AbstractRunner Class Reference
from PyKDE4.plasma import *
Inherits: QObject
Namespace: Plasma
Detailed Description
AbstractRunner plasma/abstractrunner.h <Plasma/AbstractRunner>
An abstract base class for Plasma Runner plugins.
Be aware that runners have to be thread-safe. This is due to the fact that each runner is executed in its own thread for each new term. Thus, a runner may be executed more than once at the same time. See match() for details. To let krunner expose a global shortcut for the single runner query mode, the runner must set the "X-Plasma-AdvertiseSingleRunnerMode" key to true in the .desktop file and set a default syntax. See setDefaultSyntax() for details.
Signal Documentation
prepare | ( | ) |
This signal is emitted when matching is about to commence, giving runners an opportunity to prepare themselves, e.g. loading data sets or preparing IPC or network connections. This method should be fast so as not to cause slow downs. Things that take longer or which should be loaded once and remain extant for the lifespan of the AbstractRunner should be done in init().
- See also:
- init()
- Since:
- 4.4
- Signal syntax:
QObject.connect(source, SIGNAL("prepare()"), target_slot)
teardown | ( | ) |
This signal is emitted when a session of matches is complete, giving runners the opportunity to tear down anything set up as a result of the prepare() method.
- Since:
- 4.4
- Signal syntax:
QObject.connect(source, SIGNAL("teardown()"), target_slot)
Method Documentation
__init__ | ( | self, | ||
KSharedPtr |
service, | |||
QObject | parent=0 | |||
) |
[QAction] actionsForMatch | ( | self, | ||
Plasma.QueryMatch | match | |||
) |
A given match can have more than action that can be performed on it. For example, a song match returned by a music player runner can be queued, added to the playlist, or played.
Call this method to add actions that can be performed by the runner. Actions must first be added to the runner's action registry. Note: execution of correct action is left up to the runner.
Adds an action to the runner's action registry.
The QAction must be created within the GUI thread; do not create it within the match method of AbstractRunner.
- Parameters:
-
id A unique identifier string action The QAction to be stored
Adds an action to the runner's action registry.
The QAction must be created within the GUI thread; do not create it within the match method of AbstractRunner.
- Parameters:
-
id A unique identifier string action The QAction to be stored
addSyntax | ( | self, | ||
Plasma.RunnerSyntax | syntax | |||
) |
Adds a registered syntax that this runner understands. This is used to display to the user what this runner can understand and how it can be used.
- Parameters:
-
syntax the syntax to register
- Since:
- 4.3
clearActions | ( | self ) |
Clears the action registry. The action pool deletes the actions.
KConfigGroup config | ( | self ) |
Provides access to the runner's configuration object.
createRunOptions | ( | self, | ||
QWidget | widget | |||
) |
If hasRunOptions() returns true, this method may be called to get a widget displaying the options the user can interact with to modify the behaviour of what happens when a given match is selected.
- Parameters:
-
widget the parent of the options widgets.
Plasma.DataEngine dataEngine | ( | self, | ||
QString | name | |||
) |
Loads the given DataEngine
Tries to load the data engine given by name. Each engine is only loaded once, and that instance is re-used on all subsequent requests.
If the data engine was not found, an invalid data engine is returned (see DataEngine.isValid()).
Note that you should <em>not</em> delete the returned engine.
- Parameters:
-
name Name of the data engine to load
- Returns:
- pointer to the data engine if it was loaded, or an invalid data engine if the requested engine could not be loaded
- Since:
- 4.4
Plasma.RunnerSyntax defaultSyntax | ( | self ) |
- Returns:
- the default syntax for the runner or 0 if no default syntax has been defined
- Since:
- 4.4
QString description | ( | self ) |
- Returns:
- the description of this Runner
bool hasRunOptions | ( | self ) |
If the runner has options that the user can interact with to modify what happens when run or one of the actions created in match is called, the runner should return true
QIcon icon | ( | self ) |
- Returns:
- the icon for this Runner
QString id | ( | self ) |
- Returns:
- an id string for the Runner
Plasma.RunnerContext.Types ignoredTypes | ( | self ) |
Returns the OR'ed value of all the Information types (as defined in RunnerContext.Type) this runner is not interested in.
- Returns:
- OR'ed value of black listed types
init | ( | self ) |
match | ( | self, | ||
Plasma.RunnerContext | context | |||
) |
This is the main query method. It should trigger creation of QueryMatch instances through RunnerContext.addMatch and RunnerContext.addMatches. It is called internally by performMatch().
If the runner can run precisely the requested term (RunnerContext.query()), it should create an exact match by setting the type to RunnerContext.ExactMatch. The first runner that creates a QueryMatch will be the default runner. Other runner's matches will be suggested in the interface. Non-exact matches should be offered via RunnerContext.PossibleMatch.
The match will be activated via run() if the user selects it.
Each runner is executed in its own thread. Whenever the user input changes this method is called again. Thus, it needs to be thread-safe. Also, all matches need to be reported once this method returns. Asyncroneous runners therefore need to make use of a local event loop to wait for all matches.
