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1"""
2Manage figures for the pyplot interface.
3"""
5import atexit
6from collections import OrderedDict
9class Gcf:
10 """
11 Singleton to maintain the relation between figures and their managers, and
12 keep track of and "active" figure and manager.
14 The canvas of a figure created through pyplot is associated with a figure
15 manager, which handles the interaction between the figure and the backend.
16 pyplot keeps track of figure managers using an identifier, the "figure
17 number" or "manager number" (which can actually be any hashable value);
18 this number is available as the :attr:`number` attribute of the manager.
20 This class is never instantiated; it consists of an `OrderedDict` mapping
21 figure/manager numbers to managers, and a set of class methods that
22 manipulate this `OrderedDict`.
24 Attributes
25 ----------
26 figs : OrderedDict
27 `OrderedDict` mapping numbers to managers; the active manager is at the
28 end.
29 """
31 figs = OrderedDict()
33 @classmethod
34 def get_fig_manager(cls, num):
35 """
36 If manager number *num* exists, make it the active one and return it;
37 otherwise return *None*.
38 """
39 manager = cls.figs.get(num, None)
40 if manager is not None:
41 cls.set_active(manager)
42 return manager
44 @classmethod
45 def destroy(cls, num):
46 """
47 Destroy manager *num* -- either a manager instance or a manager number.
49 In the interactive backends, this is bound to the window "destroy" and
50 "delete" events.
52 It is recommended to pass a manager instance, to avoid confusion when
53 two managers share the same number.
54 """
55 if all(hasattr(num, attr) for attr in ["num", "destroy"]):
56 manager = num
57 if cls.figs.get(manager.num) is manager:
58 cls.figs.pop(manager.num)
59 else:
60 try:
61 manager = cls.figs.pop(num)
62 except KeyError:
63 return
64 if hasattr(manager, "_cidgcf"):
65 manager.canvas.mpl_disconnect(manager._cidgcf)
66 manager.destroy()
68 @classmethod
69 def destroy_fig(cls, fig):
70 """Destroy figure *fig*."""
71 num = next((manager.num for manager in cls.figs.values()
72 if manager.canvas.figure == fig), None)
73 if num is not None:
74 cls.destroy(num)
76 @classmethod
77 def destroy_all(cls):
78 """Destroy all figures."""
79 for manager in list(cls.figs.values()):
80 manager.canvas.mpl_disconnect(manager._cidgcf)
81 manager.destroy()
82 cls.figs.clear()
84 @classmethod
85 def has_fignum(cls, num):
86 """Return whether figure number *num* exists."""
87 return num in cls.figs
89 @classmethod
90 def get_all_fig_managers(cls):
91 """Return a list of figure managers."""
92 return list(cls.figs.values())
94 @classmethod
95 def get_num_fig_managers(cls):
96 """Return the number of figures being managed."""
97 return len(cls.figs)
99 @classmethod
100 def get_active(cls):
101 """Return the active manager, or *None* if there is no manager."""
102 return next(reversed(cls.figs.values())) if cls.figs else None
104 @classmethod
105 def _set_new_active_manager(cls, manager):
106 """Adopt *manager* into pyplot and make it the active manager."""
107 if not hasattr(manager, "_cidgcf"):
108 manager._cidgcf = manager.canvas.mpl_connect(
109 "button_press_event", lambda event: cls.set_active(manager))
110 fig = manager.canvas.figure
111 fig.number = manager.num
112 label = fig.get_label()
113 if label:
114 manager.set_window_title(label)
115 cls.set_active(manager)
117 @classmethod
118 def set_active(cls, manager):
119 """Make *manager* the active manager."""
120 cls.figs[manager.num] = manager
121 cls.figs.move_to_end(manager.num)
123 @classmethod
124 def draw_all(cls, force=False):
125 """
126 Redraw all stale managed figures, or, if *force* is True, all managed
127 figures.
128 """
129 for manager in cls.get_all_fig_managers():
130 if force or manager.canvas.figure.stale:
131 manager.canvas.draw_idle()
134atexit.register(Gcf.destroy_all)