Fix #2472: Draw the spines on top of twin axes

matplotlib · mdboom · Oct 14, 2013 · Oct 1, 2013 · Oct 1, 2013 · 6103f64fede1d8a393af6384d8404704e1eaafbb
commit 6103f64fede1d8a393af6384d8404704e1eaafbb
diff --git a/lib/matplotlib/axes.py b/lib/matplotlib/axes.py
@@ -8036,13 +8036,13 @@ def twinx(self):
            For those who are 'picking' artists while using twinx, pick
            events are only called for the artists in the top-most axes.
        """
-
-        ax2 = self._make_twin_axes(sharex=self, frameon=False)
+        ax2 = self._make_twin_axes(sharex=self)
        ax2.yaxis.tick_right()
        ax2.yaxis.set_label_position('right')
        ax2.yaxis.set_offset_position('right')
        self.yaxis.tick_left()
        ax2.xaxis.set_visible(False)
+        ax2.patch.set_visible(False)
        return ax2

    def twiny(self):
@@ -8061,11 +8061,12 @@ def twiny(self):
            events are only called for the artists in the top-most axes.
        """

-        ax2 = self._make_twin_axes(sharey=self, frameon=False)
+        ax2 = self._make_twin_axes(sharey=self)
        ax2.xaxis.tick_top()
        ax2.xaxis.set_label_position('top')
        self.xaxis.tick_bottom()
        ax2.yaxis.set_visible(False)
+        ax2.patch.set_visible(False)
        return ax2

    def get_shared_x_axes(self):

diff --git a/lib/matplotlib/tests/baseline_images/test_axes/twin_spines_on_top.png b/lib/matplotlib/tests/baseline_images/test_axes/twin_spines_on_top.png
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -1646,6 +1646,27 @@ def make_patch_spines_invisible(ax):
    host.tick_params(axis='x', **tkw)


+@image_comparison(baseline_images=['twin_spines_on_top'], extensions=['png'],
+                  remove_text=True)
+def test_twin_spines_on_top():
+    matplotlib.rcParams['axes.linewidth'] = 48.0
+    matplotlib.rcParams['lines.linewidth'] = 48.0
+
+    fig = plt.figure()
+    ax1 = fig.add_subplot(1, 1, 1)
+
+    data = np.array([[1000, 1100, 1200, 1250],
+                     [310, 301, 360, 400]])
+
+    ax2 = ax1.twinx()
+
+    ax1.plot(data[0], data[1]/1E3, color='#BEAED4')
+    ax1.fill_between(data[0], data[1]/1E3, color='#BEAED4', alpha=.8)
+
+    ax2.plot(data[0], data[1]/1E3, color='#7FC97F')
+    ax2.fill_between(data[0], data[1]/1E3, color='#7FC97F', alpha=.5)
+
+
 @cleanup
 def test_vline_limit():
    fig = plt.figure()