Source Code for Module rqt_joint_trajectory_controller.update_combo

 1  #!/usr/bin/env python 
 2   
 3  # Copyright (C) 2014, PAL Robotics S.L. 
 4  # 
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27   
28 -def update_combo(combo, new_vals): 
29      """ 
30      Update the contents of a combo box with a set of new values. 
31   
32      If the previously selected element is still present in the new values, it 
33      will remain as active selection, even if its index has changed. This will 
34      not trigger any signal. 
35   
36      If the previously selected element is no longer present in the new values, 
37      the combo will unset its selection. This will trigger signals for changed 
38      element. 
39      """ 
40      selected_val = combo.currentText() 
41      old_vals = [combo.itemText(i) for i in range(combo.count())] 
42   
43      # Check if combo items changed 
44      if not _is_permutation(old_vals, new_vals): 
45          # Determine if selected value is in the new list 
46          selected_id = -1 
47          try: 
48              selected_id = new_vals.index(selected_val) 
49          except (ValueError): 
50              combo.setCurrentIndex(-1) 
51   
52          # Re-populate items 
53          combo.blockSignals(True)  # No need to notify these changes 
54          combo.clear() 
55          combo.insertItems(0, new_vals) 
56          combo.setCurrentIndex(selected_id)  # Restore selection 
57          combo.blockSignals(False) 
58   
59 -def _is_permutation(a, b): 
60      """ 
61      @type a [] 
62      @type b [] 
63      @return True if C{a} is a permutation of C{b}, false otherwise 
64      @rtype bool 
65      """ 
66      return len(a) == len(b) and sorted(a) == sorted(b) 
67