/** * @defgroup Elm_Genlist Genlist (Generic list) * @ingroup Elementary * * @image html genlist_inheritance_tree.png * @image latex genlist_inheritance_tree.eps * * @image html img/genlist.png * @image latex img/genlist.eps * * This widget aims to have more expansive list than the simple list in * Elementary that could have more flexible items and allow many more entries * while still being fast and low on memory usage. At the same time it was * also made to be able to do tree structures. But the price to pay is more * complexity when it comes to usage. If all you want is a simple list with * icons and a single text, use the normal @ref List object. * * Genlist has a fairly large API, mostly because it's relatively complex, * trying to be both expansive, powerful and efficient. First we will begin * an overview on the theory behind genlist. * * This widget inherits from the @ref Layout one, so that all the * functions acting on it also work for genlist objects. * * This widget implements the @b @ref elm-scrollable-interface * interface, so that all (non-deprecated) functions for the base @ref * Scroller widget also work for genlists. * * Some calls on the genlist's API are marked as @b deprecated, as * they just wrap the scrollable widgets counterpart functions. Use * the ones we point you to, for each case of deprecation here, * instead -- eventually the deprecated ones will be discarded (next * major release). * * @section Genlist_Item_Class Genlist item classes - creating items * * In order to have the ability to add and delete items on the fly, genlist * implements a class (callback) system where the application provides a * structure with information about that type of item (genlist may contain * multiple different items with different classes, states and styles). * Genlist will call the functions in this struct (methods) when an item is * "realized" (i.e., created dynamically, while the user is scrolling the * list). All objects will simply be deleted when no longer needed with * evas_object_del(). The #Elm_Genlist_Item_Class structure contains the * following members: * - @c item_style - This is a constant string and simply defines the name * of the item style. It @b must be specified and the default should be @c * "default". * - @c decorate_item_style - This is a constant string and simply defines the name * of the decorate mode item style. It is used to specify decorate mode item style. It can be * used when you call elm_genlist_item_decorate_mode_set(). * - @c decorate_all_item_style - This is a constant string and simply defines the name * of the decorate all item style. It is used to specify decorate all item style. It can be * used to set selection, checking and deletion mode. This is used when you * call elm_genlist_decorate_mode_set(). * - @c func - A struct with pointers to functions that will be called when * an item is going to be actually created. All of them receive a @c data * parameter that will point to the same data passed to * elm_genlist_item_append() and related item creation functions, and an @c * obj parameter that points to the genlist object itself. * * The function pointers inside @c func are @c text_get, @c content_get, @c * state_get and @c del. The 3 first functions also receive a @c part * parameter described below. A brief description of these functions follows: * * - @c text_get - The @c part parameter is the name string of one of the * existing text parts in the Edje group implementing the item's theme. * This function @b must return a strdup'()ed string, as the caller will * free() it when done. See #Elm_Genlist_Item_Text_Get_Cb. * - @c content_get - The @c part parameter is the name string of one of the * existing (content) swallow parts in the Edje group implementing the item's * theme. It must return @c NULL, when no content is desired, or a valid * object handle, otherwise. The object will be deleted by the genlist on * its deletion or when the item is "unrealized". * See #Elm_Genlist_Item_Content_Get_Cb. * - @c func.state_get - The @c part parameter is the name string of one of * the state parts in the Edje group implementing the item's theme. Return * @c EINA_FALSE for false/off or @c EINA_TRUE for true/on. Genlists will * emit a signal to its theming Edje object with @c "elm,state,xxx,active" * and @c "elm" as "emission" and "source" arguments, respectively, when * the state is true (the default is false), where @c xxx is the name of * the (state) part. See #Elm_Genlist_Item_State_Get_Cb. * - @c func.del - This is intended for use when genlist items are deleted, * so any data attached to the item (e.g. its data parameter on creation) * can be deleted. See #Elm_Genlist_Item_Del_Cb. * * available item styles: * - default * - default_style - The text part is a textblock * - double_label * - icon_top_text_bottom * - group_index * - one_icon - Only 1 icon (left) (since 1.7) * - end_icon - Only 1 icon (at end/right) (since 1.7) * - no_icon - No icon (at end/right) (since 1.7) * - full - Only 1 icon, elm.swallow.content, which consumes whole area of * genlist item (since 1.7) * * If one wants to use more icons and texts than are offered in theme, there * are two solutions. One is to use 'full' style that has one big swallow part. * You can swallow anything there. The other solution is to customize genlist * item style in application side by using elm_theme_extension_add() and its * own edc. Please