TaurusBaseComponent

Inheritance diagram of TaurusBaseComponent
class TaurusBaseComponent(name='', parent=None, designMode=False, **kwargs)[source]

A generic Taurus component.

Note

Any class which inherits from TaurusBaseComponent is expected to also inherit from QObject (or from a QObject derived class).

Note

getSignaller() is now unused and deprecated. This is because taurusEvent is implemented using baseSignal(), that doesn’t require the class to inherit from QObject.

Import from taurus.qt.qtgui.base as:

from taurus.qt.qtgui.base import TaurusBaseComponent
FORMAT = None
MLIST = 0

MLIST is a constant that can be passed as the value of the key kwarg in the multi-model API to indicate that the class should act as a model-container regarding to this key (e.g. TaurusBaseComponent.setModel(m, key=MLIST) will treat m as a list of models.

applyPendingOperations(ops=None)[source]

Applies operations without caring about danger messages. Use TaurusBaseWidget.safeApplyOperation() if you want to warn the user before applying

Parameters

ops (sequence<taurus.core.taurusoperation.TaurusOperation> or None) – list of operations to apply. If None is given (default) the component fetches the pending operations

contextMenuEvent(event)[source]

DEPRECATED: Until v4.5.3a, the default implementation of contextMenuEvent showed the content of taurusMenu as a context menu. But this resulted in unwanted behaviour when the widget already implemented its own context menu (see https://gitlab.com/taurus-org/taurus/-/issues/905 )

Therefore this feature was disabled in 4.5.3a.

If you still want to show the contents of taurusMenu as a context menu, you can explicitly reimplement the contextMenuEvent method as:

def contextMenuEvent(self, event):
    self.taurusMenu.exec_(event.globalPos())
defaultFormatDict = {<class 'float'>: '{:.{bc.modelObj.precision}f}', <enum 'Enum'>: '{0.name}', <class 'pint.quantity.build_quantity_class.<locals>.Quantity'>: '{:~.{bc.modelObj.precision}f}'}
deleteLater()[source]

Reimplements the Qt.QObject deleteLater method to ensure that the this object stops listening its model.

displayValue(v)[source]

Returns a string representation of the given value

This method will use a format string which is determined dynamically from FORMAT.

By default TaurusBaseComponent.FORMAT is set to defaultFormatter(), which makes use of defaultFormatDict.

In order to customize the formatting behaviour, one can use setFormat() to alter the formatter of an specific instance (recommended) or change defaultFormatDict or FORMAT directly at class level.

The formatter can be set to a python format string [1] or a callable that returns a python format string. If a callable is used, it will be called with the following keyword arguments:

  • dtype: the data type of the value to be formatted

  • basecomponent: the affected widget

The following are some examples for customizing the formatting:

- Change the format for widget instance `foo`::

foo.setFormat(“{:.2e}”)

  • Change FORMAT for all widgets (using a string):

    TaurusBaseComponent.FORMAT = "{:.2e}"
    
  • Change FORMAT for all TaurusLabels (using a callable):

    def baseFormatter(dtype=None, basecomponent=None, **kwargs):
        return "{:.1f}"
    
    TaurusLabel.FORMAT = baseFormatter
    
  • Use the defaultFormatDict but modify the format string for dtype=str:

    TaurusLabel.defaultFormatDict.update({"str": "{!r}"})
    

See also

tauruscustomsettings.DEFAULT_FORMATTER, –default-formatter option in TaurusApplication, TaurusBaseWidget.onSetFormatter()

[1] https://docs.python.org/2/library/string.html

Parameters

v (object) – the value to be translated to string

Returns

a string representing the given value

Return type

str

eventReceived(evt_src, evt_type, evt_value)[source]

The basic implementation of the event handling chain is as follows:

Note

in the earlier steps of the chain (i.e., in eventReceived()/ fireEvent()), the code is executed in a Python thread, while from eventFilter ahead, the code is executed in a Qt thread. When writing widgets, one should normally work on the Qt thread (i.e. reimplementing handleEvent())

