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Source code for matplotlib.backend_managers

    Class that makes the bridge between user interaction (key press,
    toolbar clicks, ..) and the actions in response to the user inputs.

import warnings

import matplotlib.cbook as cbook
import matplotlib.widgets as widgets
from matplotlib.rcsetup import validate_stringlist
import matplotlib.backend_tools as tools

[docs]class ToolEvent(object): """Event for tool manipulation (add/remove)""" def __init__(self, name, sender, tool, data=None): = name self.sender = sender self.tool = tool = data
[docs]class ToolTriggerEvent(ToolEvent): """Event to inform that a tool has been triggered""" def __init__(self, name, sender, tool, canvasevent=None, data=None): ToolEvent.__init__(self, name, sender, tool, data) self.canvasevent = canvasevent
[docs]class ToolManagerMessageEvent(object): """ Event carrying messages from toolmanager Messages usually get displayed to the user by the toolbar """ def __init__(self, name, sender, message): = name self.sender = sender self.message = message
[docs]class ToolManager(object): """ Helper class that groups all the user interactions for a Figure. Attributes ---------- figure: `Figure` keypresslock: `widgets.LockDraw` `LockDraw` object to know if the `canvas` key_press_event is locked messagelock: `widgets.LockDraw` `LockDraw` object to know if the message is available to write """ def __init__(self, figure=None): warnings.warn('Treat the new Tool classes introduced in v1.5 as ' + 'experimental for now, the API will likely change in ' + 'version 2.1 and perhaps the rcParam as well') self._key_press_handler_id = None self._tools = {} self._keys = {} self._toggled = {} self._callbacks = cbook.CallbackRegistry() # to process keypress event self.keypresslock = widgets.LockDraw() self.messagelock = widgets.LockDraw() self._figure = None self.set_figure(figure) @property def canvas(self): """Canvas managed by FigureManager""" if not self._figure: return None return self._figure.canvas @property def figure(self): """Figure that holds the canvas""" return self._figure @figure.setter def figure(self, figure): self.set_figure(figure)
[docs] def set_figure(self, figure, update_tools=True): """ Bind the given figure to the tools. Parameters ---------- figure : `.Figure` update_tools : bool Force tools to update figure """ if self._key_press_handler_id: self.canvas.mpl_disconnect(self._key_press_handler_id) self._figure = figure if figure: self._key_press_handler_id = self.canvas.mpl_connect( 'key_press_event', self._key_press) if update_tools: for tool in self._tools.values(): tool.figure = figure
[docs] def toolmanager_connect(self, s, func): """ Connect event with string *s* to *func*. Parameters ---------- s : String Name of the event The following events are recognized - 'tool_message_event' - 'tool_removed_event' - 'tool_added_event' For every tool added a new event is created - 'tool_trigger_TOOLNAME` Where TOOLNAME is the id of the tool. func : function Function to be called with signature def func(event) """ return self._callbacks.connect(s, func)
[docs] def toolmanager_disconnect(self, cid): """ Disconnect callback id *cid* Example usage:: cid = toolmanager.toolmanager_connect('tool_trigger_zoom', on_press) #...later toolmanager.toolmanager_disconnect(cid) """ return self._callbacks.disconnect(cid)
[docs] def message_event(self, message, sender=None): """ Emit a `ToolManagerMessageEvent`""" if sender is None: sender = self s = 'tool_message_event' event = ToolManagerMessageEvent(s, sender, message) self._callbacks.process(s, event)
@property def active_toggle(self): """Currently toggled tools""" return self._toggled
[docs] def get_tool_keymap(self, name): """ Get the keymap associated with the specified tool Parameters ---------- name : string Name of the Tool Returns ------- list : list of keys associated with the Tool """ keys = [k for k, i in self._keys.items() if i == name] return keys
def _remove_keys(self, name): for k in self.get_tool_keymap(name): del self._keys[k]
[docs] def update_keymap(self, name, *keys): """ Set the keymap to associate with the specified tool Parameters ---------- name : string Name of the Tool keys : keys to associate with the Tool """ if name not in self._tools: raise KeyError('%s not in Tools' % name) self._remove_keys(name) for key in keys: for k in validate_stringlist(key): if k in self._keys: warnings.warn('Key %s changed from %s to %s' % (k, self._keys[k], name)) self._keys[k] = name
[docs] def remove_tool(self, name): """ Remove tool from `ToolManager` Parameters ---------- name : string Name of the Tool """ tool = self.get_tool(name) tool.destroy() # If is a toggle tool and toggled, untoggle if getattr(tool, 'toggled', False): self.trigger_tool(tool, 'toolmanager') self._remove_keys(name) s = 'tool_removed_event' event = ToolEvent(s, self, tool) self._callbacks.process(s, event) del self._tools[name]
