NotificationManager QML Type
The notification model, which handles freedesktop.org compliant notification requests. More...
| Import Statement: | import QtApplicationManager.SystemUI |
Properties
- count : int
Signals
- notificationAboutToBeRemoved(uint id)
- notificationAdded(uint id)
- notificationChanged(uint id, list<string> changedRoles)
Methods
- void acknowledgeNotification(int id)
- void dismissNotification(int id)
- object get(int index)
- int indexOfNotification(int id)
- object notification(int id)
- void triggerNotificationAction(int id, string actionId)
Detailed Description
The NotificationManager singleton type provides a QML API only.
The type is derived from QAbstractListModel and can be directly used as a model in notification views.
Each item in this model corresponds to an active notification.
Applications create individual notifications via the Notification type; NotificationManager is the System-UI-side aggregator and model for all of them.
NotificationManager Limits
To protect the System UI from flooding (whether accidental - an app stuck in a notification loop - or adversarial), the NotificationManager enforces two caps on the number of simultaneously active notifications:
- Per-application cap: at most 50 notifications per application id. Once this is reached, further notification requests from that application are rejected with a warning in the log.
- Global cap: at most 500 active notifications across all sources. When the global cap is reached and a new notification is requested, the oldest non-sticky notification is evicted to make room. Sticky notifications (those with
timeoutset to0) are protected from eviction. If the global cap is reached and all active notifications are sticky, the new request is rejected.
The per-application cap is tied to the applicationId. Notifications from different sources therefore cannot crowd each other out.
These limits match the behavior of major mobile platforms.
NotificationManager Roles
The following roles are available in this model - also take a look at the freedesktop.org specification for an in-depth explanation of these fields and how clients should populate them:
| Role name | Type | Description |
|---|---|---|
id | int | The unique id of this notification. |
applicationId | string | The id of the application that created this notification. This can be used to look up information about the application in the ApplicationManager model. Note: The Note: Notifications coming in via the external |
priority | int | See the client side documentation of Notification::priority |
summary | string | See the client side documentation of Notification::summary |
body | string | See the client side documentation of Notification::body |
category | string | See the client side documentation of Notification::category |
icon | url | See the client side documentation of Notification::icon |
image | url | See the client side documentation of Notification::image |
actions | object | See the client side documentation of Notification::actions. This is a list where each item is a single property (the key is the actionId and the value the actionText). Easier access is provided with the actionList role below. |
actionList | object | See the client side documentation of Notification::actions. In contrast to the actions object above actions are provided as a list with actionId and actionText properties |
showActionsAsIcons | bool | See the client side documentation of Notification::showActionsAsIcons |
dismissOnAction | bool | See the client side documentation of Notification::dismissOnAction |
isAcknowledgeable | bool | See the client side documentation of Notification::acknowledgeable For backwards compatibility, isClickable can also be used to refer to this role. |
isSystemNotification | bool | Holds true for notifications coming in via the external org.freedesktop.Notifications D-Bus interface and false for notifications coming from integrated applications or the System UI. |
isShowingProgress | bool | See the client side documentation of Notification::showProgress |
progress | qreal | See the client side documentation of Notification::progress |
isSticky | bool | See the client side documentation of Notification::sticky |
timeout | int | See the client side documentation of Notification::timeout |
extended | object | See the client side documentation of Notification::extended |
created | date | The timestamp denoting when the notification was created |
updated | date | The timestamp denoting when the notification was last modififed |
The actual backend implementation that is receiving the notifications from other process is fully compliant to the D-Bus interface of the freedesktop.org specification for notifications.
For testing purposes, the notify-send tool from the libnotify package can be used to create notifications.
See also Notification.
Property Documentation
count : int [read-only]
This property holds the number of active notifications in the model.
Signal Documentation
notificationAboutToBeRemoved(uint id)
This signal is emitted before an existing notification, identified by id, is removed from the model.
Note: In addition to the normal "low-level" QAbstractListModel signals, the application manager will also emit these "high-level" signals for System UIs that cannot work directly on the NotificationManager model: notificationAdded, notificationAboutToBeRemoved and notificationChanged.
Note: The corresponding handler is onNotificationAboutToBeRemoved.
notificationAdded(uint id)
This signal is emitted after a new notification, identified by id, has been added. The model has already been update before this signal is sent out.
Note: In addition to the normal "low-level" QAbstractListModel signals, the application manager will also emit these "high-level" signals for System UIs that cannot work directly on the NotificationManager model: notificationAdded, notificationAboutToBeRemoved and notificationChanged.
Note: The corresponding handler is onNotificationAdded.
notificationChanged(uint id, list<string> changedRoles)
Emitted whenever one or more data roles, denoted by changedRoles, changed on the notification identified by id. An empty list in the changedRoles argument means that all roles should be considered modified.
Note: In addition to the normal "low-level" QAbstractListModel signals, the application manager will also emit these "high-level" signals for System UIs that cannot work directly on the NotificationManager model: notificationAdded, notificationAboutToBeRemoved and notificationChanged.
Note: The corresponding handler is onNotificationChanged.
Method Documentation
void acknowledgeNotification(int id)
This function needs to be called by the System UI when the user acknowledged the notification identified by id (most likely by clicking on it).
void dismissNotification(int id)
This function needs to be called by the System UI when the notification identified by id is no longer needed.
The creator of the notification will be notified about this dismissal.
object get(int index)
Retrieves the model data at index as a JavaScript object. See the role names for the expected object fields.
Returns an empty object if the specified index is invalid.
int indexOfNotification(int id)
Maps the notification id to its position within the model.
Returns -1 if the specified id is invalid.
object notification(int id)
Retrieves the model data for the notification identified by id as a JavaScript object. See the role names for the expected object fields.
Returns an empty object if the specified id is invalid.
void triggerNotificationAction(int id, string actionId)
This function needs to be called by the System UI when the user triggered a notification action. Unless the notification is made resident (dismissOnAction is false), the notification will also be dismissed.
The notification is identified by id and the action by actionId.
Note: You should only use action-ids that have been set for the the given notification (see the actions role). However, the application manager will accept and forward any arbitrary string. Be aware that this string is broadcast on the session D-Bus when running in multi-process mode.
See also dismissNotification().
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