Parameters
  • evt_src (object) – object that triggered the event

  • evt_type (taurus.core.taurusbasetypes.TaurusEventType) – type of event

  • evt_value (object) – event value

filterEvent(evt_src=- 1, evt_type=- 1, evt_value=- 1)[source]

The event is processed by each and all filters in strict order unless one of them returns None (in which case the event is discarded)

Parameters
  • evt_src (object) – object that triggered the event

  • evt_type (taurus.core.taurusbasetypes.TaurusEventType) – type of event

  • evt_value (object) – event value

findModelClass(**kwargs)

Deprecated since version 5.1.0: Use getModelClass instead

fireBufferedEvents()[source]

Fire all events currently buffered (and flush the buffer)

Note: this method is normally called from an event buffer timer thread

but it can also be called any time the buffer needs to be flushed

fireEvent(evt_src=None, evt_type=None, evt_value=None)[source]

Emits a “taurusEvent” signal. It is unlikely that you need to reimplement this method in subclasses. Consider reimplementing eventReceived() or handleEvent() instead depending on whether you need to execute code in the python or Qt threads, respectively

Parameters
  • evt_src (object or None) – object that triggered the event

  • evt_type (taurus.core.taurusbasetypes.TaurusEventType or None) – type of event

  • evt_value (object or None) – event value

getDangerMessage()[source]

Returns the current apply danger message or None if the apply operation is safe

Returns

the apply danger message

Return type

str or None

getDisplayValue(cache=True, fragmentName=None, *, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns a string representation of the model value associated with this component.

Parameters
  • cache (bool) – (ignored, just for bck-compat).

  • fragmentName (str or None) – the returned value will correspond to the given fragmentName. If None passed, self.modelFragmentName will be used, and if None is set, the defaultFragmentName of the model will be used instead.

  • key (object) – the model key. Defaults to first element of .modelKeys

Returns

a string representation of the model value.

Return type

str

getEventBufferPeriod()[source]

Returns the event buffer period

Returns

period (in s). 0 means event buffering is disabled.

Return type

float

getEventFilters(preqt=False)[source]

Returns the list of event filters for this widget

Parameters

preqt (bool) – If true, return the pre-filters (that are applied in eventReceived, at the python thread), otherwise, return the filters to be applied at the main Qt thread (default)

Returns

the event filters

Return type

sequence<callable>

getForceDangerousOperations()[source]

Returns if apply dangerous operations is forced

Returns

wheter or not apply dangerous operations is forced

Return type

bool

getFormat()[source]

Method to get the FORMAT attribute for this instance.

Returns

a string of the current format. It could be a python format string or a callable string representation.

Return type

str

getFormatedToolTip(cache=True)[source]

Returns a string with contents to be displayed in a tooltip.

Parameters

cache (bool) – if set to True (default) use the cache value. If set to False will force a connection to the server.

Returns

a tooltip

Return type

str

getFullModelName(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the full name of the model object for the given key.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

the model name

Return type

str

getModel(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the model name for this component.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

the model name.

Return type

str

getModelClass(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Return the class object for the widget. Default behavior is to do a ‘best effort’ to determine which model type corresponds to the current model name. Overwrite as necessary.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

The class object corresponding to the type of Taurus model this widget handles or None if no valid class is found.

Return type

class TaurusModel or None

getModelFragmentObj(fragmentName=None, *, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns a fragment object of the model. A fragment of a model is a python attribute of the model object.

Fragment names including dots will be used to recursively get fragments of fragments.

For a simple fragmentName (no dots), this is roughly equivalent to getattr(self.getModelObj(), fragmentName)

If the model does not have that fragment, AttributeError is raised (other exceptions may be raised when accessing the fragment as well)

Parameters
  • fragmentName (str or None) – the returned value will correspond to the given fragmentName. If None passed, self.modelFragmentName will be used, and if None is set, the defaultFragmentName of the model will be used instead.

