Filter package:gi-gtk

A GtkFilter object describes the filtering to be performed by a FilterListModel. The model will use the filter to determine if it should include items or not by calling filterMatch for each item and only keeping the ones that the function returns True for. Filters may change what items they match through their lifetime. In that case, they will emit the Filter::changed signal to notify that previous filter results are no longer valid and that items should be checked again via filterMatch. GTK provides various pre-made filter implementations for common filtering operations. These filters often include properties that can be linked to various widgets to easily allow searches. However, in particular for large lists or complex search methods, it is also possible to subclass GtkFilter and provide one's own filter.

Memory-managed wrapper type.

Describes changes in a filter in more detail and allows objects using the filter to optimize refiltering items. If you are writing an implementation and are not sure which value to pass, FilterChangeDifferent is always a correct choice.

The filter change cannot be described with any of the other enumeration values.

The filter is less strict than it was before: All items that it used to return True for still return True, others now may, too.

The filter is more strict than it was before: All items that it used to return False for still return False, others now may, too.

Describes the known strictness of a filter. Note that for filters where the strictness is not known, FilterMatchSome is always an acceptable value, even if a filter does match all or no items.

The filter matches all items, filterMatch will alays return True.

The filter does not match any item, filterMatch will always return False.

The filter matches some items, filterMatch may return True or False

Emitted whenever the filter changed. Users of the filter should then check items again via filterMatch. GtkFilterListModel handles this signal automatically. Depending on the change parameter, not all items need to be checked, but only some. Refer to the FilterChange documentation for details.

GtkFilterListModel is a list model that filters the elements of the underlying model according to a GtkFilter. It hides some elements from the other model according to criteria given by a GtkFilter. The model can be set up to do incremental filtering, so that filtering long lists doesn't block the UI. See filterListModelSetIncremental for details. GtkFilterListModel passes through sections from the underlying model.

Memory-managed wrapper type.

Notifies all users of the filter that it has changed. This emits the Filter::changed signal. Users of the filter should then check items again via filterMatch. Depending on the change parameter, not all items need to be changed, but only some. Refer to the FilterChange documentation for details. This function is intended for implementers of GtkFilter subclasses and should not be called from other functions.

Gets the known strictness of filters. If the strictness is not known, FilterMatchSome is returned. This value may change after emission of the Filter::changed signal. This function is meant purely for optimization purposes, filters can choose to omit implementing it, but GtkFilterListModel uses it.

Checks if the given item is matched by the filter or not.

Gets the GtkFilter currently set on self.

Returns whether incremental filtering is enabled. See filterListModelSetIncremental.

Gets the model currently filtered or Nothing if none.

Returns the number of items that have not been filtered yet. You can use this value to check if self is busy filtering by comparing the return value to 0 or you can compute the percentage of the filter remaining by dividing the return value by the total number of items in the underlying model:

c code

pending = gtk_filter_list_model_get_pending (self);
model = gtk_filter_list_model_get_model (self);
percentage = pending / (double) g_list_model_get_n_items (model);

If no filter operation is ongoing - in particular when FilterListModel:incremental is False - this function returns 0.

Creates a new GtkFilterListModel that will filter model using the given filter.

Sets the filter used to filter items.

Sets the filter model to do an incremental sort. When incremental filtering is enabled, the GtkFilterListModel will not run filters immediately, but will instead queue an idle handler that incrementally filters the items and adds them to the list. This of course means that items are not instantly added to the list, but only appear incrementally. When your filter blocks the UI while filtering, you might consider turning this on. Depending on your model and filters, this may become interesting around 10,000 to 100,000 items. By default, incremental filtering is disabled. See filterListModelGetPending for progress information about an ongoing incremental filtering operation.