refer @ref theme_example_01 for that. * * @section Genlist_Items Structure of items * * An item in a genlist can have 0 or more texts (they can be regular * text or textblock Evas objects - that's up to the style to determine), 0 * or more contents (which are simply objects swallowed into the genlist item's * theming Edje object) and 0 or more boolean states, which have the * behavior left to the user to define. The Edje part names for each of * these properties will be looked up, in the theme file for the genlist, * under the Edje (string) data items named @c "labels", @c "contents" and @c * "states", respectively. For each of those properties, if more than one * part is provided, they must have names listed separated by spaces in the * data fields. For the default genlist item theme, we have @b one text * part (@c "elm.text"), @b two content parts (@c "elm.swallow.icon" and @c * "elm.swallow.end") and @b no state parts. * * A genlist item may be at one of several styles. Elementary provides one * by default - "default", but this can be extended by system or application * custom themes/overlays/extensions (see @ref Theme "themes" for more * details). * * @section Genlist_Manipulation Editing and Navigating * * Items can be added by several calls. All of them return a @ref * Elm_Object_Item handle that is an internal member inside the genlist. * They all take a data parameter that is meant to be used for a handle to * the applications internal data (eg. the struct with the original item * data). The parent parameter is the parent genlist item this belongs to if * it is a tree or an indexed group, and NULL if there is no parent. The * flags can be a bitmask of #ELM_GENLIST_ITEM_NONE, #ELM_GENLIST_ITEM_TREE * and #ELM_GENLIST_ITEM_GROUP. If #ELM_GENLIST_ITEM_TREE is set then this * item is displayed as an item that is able to expand and have child items. * If #ELM_GENLIST_ITEM_GROUP is set then this item is group index item that * is displayed at the top until the next group comes. The func parameter is * a convenience callback that is called when the item is selected and the * data parameter will be the func_data parameter, @c obj be the genlist * object and event_info will be the genlist item. * * elm_genlist_item_append() adds an item to the end of the list, or if * there is a parent, to the end of all the child items of the parent. * elm_genlist_item_prepend() is the same but adds to the beginning of * the list or children list. elm_genlist_item_insert_before() inserts at * item before another item and elm_genlist_item_insert_after() inserts after * the indicated item. * * The application can clear the list with elm_genlist_clear() which deletes * all the items in the list and elm_object_item_del() will delete a specific * item. elm_genlist_item_subitems_clear() will clear all items that are * children of the indicated parent item. * * To help inspect list items you can jump to the item at the top of the list * with elm_genlist_first_item_get() which will return the item pointer, and * similarly elm_genlist_last_item_get() gets the item at the end of the list. * elm_genlist_item_next_get() and elm_genlist_item_prev_get() get the next * and previous items respectively relative to the indicated item. Using * these calls you can walk the entire item list/tree. Note that as a tree * the items are flattened in the list, so elm_genlist_item_parent_get() will * let you know which item is the parent (and thus know how to skip them if * wanted). * * @section Genlist_Multi_Selection Multi-selection * * If the application wants multiple items to be able to be selected, * elm_genlist_multi_select_set() can enable this. If the list is * single-selection only (the default), then elm_genlist_selected_item_get() * will return the selected item, if any, or NULL if none is selected. If the * list is multi-select then elm_genlist_selected_items_get() will return a * list (that is only valid as long as no items are modified (added, deleted, * selected or unselected)). * * @section Genlist_Usage_Hints Usage hints * * There are also convenience functions. elm_object_item_widget_get() will * return the genlist object the item belongs to. elm_genlist_item_show() * will make the scroller scroll to show that specific item so its visible. * elm_object_item_data_get() returns the data pointer set by the item * creation functions. * * If an item changes (state of boolean changes, text or contents change), * then use elm_genlist_item_update() to have genlist update the item with * the new state. Genlist will re-realize the item and thus call the functions * in the _Elm_Genlist_Item_Class for that item. * * To programmatically (un)select an item use elm_genlist_item_selected_set(). * To get its selected state use elm_genlist_item_selected_get(). Similarly * to expand/contract an item and get its expanded state, use * elm_genlist_item_expanded_set() and elm_genlist_item_expanded_get(). And * again to make an item disabled (unable to be selected and appear * differently) use elm_object_item_disabled_set() to set this and * elm_object_item_disabled_get() to get the disabled state. * * In general to indicate how the genlist should expand items horizontally to * fill the list area, use elm_genlist_mode_set(). Valid modes are * ELM_LIST_LIMIT, ELM_LIST_COMPRESS and ELM_LIST_SCROLL. The default is * ELM_LIST_SCROLL. This mode means that if items are too wide to fit, the * scroller will scroll horizontally. Otherwise items are expanded to * fill the width of the viewport of the scroller. If it is * ELM_LIST_LIMIT, items will be expanded to the viewport width * if larger than the item, but genlist widget width is * limited to the largest item. Do not use ELM_LIST_LIMIT mode with homogeneous * mode turned on. ELM_LIST_COMPRESS can be combined with a different style * that uses edjes' ellipsis feature (cutting text off like this: "tex..."). * * Items will call their selection func and callback only once when first becoming * selected. Any further clicks will do nothing, unless you enable always * select with elm_genlist_select_mode_set() as ELM_OBJECT_SELECT_MODE_ALWAYS. * This means even if selected, every click will make the selected callbacks * be called. elm_genlist_select_mode_set() as ELM_OBJECT_SELECT_MODE_NONE will * turn off the ability to select items entirely and they will neither * appear selected nor call selected callback functions. * * Remember that you can create new styles and add your own theme augmentation * per application with elm_theme_extension_add(). If you absolutely must * have a specific style that overrides any theme the user or system sets up * you can use elm_theme_overlay_add() to add such a file. * * @section Genlist_Implementation Implementation * * Evas tracks every object you create. Every time it processes an event * (mouse move, down, up etc.) it needs to walk through objects and find out * what event that affects. Even worse every time it renders display updates, * in order to just calculate what to re-draw, it needs to walk through many * many many objects. Thus, the more objects you keep active, the more * overhead Evas has in just doing its work. It is advisable to keep your * active objects to the minimum working set you need. Also remember that * object creation and deletion carries an overhead, so there is a * middle-ground, which is not easily determined. But don't keep massive lists * of objects you can't see or use. Genlist does this with list objects. It * creates and destroys them dynamically as you scroll around. It groups them * into blocks so it can determine the visibility etc. of a whole block at * once as opposed to having to walk the whole list. This 2-level list allows * for very large numbers of items to be in the list (tests have used up to * 2,000,000 items). Also genlist employs a queue for adding items. As items * may be different sizes, every item added needs to be calculated as to its * size and thus this presents a lot of overhead on populating the list, this * genlist employs a queue. Any item added is queued and spooled off over * time, actually appearing some time later, so if your list has many members * you may find it takes a while for them to all appear, with your process * consuming a lot of CPU while it is busy spooling. * * Genlist also implements a tree structure for items, but it does so with * callbacks to the application, with the application filling in tree * structures when requested (allowing for efficient building of a very * deep tree that could even be used for file-management). * See the above smart signal callbacks for details. * * @section Genlist_Smart_Events Genlist smart events * * This widget emits the following signals, besides the ones sent from * @ref Layout: * - @c "activated" - The user has double-clicked or pressed * (enter|return|spacebar) on an item. The @p event_info parameter is the * item that was activated. * - @c "pressed" - The user pressed an item. The @p event_info * parameter is the item that was pressed. * - @c "released" - The user released an item. The @p event_info * parameter is the item that was released. * - @c "clicked,double" - The user has double-clicked an item. The @c * event_info parameter is the item that was double-clicked. * - @c "clicked,right" - The user has right-clicked an item. The @c * event_info parameter is the item that was right-clicked. (since 1.13) * - @c "selected" - This is called when a user has made an item selected. * The event_info parameter is the genlist item that was selected. * - @c "unselected" - This is called when a user has made an item * unselected. The event_info parameter is the genlist item that was * unselected. * - @c "expanded" - This is called when elm_genlist_item_expanded_set() is * called and the item is now meant to be expanded. The event_info * parameter is the genlist item that was indicated to expand. It is the * job of this callback to then fill in the child items. * - @c "contracted" - This is called when elm_genlist_item_expanded_set() is * called and the item is now meant to be contracted. The event_info * parameter is the genlist item that was indicated to contract. It is the * job of this callback to then delete the child items. * - @c "expand,request" - This is called when a user has indicated they want * to expand a tree branch item. The callback should decide if the item can * expand (has any children) and then call elm_genlist_item_expanded_set() * appropriately to set the state. The event_info parameter is the genlist * item that was indicated to expand. * - @c "contract,request" - This is called when a user has indicated they * want to contract a tree branch item. The callback should decide if the * item can contract (has any children) and then call * elm_genlist_item_expanded_set() appropriately to set the state. The * event_info parameter