
cancellable | optional #GCancellable object, null to ignore. |
Returns
true if successful. If an error has occurred, this function will
Throws
tmplInitableGidBuilderT()
Fluent builder implementation template for gio.initable.Initable