Dec 21, 2018 · May 29, 2022 · May 29, 2022
diff --git a/examples/text_labels_and_annotations/legend.py b/examples/text_labels_and_annotations/legend.py
 ax.plot(a, d, 'k:', label='Data length')
 ax.plot(a, c + d, 'k', label='Total message length')

 #Create an arrow with pre-defined label.
 #Create an arrow with pre-defined label.
 ax.annotate("", xy=(1.5, 4.5), xytext=(1.5, 9.0),
            arrowprops={'arrowstyle':'<->', 'color':'C7'}, label='Distance')
            arrowprops={'arrowstyle':'<->', 'color':'C7'}, label='Distance')

 legend = ax.legend(loc='upper center', shadow=True, fontsize='large')

diff --git a/lib/matplotlib/legend_handler.py b/lib/matplotlib/legend_handler.py
    """
    Handler for `~.FancyArrowPatch` instances.
    """
    def _create_patch(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize):
    def _create_patch(self, legend, orig_handle, xdescent, ydescent, width,
                      height, fontsize):
        arrow = FancyArrowPatch([-xdescent,
                                 -ydescent + height / 2],
                                [-xdescent + width,
    """
    Handler for `.Annotation` instances.
    Defers to `HandlerFancyArrowPatch` to draw the annotation arrow (if any).

    Parameters
    ----------
    pad : float, optional
        If None, fall back to :rc:`legend.borderpad` as the default.
        In units of fraction of font size. Default is None
        .
    width_ratios : two-tuple, optional
        The relative width of the respective text/arrow legend annotation pair.
        Default is (1, 4).
    """

    def __init__(self, pad=None, width_ratios=(1, 4), **kwargs):

        self._pad = pad
        self._width_ratios = width_ratios

        HandlerBase.__init__(self, **kwargs)

    def create_artists(self, legend, orig_handle, xdescent, ydescent, width,
                       height, fontsize, trans):

        if orig_handle.arrow_patch is not None:

            # Arrow without text

            handler = HandlerFancyArrowPatch()
            handle = orig_handle.arrow_patch
        else:
            # No arrow
            handler = HandlerPatch()
            # Dummy patch to copy properties from to rectangle patch
            handle = Rectangle(width=0, height=0, xy=(0, 0), color='none')

        return handler.create_artists(legend, handle, xdescent, ydescent,
                                      width, height, fontsize, trans)
diff --git a/lib/matplotlib/tests/test_legend.py b/lib/matplotlib/tests/test_legend.py

    assert markers == new_markers == _markers
    assert labels == new_labels


 def test_annotation_legend():
    fig, ax = plt.subplots()
    # Add annotation with arrow and label
    ax.annotate("", xy=(0.5, 0.5), xytext=(0.5, 0.7),
                arrowprops={'arrowstyle': '<->'}, label="Bar")
    legend = ax.legend()
    assert len(legend.get_texts()) == 1
    # No arrow, no label
    ax.annotate("Foo", xy=(0.3, 0.3))
    legend = ax.legend()
    assert len(legend.get_texts()) == 1
    # Arrow, no label
    ax.annotate("FooBar", xy=(0.7, 0.7), xytext=(0.7, 0.9),
                arrowprops={'arrowstyle': '->'})
    legend = ax.legend()
    assert len(legend.get_texts()) == 1
    # Add another annotation with arrow and label. now with non-empty text
    ax.annotate("Foo", xy=(0.1, 0.1), xytext=(0.1, 0.7),
                arrowprops={'arrowstyle': '<-'}, label="Foo")
    legend = ax.legend()
    assert len(legend.get_texts()) == 2
    # Add annotation without arrow, but with label
    ax.annotate("Foo", xy=(0.2, 0.2), xytext=(0.2, 0.6), label="Foo")
    legend = ax.legend()
    assert len(legend.get_texts()) == 3
Original file line number	Diff line number	Diff line change
Expand Up		@@ -21,9 +21,9 @@
		ax.plot(a, d, 'k:', label='Data length')
		ax.plot(a, c + d, 'k', label='Total message length')