is the genlist item that was indicated to contract. * - @c "realized" - This is called when the item in the list is created as a * real evas object. event_info parameter is the genlist item that was * created. * - @c "unrealized" - This is called just before an item is unrealized. * After this call content objects provided will be deleted and the item * object itself delete or be put into a floating cache. * - @c "drag,start,up" - This is called when the item in the list has been * dragged (not scrolled) up. * - @c "drag,start,down" - This is called when the item in the list has been * dragged (not scrolled) down. * - @c "drag,start,left" - This is called when the item in the list has been * dragged (not scrolled) left. * - @c "drag,start,right" - This is called when the item in the list has * been dragged (not scrolled) right. * - @c "drag,stop" - This is called when the item in the list has stopped * being dragged. * - @c "drag" - This is called when the item in the list is being dragged. * - @c "longpressed" - This is called when the item is pressed for a certain * amount of time. By default it's 1 second. The event_info parameter is the * longpressed genlist item. * - @c "scroll" - the content has been scrolled (moved) (since 1.13) * - @c "scroll,anim,start" - This is called when scrolling animation has * started. * - @c "scroll,anim,stop" - This is called when scrolling animation has * stopped. * - @c "scroll,drag,start" - This is called when dragging the content has * started. * - @c "scroll,drag,stop" - This is called when dragging the content has * stopped. * - @c "edge,top" - This is called when the genlist is scrolled until * the top edge. * - @c "edge,bottom" - This is called when the genlist is scrolled * until the bottom edge. * - @c "edge,left" - This is called when the genlist is scrolled * until the left edge. * - @c "edge,right" - This is called when the genlist is scrolled * until the right edge. * - @c "multi,swipe,left" - This is called when the genlist is multi-touch * swiped left. * - @c "multi,swipe,right" - This is called when the genlist is multi-touch * swiped right. * - @c "multi,swipe,up" - This is called when the genlist is multi-touch * swiped up. * - @c "multi,swipe,down" - This is called when the genlist is multi-touch * swiped down. * - @c "multi,pinch,out" - This is called when the genlist is multi-touch * pinched out. * - @c "multi,pinch,in" - This is called when the genlist is multi-touch * pinched in. * - @c "swipe" - This is called when the genlist is swiped. * - @c "moved" - This is called when a genlist item is moved by a user * interaction in a reorder mode. The @p event_info parameter is the item that * was moved. * - @c "moved,after" - This is called when a genlist item is moved after * another item in reorder mode. The event_info parameter is the reordered * item. To get the relative previous item, use elm_genlist_item_prev_get(). * This signal is called along with "moved" signal. * - @c "moved,before" - This is called when a genlist item is moved before * another item in reorder mode. The event_info parameter is the reordered * item. To get the relative previous item, use elm_genlist_item_next_get(). * This signal is called along with "moved" signal. * - @c "index,update" - This is called when a genlist item index is changed. * Note that this callback is called while each item is being realized. * - @c "language,changed" - This is called when the program's language is * changed. Call the elm_genlist_realized_items_update() if items text should * be translated. * - @c "tree,effect,finished" - This is called when a genlist tree effect is finished. * - @c "highlighted" - an item in the list is highlighted. This is called when * the user presses an item or keyboard selection is done so the item is * physically highlighted. The @p event_info parameter is the item that was * highlighted. * - @c "unhighlighted" - an item in the list is unhighlighted. This is called * when the user releases an item or keyboard selection is moved so the item * is physically unhighlighted. The @p event_info parameter is the item that * was unhighlighted. * - @c "focused" - When the genlist has received focus. (since 1.8) * - @c "unfocused" - When the genlist has lost focus. (since 1.8) * - @c "item,focused" - When the genlist item has received focus. (since 1.10) * - @c "item,unfocused" - When the genlist item has lost focus. (since 1.10) * * * Supported elm_object_item common APIs * @li @ref elm_object_item_part_content_get * @li @ref elm_object_item_part_text_get * @li @ref elm_object_item_disabled_set * @li @ref elm_object_item_disabled_get * @li @ref elm_object_item_signal_emit * * Unsupported elm_object_item common APIs due to the genlist concept. * Genlist fills content/text according to the appropriate callback functions. * Please use elm_genlist_item_update() or elm_genlist_item_fields_update() * instead. * @li @ref elm_object_item_part_content_set * @li @ref elm_object_item_part_content_unset * @li @ref elm_object_item_part_text_set * * @section Genlist_Examples Examples * * Here is a list of examples that use the genlist, trying to show some of * its capabilities: * - @ref genlist_example_01 * - @ref genlist_example_02 * - @ref genlist_example_03 * - @ref genlist_example_04 * - @ref genlist_example_05 */ /** * @addtogroup Elm_Genlist * @{ */ #include #ifndef EFL_NOLEGACY_API_SUPPORT #include #endif /** * @} */