Basics
User interface
The following uses Qt terminology for modifier key names. The following table shows the mapping of modifier keys on different keyboards:
| Qt | Linux/Win | MacOS |
|---|---|---|
| Ctrl | Ctrl | command /⌘ |
| Meta | Win | control /⌃ |
| Alt | Alt | option /⌥ |
Besides its primary function, the input line displays the input action text and input hint and contains the settings button.
If available the input action text will be displayed right beside your input. It is provided by the currently selected item in the results list. Its semantics are loosely defined; it may be a completion, an evaluation, or something else. Hit Tab to replace the current input with this text.
If space permits, the input hint will be displayed right-aligned in the input box. It serves as a reminder for hard-to-remember synopses.
The settings button is located in the top-right corner of the input line.
It appears on mouse hover and also serves as a busy indicator, e.g., when a query is being processed.
Left-clicking opens the settings window, while right-clicking shows a context menu.
The manually entered text of the input line is stored in the input history when the window is hidden. This input history can be used to search and browse your past input. When the results list is hidden or the first item is selected ⬆ iterates the input history in reverse order. Holding Shift enables input history navigation for ⬆ and ⬇ no matter which item is selected.
If enabled, the (manually set) input text is used for input history search. Input history navigation then only shows input history entries matching the input text.
The results list displays result items of a query. Hold and release Meta to switch between match items and fallback items.
Result items can have multiple associated actions. The default action of an item is activated by pressing Return or Enter. To display and navigate the list of alternative actions of an item hold Alt .
Key map
As a reference the following table lists the keys you can use to control Albert:
| Key | Action |
|---|---|
| Esc | Hide the window. |
| Alt (Hold) Ctrl+Return | Show actions. |
| Meta (Hold) | Show fallbacks. |
| Shift+⬆ | Next entry in input history. |
| Shift+⬇ | Previous entry in input history. |
| Tab | Activate input action of the selected item (evaluation, completion, etc). |
| Return,Ctrl+O | Activate item. |
| Shift+Return | Insert new line. |
| Ctrl+Shift+Return Ctrl+Shift+O | Activate item but do not hide. |
| Ctrl+, | Open settings window. |
| ⬆,⬇, PgUp,PgDn | Navigation in item lists. |
| Alt+F4,⌘+Q | Quit Albert (Depends on settings). |
| Ctrl+H/J/K/L | Vim bindings. Synthesize to arrows. |
| Ctrl+N/P | Emacs bindings. Synthesize to arrows. |
Plugins and extensions
A plugin is a physical module that can be loaded/unloaded at runtime. It could be native or provided by plugin provider plugins. Nested plugins are accessible when their provider is loaded.
Users can enable/disable or load/unload plugins via the plugins tab in the settings or using the built-in plugin query handler. Enabled plugins load automatically at launch. Plugins with graphical interfaces for configuration can be accessed via the plugins tab in the settings.
An extension is a logical module that can be used to add functionality to the app. Each plugin can provide multiple extension implementations or even expose its own extension interfaces. More on this topic can be found in the Extension section
Queries
The core of the app is the query engine which parses user input and determines the mode of a query.
If the input starts with a trigger of a trigger query handler, the query engine instantiates a trigger query execution that is exclusively handled by the corresponding handler. This allows the handler to asynchronously add matches and as such define their order.
If the user input does not start with a trigger of a trigger query handler, the query engine instantiates a global query execution that executes the enabled global query handlers in parallel and eventually gathers and sorts their matches.
Both query executions eventually yield a set of query matches which may be empty.
The fallback handlers of a query provide a separate set of result items, the query fallbacks, which can handle any string. They are displayed when no matches were found or when the user explicitly requests them.