Merge pull request #106 from Carifio24/fix-image-qt-export-crash

Fix technical issues with Qt image exporter

glue_plotly/common/image.py

@@ -49,6 +49,14 @@ def layout_config(viewer):
                               showlegend=True)
 
 
+def get_mpl_renderer(figure):
+    if hasattr(figure.canvas, "get_renderer"):
+        return figure.canvas.get_renderer()
+    elif hasattr(figure, "_get_renderer"):
+        return figure._get_renderer()
+    return None
+
+
 def axes_data_from_mpl(viewer):
     axes_data = {}
 
@@ -58,10 +66,17 @@ def axes_data_from_mpl(viewer):
 
     for helper in axes.coords:
         ticks = helper.ticks
-        ticklabels = helper.ticklabels
+        if hasattr(helper, '_ticklabels'):
+            # We need to use the private attribute due to a bug in astropy 7
+            # See https://github.com/astropy/astropy/pull/17444
+            ticklabels = helper._ticklabels
+        else:
+            ticklabels = helper.ticklabels
         for axis in ticklabels.get_visible_axes():
             ax = 'x' if axis in ['t', 'b'] else 'y'
             ax_idx = 0 if ax == 'x' else 1
+            if not hasattr(ticks, "ticks_locs"):
+                ticks.draw(get_mpl_renderer(viewer.figure))
             locations = sorted([loc[0][ax_idx] for loc in ticks.ticks_locs[axis]])
             labels = ticklabels.text[axis]
             if ax == 'y':

glue_plotly/html_exporters/qt/image.py

@@ -32,19 +32,13 @@ class PlotlyImage2DExport(Tool):
     tool_tip = 'Save Plotly HTML page'
 
     @messagebox_on_error(PLOTLY_ERROR_MESSAGE)
-    def _export_to_plotly(self, filename, checked_dictionary):
+    def _export_to_plotly(self, filename, checked_dictionary, config):
 
         layers = layers_to_export(self.viewer)
         add_data_label = data_count(layers) > 1
 
-        config = layout_config(self.viewer)
-
-        # TODO: Need to determine how to makes axes from bqplot
-        ax = axes_data_from_mpl(self.viewer)
-        config.update(**ax)
-        secondary_x = 'xaxis2' in ax
-        secondary_y = 'yaxis2' in ax
-        config["showlegend"] = len(layers) > 1
+        secondary_x = 'xaxis2' in config
+        secondary_y = 'yaxis2' in config
 
         if secondary_x or secondary_y:
             fig = make_subplots(specs=[[{"secondary_y": True}]], horizontal_spacing=0, vertical_spacing=0)
@@ -87,7 +81,15 @@ def activate(self):
         if not filename:
             return
 
-        worker = Worker(self._export_to_plotly, filename, checked_dictionary)
+        # It would be better to create the layout config in `_export_to_plotly`.
+        # But we get some of our axis font sizes from matplotlib, some of which seems to cause problems
+        # when run in a QThread. So for now, we get the layout config here.
+        config = layout_config(self.viewer)
+        ax = axes_data_from_mpl(self.viewer)
+        config.update(**ax)
+        config["showlegend"] = len(layers) > 1
+
+        worker = Worker(self._export_to_plotly, filename, checked_dictionary, config)
         exp_dialog = export_dialog.ExportDialog(parent=self.viewer)
         worker.result.connect(exp_dialog.close)
         worker.error.connect(exp_dialog.close)