Change ImageViewer to automatically call plugins.

skimage/viewer/viewers/core.py

@@ -104,6 +104,8 @@ class ImageViewer(QtGui.QMainWindow):
         self.close()
 
     def show(self):
+        for p in self.plugins:
+            p.show()
         super(ImageViewer, self).show()
         sys.exit(qApp.exec_())
 

viewer_examples/plugins/canny.py

@@ -5,6 +5,5 @@ from skimage.viewer.plugins.canny import CannyPlugin
 
 image = data.camera()
 viewer = ImageViewer(image)
-p = CannyPlugin(viewer)
-p.show()
+CannyPlugin(viewer)
 viewer.show()

viewer_examples/plugins/lineprofile.py

@@ -5,6 +5,5 @@ from skimage.viewer.plugins.lineprofile import LineProfile
 
 image = data.camera()
 viewer = ImageViewer(image)
-p = LineProfile(viewer)
-p.show()
+LineProfile(viewer)
 viewer.show()