10% work

complete most xml relax ng work.
work on real interface xml
work on python scripts for parsing interface xml

python/mine/ri_seq.py

@@ -0,0 +1,44 @@
+#!/usr/bin/python
+
+current_sequence=""
+previous_sequences=[]
+dict={}
+
+class Sequence:
+    ''' implement sequence in interface xml'''
+    def __init__(self, xml_node):
+        self.steps = [ s.attributes["name"].value for s in xml_node.childNodes
+                 if s.nodeType == s.ELEMENT_NODE and s.nodeName == "widget" ]
+        self.current_step = 0
+
+def construct(xml_root):
+    ''' construct Sequence's static members'''
+    global current_sequence
+    current_sequence = xml_root.attributes["sequence"].value
+    for s in xml_root.childNodes:
+        if s.nodeType == s.ELEMENT_NODE and s.nodeName == "sequence":
+            dict[s.attributes["name"].value] = Sequence(s)
+
+def previous():
+    global current_sequence
+    cur_seq = dict[current_sequence]
+    if cur_seq.current_step:
+        cur_seq.current_step -= 1
+        return cur_seq.steps[cur_seq.current_step]
+    # current sequence already in first step
+    elif previous_sequences:
+        current_sequence = previous_sequences.pop()
+        cur_seq = dict[current_sequence]
+        return cur_seq.steps[cur_seq.current_step]
+
+def next():
+    global current_sequence
+    cur_seq = dict[current_sequence]
+    if cur_seq.current_step < len(cur_seq.steps)-1:
+        cur_seq.current_step += 1
+        return cur_seq.steps[cur_seq.current_step]
+    # current sequence already in last step
+    elif previous_sequences:
+        current_sequence = previous_sequences.pop()
+        cur_seq = dict[current_sequence]
+        return cur_seq.steps[cur_seq.current_step]