  • key (object) – the model key. Defaults to first element of .modelKeys

Returns

the member of the modelObj referred by the fragment.

Return type

obj

getModelInConfig()[source]
getModelIndexValue()[source]

Called inside getDisplayValue to use with spectrum attributes. By default not used, but some widget might want to support this feature.

Note

getModelIndexValue() is only supported for the default model key

Override when needed.

getModelName(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the current model name.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

the model name

Return type

str

getModelNames()[source]

Returns a dict of key:modelname

Returns

dictionary mapping keys to model names

Return type

dict

getModelObj(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the taurus model object associated to the given key or None if no taurus model is associated.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

the taurus model object

Return type

taurus.core.taurusmodel.TaurusModel or None

getModelType(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the taurus model type associated with this key or taurus.core.taurusbasetypes.TaurusElementType.Unknown if no taurus model is associated.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

the taurus model type

Return type

taurus.core.taurusbasetypes.TaurusElementType

getModelValueObj(cache=True, *, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Returns the current value of the taurus model associated with this key or None if no taurus model is associated.

Parameters
  • cache (bool) – if set to True (default) use the cache value. If set to False will force a connection to the server.

  • key (object) – the model key. Defaults to first element of .modelKeys

Returns

the tango value object.

Return type

TaurusAttrValue

getNoneValue()[source]

Returns the current string representation when no valid model or model value exists.

Returns

a string representation for an invalid value

Return type

str

getParentModelName(**kwargs)

Deprecated since version 4.3.2.

getParentModelObj(**kwargs)

Deprecated since version 4.3.2.

getParentTaurusComponent(**kwargs)

Deprecated since version 4.3.2.

getPendingOperations()[source]

Returns the sequence of pending operations

Returns

a list of pending operations

Return type

sequence<taurus.core.taurusoperation.TaurusOperation>

getShowQuality()[source]

Returns if showing the quality as a background color

Returns

True if showing the quality or False otherwise

Return type

bool

getShowText()[source]

Returns if showing the display value

Returns

True if showing the display value or False otherwise

Return type

bool

getSignaller(**kwargs)

Deprecated since version 4.0.

getTaurusFactory(scheme='')[source]

Returns the taurus factory singleton for the given scheme. This is just a helper method. It is the equivalent of doing:

import taurus
factory = taurus.Factory(scheme)
Parameters

scheme (str or None) – the scheme. If scheme is an empty string, or is not passed, the scheme will be obtained from the model name. For backwards compatibility (but deprecated), passing None is equivalent to ‘tango’.

Returns

the TaurusFactory

Return type

taurus.core.taurusfactory.TaurusFactory

getTaurusManager()[source]

Returns the taurus manager singleton. This is just a helper method. It is the equivalent of doing:

import taurus
manager = taurus.Manager()
Returns

the TaurusManager

Return type

taurus.core.taurusmanager.TaurusManager

getTaurusPopupMenu(**kwargs)

Returns an xml string representing the current taurus popup menu

return

an xml string representing the current taurus popup menu

rtype

str

Deprecated since version 4.5.3a.

getUseParentModel(**kwargs)

Deprecated since version 4.3.2.

static get_registered_formatters()[source]

Static method to get the registered formatters :return: dict of registered formatter (keys are the registered names) :rtype: dict

handleEvent(evt_src, evt_type, evt_value)[source]

Event handling. Default implementation does nothing. Reimplement as necessary

Parameters
  • evt_src (object or None) – object that triggered the event

  • evt_type (taurus.core.taurusbasetypes.TaurusEventType or None) – type of event

  • evt_value (object or None) – event value

hasPendingOperations()[source]

Returns if the component has pending operations

Returns

True if there are pending operations or False otherwise

Return type

bool

insertEventFilter(filter, index=- 1, preqt=False)[source]

insert a filter in a given position

Parameters
  • filter (callable(evt_src, evt_type, evt_value) – ) a filter

  • index (int) – index to place the filter (default = -1 meaning place at the end)

  • preqt (bool) – If true, set the pre-filters (that are applied in eventReceived, at the python thread), otherwise, set the filters to be applied at the main Qt thread (default)

See also: setEventFilters

isAttached(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Determines if this component is attached to the taurus model.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

Returns

True if the component is attached or False otherwise.