It is recommended to use local status data in async runners. The simplest way is to have a separate class doing all the work like so:
void MyFancyAsyncRunner.match( RunnerContext& context ) { QEventLoop loop; MyAsyncWorker worker( context ); connect( &worker, SIGNAL(finished()), &loop, SLOT(quit()) ); worker.work(); loop.exec(); }
Here MyAsyncWorker creates all the matches and calls RunnerContext.addMatch in some internal slot. It emits the finished() signal once done which will quit the loop and make the match() method return. The local status is kept entirely in MyAsyncWorker which makes match() trivially thread-safe.
If a particular match supports multiple actions, set up the corresponding actions in the actionsForMatch method. Do not call any of the action methods within this method!
Execution of the correct action should be handled in the run method. @caution This method needs to be thread-safe since KRunner will simply start a new thread for each new term.
- Warning:
- Returning from this method means to end execution of the runner.
@sa run(), RunnerContext.addMatch, RunnerContext.addMatches, QueryMatch
QMimeData mimeDataForMatch | ( | self, | ||
Plasma.QueryMatch | match | |||
) |
Reimplement this slot if you want your runner to support serialization and drag and drop
- Since:
- 4.5
QString name | ( | self ) |
- Returns:
- the user visible engine name for the Runner
Plasma.Package package | ( | self ) |
Accessor for the associated Package object if any.
Note that the returned pointer is only valid for the lifetime of the runner.
- Returns:
- the Package object, or 0 if none
performMatch | ( | self, | ||
Plasma.RunnerContext | context | |||
) |
Triggers a call to match. This will call match() internally.
@arg context the search context used in executing this match.
Plasma.AbstractRunner.Priority priority | ( | self ) |
The priority of the runner.
- See also:
- setPriority
reloadConfiguration | ( | self ) |
Signal runner to reload its configuration.
removeAction | ( | self, | ||
QString | id | |||
) |
Removes the action from the action registry. AbstractRunner deletes the action once removed.
- Parameters:
-
id The id of the action to be removed
run | ( | self, | ||
Plasma.RunnerContext | context, | |||
Plasma.QueryMatch | match | |||
) |
Called whenever an exact or possible match associated with this runner is triggered.
- Parameters:
-
context The context in which the match is triggered, i.e. for which the match was created. match The actual match to run/execute.
- Deprecated:
- A blocking method to do queries of installed Services which can provide a measure of safety for runners running their own threads. This should be used instead of calling KServiceTypeTrader.query(..) directly.
@arg serviceType a service type like "Plasma/Applet" or "KFilePlugin" @arg constraint a constraint to limit the choices returned.
- See also:
- KServiceTypeTrader.query(const QString&, const QString&)
- Returns:
- a list of services that satisfy the query.
setDefaultSyntax | ( | self, | ||
Plasma.RunnerSyntax | syntax | |||
) |
Set syntax as the default syntax for the runner; the default syntax will be substituted to the empty query in single runner mode. This is also used to display to the user what this runner can understand and how it can be used. The default syntax is automatically added to the list of registered syntaxes, there is no need to add it using addSyntax. Note that there can be only one default syntax; if called more than once, the last call will determine the default syntax. A default syntax (even trivial) is required to advertise single runner mode
- Parameters:
-
syntax the syntax to register and to set as default
- Since:
- 4.4
setHasRunOptions | ( | self, | ||
bool | hasRunOptions | |||
) |
Sets whether or not the runner has options for matches
setIgnoredTypes | ( | self, | ||
Plasma.RunnerContext.Types | types | |||
) |
Sets the types this runner will ignore
- Parameters:
-
types OR'ed listed of ignored types
setPriority | ( | self, | ||
Plasma.AbstractRunner.Priority | newPriority | |||
) |
Sets the priority of the runner. Lower priority runners are executed only after higher priority runners.
setSpeed | ( | self, | ||
Plasma.AbstractRunner.Speed | newSpeed | |||
) |
Sets the nominal speed of the runner. Only slow runners need to call this within their constructor because the default speed is NormalSpeed. Runners that use DBUS should call this within their constructors.
setSyntaxes | ( | self, | ||
[Plasma.RunnerSyntax] | syns | |||
) |
Sets the list of syntaxes; passing in an empty list effectively clears the syntaxes.
- Parameters:
-
the syntaxes to register for this runner
- Since:
- 4.3
Plasma.AbstractRunner.Speed speed | ( | self ) |
The nominal speed of the runner.
- See also:
- setSpeed
[Plasma.RunnerSyntax] syntaxes | ( | self ) |
- Returns:
- the syntaxes the runner has registered that it accepts and understands
- Since:
- 4.3
Static Method Documentation
QMutex bigLock | ( | ) |
Access to a shared lock that all runners (and code that manages/interacts with them) can share to protect access to non-thread-safe shared code or data. Access of KSycoca records, for instance, is one place this lock should be used.
Common usage:
{ QMutexLocker lock(bigLock()); .. do something that isn't thread safe .. }
Enumeration Documentation
Priority |
Specifies a priority for the runner
- Enumerator:
-
LowestPriority = 0 LowPriority NormalPriority HighPriority HighestPriority
Speed |
Specifies a nominal speed for the runner
- Enumerator:
-
SlowSpeed NormalSpeed