initialize zoom center even when viewer not shown (#3222)

* initialize zoom center even when viewer not shown

* simplified regression test

jdaviz/configs/cubeviz/plugins/viewers.py

@@ -31,7 +31,7 @@ class CubevizImageView(JdavizViewerMixin, WithSliceSelection, BqplotImageView):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         # provide reference from state back to viewer to use for zoom syncing
-        self.state._viewer = self
+        self.state._set_viewer(self)
 
         self._subscribe_to_layers_update()
         self.state.add_callback('reference_data', self._initial_x_axis)

jdaviz/configs/imviz/plugins/viewers.py

@@ -36,7 +36,7 @@ class ImvizImageView(JdavizViewerMixin, BqplotImageView, AstrowidgetsImageViewer
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         # provide reference from state back to viewer to use for zoom syncing
-        self.state._viewer = self
+        self.state._set_viewer(self)
         self.init_astrowidgets_api()
         self._subscribe_to_layers_update()
 

jdaviz/configs/imviz/tests/test_viewers.py

@@ -97,6 +97,15 @@ def test_mastviz_config():
     assert im.app.data_collection[0].shape == (2, 2)
 
 
+def test_zoom_center_radius_init(imviz_helper):
+    """Regression test for https://github.com/spacetelescope/jdaviz/issues/3217"""
+    arr = np.ones((10, 10))
+    imviz_helper.load_data(arr, data_label='my_array')
+    assert imviz_helper.default_viewer._obj.state.zoom_center_x > 0
+    assert imviz_helper.default_viewer._obj.state.zoom_center_y > 0
+    assert imviz_helper.default_viewer._obj.state.zoom_radius > 0
+
+
 class TestDeleteData(BaseImviz_WCS_NoWCS):
 
     def test_plot_options_after_destroy(self):

jdaviz/configs/rampviz/plugins/viewers.py

@@ -106,7 +106,7 @@ class RampvizImageView(JdavizViewerMixin, WithSliceSelection, BqplotImageView):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         # provide reference from state back to viewer to use for zoom syncing
-        self.state._viewer = self
+        self.state._set_viewer(self)
 
         self._subscribe_to_layers_update()
         self.state.add_callback('reference_data', self._initial_x_axis)

jdaviz/core/freezable_state.py

@@ -71,6 +71,10 @@ def __init__(self, *args, **kwargs):
             self.add_callback(attr, self._set_axes_lim)
         super().__init__(*args, **kwargs)
 
+    def _set_viewer(self, viewer):
+        self._viewer = viewer
+        self._set_axes_lim()
+
     @contextmanager
     def during_zoom_sync(self):
         self._during_zoom_sync = True
@@ -82,7 +86,7 @@ def during_zoom_sync(self):
         self._during_zoom_sync = False
 
     def _set_zoom_radius_center(self, *args):
-        if self._during_zoom_sync or not hasattr(self, '_viewer') or self._viewer.shape is None:
+        if self._during_zoom_sync or not hasattr(self, '_viewer'):
             return
 
         # When WCS-linked (displayed on the sky): zoom_center_x/y and zoom_radius are in sky units,
@@ -117,7 +121,7 @@ def _set_axes_aspect_ratio(self, axes_ratio):
         self._set_axes_lim()
 
     def _set_axes_lim(self, *args):
-        if self._during_zoom_sync or not hasattr(self, '_viewer') or self._viewer.shape is None:
+        if self._during_zoom_sync or not hasattr(self, '_viewer'):
             return
         if None in (self.x_min, self.x_max, self.y_min, self.y_max):
             return