Return type

bool

isAutoProtectOperation()[source]

Tells if this widget’s operations are protected against exceptions

Returns

True if operations are protected against exceptions or False otherwise

Return type

bool

isChangeable()[source]

Tells if this component value can be changed by the user. Default implementation will return True if and only if:

  • this component is attached to a valid taurus model and

  • the taurus model is writable and

  • this component is not read-only

Returns

True if this component value can be changed by the user or False otherwise

Return type

bool

isDangerous()[source]

Returns if the apply operation for this component is dangerous

Returns

wheter or not the apply operation for this component is dangerous

Return type

bool

isModifiableByUser()[source]

whether the user can change the contents of the widget

Returns

True if the user is allowed to modify the look&feel

Return type

bool

isPaused()[source]

Return the current pause state

Returns

wheater or not the widget is paused

Return type

bool

isReadOnly()[source]

Determines if this component is read-only or not in the sense that the user can interact with it. Default implementation returns True.

Override when necessary.

Returns

whether or not this component is read-only

Return type

bool

property modelFragmentName
modelKeys = ['']
property modelName
property modelObj
postAttach(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Called inside self.attach() after actual attach is performed. Default implementation does not do anything.

Override when necessary.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

postDetach(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Called inside self.detach() after actual deattach is performed. Default implementation does not do anything.

Override when necessary.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

preAttach(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Called inside self.attach() before actual attach is performed. Default implementation does nothing.

Override when necessary.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

preDetach(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Called inside self.detach() before actual deattach is performed. Default implementation does nothing.

Override when necessary.

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

resetAutoProtectOperation()[source]

Resets protecting operations

resetDangerMessage()[source]

Clears the danger message. After this method is executed the apply operation for this component will be considered safe.

resetForceDangerousOperations()[source]

Clears forcing apply dangerous operations

resetFormat()[source]

Reset the internal format string. It forces a recalculation in the next call to displayValue().

resetModel(*, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Sets the model name to the empty string

Parameters

key (object) – the model key. Defaults to first element of .modelKeys

resetModelInConfig()[source]
resetModifiableByUser()[source]

Equivalent to setModifiableByUser(self.__class__._modifiableByUser)

resetPendingOperations()[source]

Clears the list of pending operations

resetShowQuality()[source]

Resets the show quality to self.__class__._showQuality

resetShowText()[source]

Resets the showing of the display value to True

resetTaurusPopupMenu(**kwargs)

Resets the taurus popup menu to empty

Deprecated since version 4.5.3a.

resetUseParentModel(**kwargs)

Deprecated since version 4.3.2.

setAutoProtectOperation(protect)[source]

Sets/unsets this widget’s operations are protected against exceptions

Parameters

protect (bool) – wheater or not to protect widget operations

setDangerMessage(dangerMessage='')[source]

Sets the danger message when applying an operation. If dangerMessage is None, the apply operation is considered safe

Parameters

dangerMessage (str or None) – the danger message. If None is given (default) the apply operation is considered safe

setEventBufferPeriod(period)[source]

Set the period at wich fireBufferedEvents() will be called. If period is 0, the event buffering is disabled (i.e., events are fired as soon as they are received)

Parameters

period (float) – period in seconds for the automatic event firing. period=0 will disable the event buffering.

setEventFilters(filters=None, preqt=False)[source]

sets the taurus event filters list. The filters are run in order, using each output to feed the next filter. A filter must be a function that accepts 3 arguments (evt_src, evt_type, evt_value) If the event is to be ignored, the filter must return None. If the event is not to be ignored, filter must return a (evt_src, evt_type, evt_value) tuple which may (or not) differ from the input.