		#Create an arrow with pre-defined label.
		#Create an arrow with pre-defined label.
		ax.annotate("", xy=(1.5, 4.5), xytext=(1.5, 9.0),
		arrowprops={'arrowstyle':'<->', 'color':'C7'}, label='Distance')
		arrowprops={'arrowstyle':'<->', 'color':'C7'}, label='Distance')

		legend = ax.legend(loc='upper center', shadow=True, fontsize='large')

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -812,7 +812,8 @@ class HandlerFancyArrowPatch(HandlerPatch):
		"""
		Handler for `~.FancyArrowPatch` instances.
		"""
		def _create_patch(self, legend, orig_handle, xdescent, ydescent, width, height, fontsize):
		def _create_patch(self, legend, orig_handle, xdescent, ydescent, width,
		height, fontsize):
		arrow = FancyArrowPatch([-xdescent,
		-ydescent + height / 2],
		[-xdescent + width,
Expand All		@@ -826,34 +827,19 @@ class HandlerAnnotation(HandlerBase):
		"""
		Handler for `.Annotation` instances.
		Defers to `HandlerFancyArrowPatch` to draw the annotation arrow (if any).

		Parameters
		----------
		pad : float, optional
		If None, fall back to :rc:`legend.borderpad` as the default.
		In units of fraction of font size. Default is None
		.
		width_ratios : two-tuple, optional
		The relative width of the respective text/arrow legend annotation pair.
		Default is (1, 4).
		"""

		def __init__(self, pad=None, width_ratios=(1, 4), **kwargs):

		self._pad = pad
		self._width_ratios = width_ratios

		HandlerBase.__init__(self, **kwargs)

		def create_artists(self, legend, orig_handle, xdescent, ydescent, width,
		height, fontsize, trans):

		if orig_handle.arrow_patch is not None:

		# Arrow without text

		handler = HandlerFancyArrowPatch()
		handle = orig_handle.arrow_patch
		else:
		# No arrow
		handler = HandlerPatch()
		# Dummy patch to copy properties from to rectangle patch
		handle = Rectangle(width=0, height=0, xy=(0, 0), color='none')

		return handler.create_artists(legend, handle, xdescent, ydescent,
		width, height, fontsize, trans)
Original file line number	Diff line number	Diff line change
Expand Up		@@ -927,3 +927,30 @@ def test_legend_markers_from_line2d():

		assert markers == new_markers == _markers
		assert labels == new_labels


		def test_annotation_legend():
		fig, ax = plt.subplots()
		# Add annotation with arrow and label
		ax.annotate("", xy=(0.5, 0.5), xytext=(0.5, 0.7),
		arrowprops={'arrowstyle': '<->'}, label="Bar")
		legend = ax.legend()
		assert len(legend.get_texts()) == 1
		# No arrow, no label
		ax.annotate("Foo", xy=(0.3, 0.3))
		legend = ax.legend()
		assert len(legend.get_texts()) == 1
		# Arrow, no label
		ax.annotate("FooBar", xy=(0.7, 0.7), xytext=(0.7, 0.9),
		arrowprops={'arrowstyle': '->'})
		legend = ax.legend()
		assert len(legend.get_texts()) == 1
		# Add another annotation with arrow and label. now with non-empty text
		ax.annotate("Foo", xy=(0.1, 0.1), xytext=(0.1, 0.7),
		arrowprops={'arrowstyle': '<-'}, label="Foo")
		legend = ax.legend()
		assert len(legend.get_texts()) == 2
		# Add annotation without arrow, but with label
		ax.annotate("Foo", xy=(0.2, 0.2), xytext=(0.2, 0.6), label="Foo")
		legend = ax.legend()
		assert len(legend.get_texts()) == 3