[docs] def add_tool(self, name, tool, *args, **kwargs): """ Add *tool* to `ToolManager` If successful adds a new event `tool_trigger_name` where **name** is the **name** of the tool, this event is fired everytime the tool is triggered. Parameters ---------- name : str Name of the tool, treated as the ID, has to be unique tool : class_like, i.e. str or type Reference to find the class of the Tool to added. Notes ----- args and kwargs get passed directly to the tools constructor. See Also -------- matplotlib.backend_tools.ToolBase : The base class for tools. """ tool_cls = self._get_cls_to_instantiate(tool) if not tool_cls: raise ValueError('Impossible to find class for %s' % str(tool)) if name in self._tools: warnings.warn('A "Tool class" with the same name already exists, ' 'not added') return self._tools[name] tool_obj = tool_cls(self, name, *args, **kwargs) self._tools[name] = tool_obj if tool_cls.default_keymap is not None: self.update_keymap(name, tool_cls.default_keymap) # For toggle tools init the radio_group in self._toggled if isinstance(tool_obj, tools.ToolToggleBase): # None group is not mutually exclusive, a set is used to keep track # of all toggled tools in this group if tool_obj.radio_group is None: self._toggled.setdefault(None, set()) else: self._toggled.setdefault(tool_obj.radio_group, None) # If initially toggled if tool_obj.toggled: self._handle_toggle(tool_obj, None, None, None) tool_obj.set_figure(self.figure) self._tool_added_event(tool_obj) return tool_obj
def _tool_added_event(self, tool): s = 'tool_added_event' event = ToolEvent(s, self, tool) self._callbacks.process(s, event) def _handle_toggle(self, tool, sender, canvasevent, data): """ Toggle tools, need to untoggle prior to using other Toggle tool Called from trigger_tool Parameters ---------- tool: Tool object sender: object Object that wishes to trigger the tool canvasevent : Event Original Canvas event or None data : Object Extra data to pass to the tool when triggering """ radio_group = tool.radio_group # radio_group None is not mutually exclusive # just keep track of toggled tools in this group if radio_group is None: if in self._toggled[None]: self._toggled[None].remove( else: self._toggled[None].add( return # If the tool already has a toggled state, untoggle it if self._toggled[radio_group] == toggled = None # If no tool was toggled in the radio_group # toggle it elif self._toggled[radio_group] is None: toggled = # Other tool in the radio_group is toggled else: # Untoggle previously toggled tool self.trigger_tool(self._toggled[radio_group], self, canvasevent, data) toggled = # Keep track of the toggled tool in the radio_group self._toggled[radio_group] = toggled def _get_cls_to_instantiate(self, callback_class): # Find the class that corresponds to the tool if isinstance(callback_class, str): # FIXME: make more complete searching structure if callback_class in globals(): callback_class = globals()[callback_class] else: mod = 'backend_tools' current_module = __import__(mod, globals(), locals(), [mod], 1) callback_class = getattr(current_module, callback_class, False) if callable(callback_class): return callback_class else: return None
[docs] def trigger_tool(self, name, sender=None, canvasevent=None, data=None): """ Trigger a tool and emit the tool_trigger_[name] event Parameters ---------- name : string Name of the tool sender: object Object that wishes to trigger the tool canvasevent : Event Original Canvas event or None data : Object Extra data to pass to the tool when triggering """ tool = self.get_tool(name) if tool is None: return if sender is None: sender = self self._trigger_tool(name, sender, canvasevent, data) s = 'tool_trigger_%s' % name event = ToolTriggerEvent(s, sender, tool, canvasevent, data) self._callbacks.process(s, event)
def _trigger_tool(self, name, sender=None, canvasevent=None, data=None): """ Trigger on a tool Method to actually trigger the tool """ tool = self.get_tool(name) if isinstance(tool, tools.ToolToggleBase): self._handle_toggle(tool, sender, canvasevent, data) # Important!!! # This is where the Tool object gets triggered tool.trigger(sender, canvasevent, data) def _key_press(self, event): if event.key is None or self.keypresslock.locked(): return name = self._keys.get(event.key, None) if name is None: return self.trigger_tool(name, canvasevent=event) @property def tools(self): """Return the tools controlled by `ToolManager`""" return self._tools
[docs] def get_tool(self, name, warn=True): """ Return the tool object, also accepts the actual tool for convenience Parameters ---------- name : str, ToolBase Name of the tool, or the tool itself warn : bool, optional If this method should give warnings. """ if isinstance(name, tools.ToolBase) and in self._tools: return name if name not in self._tools: if warn: warnings.warn("ToolManager does not control tool %s" % name) return None return self._tools[name]