For a library of common filters, see taurus/core/util/eventfilters.py

Parameters
  • filters (sequence) – a sequence of filters

  • preqt (bool) – If true, set the pre-filters (that are applied in eventReceived, at the python thread), otherwise, set the filters to be applied at the main Qt thread (default)

Note: If you are setting a filter that applies a transformation on the parameters, you may want to generate a fake event to force the last value to be filtered as well. This can be done as in this example:

TaurusBaseComponent.fireEvent( TaurusBaseComponent.getModelObj(),
    taurus.core.taurusbasetypes.TaurusEventType.Periodic,
    TaurusBaseComponent.getModelObj().getValueObj())

See also: insertEventFilter

setForceDangerousOperations(yesno)[source]

Forces/clears the dangerous operations

Parameters

yesno (bool) – force or not the dangerous operations

setFormat(format)[source]

Method to set the FORMAT attribute for this instance. It also resets the internal format string, which will be recalculated in the next call to displayValue()

Parameters

format (str or callable) – A format string or a formatter callable (or the callable name in “full.module.callable” format)

setModel(model, *, key=<class 'taurus.qt.qtgui.base.taurusbase._DEFAULT'>)[source]

Sets/unsets the model name for the given key. If key is MLIST, a model is set for each name in the model sequence, new model keys are automatically added to the object’s modelList attribute and the corresponding models are attached using those keys. The new keys are of the form (MLIST, i) where i is the index of the corresponding model name in the model sequence.

Parameters
  • model (str (or sequence of str if key is MLIST)) – the new model name. If key is MLIST, model is expected to be a sequence of model names.

  • key (object) – the model key. Defaults to first element of .modelKeys

setModelCheck(**kwargs)

Deprecated since version 5.1.0: Use setModel instead

setModelInConfig(yesno)[source]

Sets whether the model-related properties should be stored for this widget when creating the config dict with createConfig() (and restored when calling applyConfig()). By default this is not enabled. The following properties are affected by this:

  • “model”

Parameters

yesno (bool) – If True, the model-related properties will be registered as config properties. If False, they will be unregistered.

See also

registerConfigProperty(), createConfig(), applyConfig()

setModelName(**kwargs)

Deprecated since version 5.1.0.

setModifiableByUser(modifiable)[source]

sets whether the user is allowed to modify the look&feel

Parameters

modifiable (bool) – True allows the user to modify certain properties of the widget. False restricts those modifications

setNoneValue(v)[source]

Sets the new string representation when no model or no model value exists.

Parameters

v (str) – the string representation for an invalid value

setPaused(paused=True)[source]

Toggles the pause mode.

Parameters

paused (bool) – whether or not to pause (default = True)

setShowQuality(showQuality)[source]

Sets/unsets the show quality property

Parameters

showQuality (bool) – whether or not to show the quality

setShowText(showText)[source]

Sets/unsets showing the display value of the model

Parameters

showText (bool) – whether or not to show the display value

setTaurusPopupMenu(**kwargs)

Sets/unsets the taurus popup menu

param menuData

an xml representing the popup menu

type menuData

str

Deprecated since version 4.5.3a.

setUseParentModel(**kwargs)

Deprecated since version 4.3.2: Use explicit models including the parent model instead

property taurusEvent

Base signal taurusEvent

toolTipObjToStr(toolTipObj)[source]

Converts a python dict to a tooltip string.

Parameters

toolTipObj (dict) – a python object

Returns

a tooltip

Return type

str

updateStyle()[source]

Method called when the component detects an event that triggers a change in the style. Default implementation doesn’t do anything. Overwrite when necessary