[Android] Auto-generate API 14 resources from the existing API 17 resources.

build/android/gyp/mirror_resources.py

Index: build/android/gyp/mirror_resources.py
diff --git a/build/android/gyp/mirror_resources.py b/build/android/gyp/mirror_resources.py
new file mode 100755
index 0000000000000000000000000000000000000000..b06f746bdf9fbfd7e3dc48dd0bc9986a86d99ae2
--- /dev/null
+++ b/build/android/gyp/mirror_resources.py
@@ -0,0 +1,139 @@
+#!/usr/bin/env python
+#
+# Copyright 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import optparse
+import os
+import re
+import sys
+import xml.etree.cElementTree as ET
+
+from util import build_utils
+
+
+ATTRIBUTE_PREFIX = '{http://schemas.android.com/apk/res/android}'
+
+ATTRIBUTES_TO_MIRROR = ['paddingLeft',
+                        'drawableLeft',
+                        'layout_alignLeft',
+                        'layout_marginLeft',
+                        'layout_alignParentLeft',
+                        'layout_toLeftOf',
+                        'paddingRight',
+                        'drawableRight',
+                        'layout_alignRight',
+                        'layout_marginRight',
+                        'layout_alignParentRight',
+                        'layout_toRightOf',
+                        'gravity',
+                        'layout_gravity']
+
+ATTRIBUTES_TO_MIRROR = set([ATTRIBUTE_PREFIX + i for i in ATTRIBUTES_TO_MIRROR])
+
+
+def mirror_resource(input_filename, output_filename):
+  """Convert LTR resource to RTL android resource. (or the other way around)
+
+  For example,
+  from paddingLeft="10dp" to paddingRight="10dp"
+  from gravity="right|center_vertical" to gravity="left|center_vertical"
+  """
+
+  tree = ET.parse(input_filename)
+  for element in tree.iter():
+    attribute_names = ATTRIBUTES_TO_MIRROR.intersection(element.keys())

[newt (away), 2013/04/26 18:46:26]

if this file changes to convert RTL-friendly layouts into LTR-only layouts (e.g.
paddingStart -> paddingLeft), then we could check for "illegal" attributes here.
e.g. make sure that the input files don't contain paddingLeft or paddingRight.

+    mirrored_attributes = {}
+    for attribute_name in attribute_names:
+      if 'Left' in attribute_name:
+        mirrored_attribute_name = attribute_name.replace('Left', 'Right')
+        mirrored_attribute_value = element.attrib[attribute_name]
+      elif 'Right' in attribute_name:
+        mirrored_attribute_name = attribute_name.replace('Right', 'Left')
+        mirrored_attribute_value = element.attrib[attribute_name]
+      else:
+        # This is either gravity or layout_gravity
+        mirrored_attribute_name = attribute_name
+        mirrored_attribute_value = re.sub('left|right',
+            lambda x: 'right' if x.group(0) == 'left' else 'left',
+            element.attrib[attribute_name])
+
+      mirrored_attributes[mirrored_attribute_name] = mirrored_attribute_value
+      # Delete the attribute that we are going to mirror.
+      del element.attrib[attribute_name]
+
+    # Update the parsed xml with the mirrored attributes.
+    element.attrib.update(mirrored_attributes)
+
+  build_utils.MakeDirectory(os.path.dirname(output_filename))
+  tree.write(output_filename, encoding='utf-8', xml_declaration=True)
+
+
+def mirror_resources_in_dir(input_dir, output_dir):
+  for root, dirs, files in os.walk(input_dir, followlinks=True):
+    relative_dir = os.path.relpath(root, input_dir)
+    for file_name in files:
+      if file_name.lower().endswith('.xml'):
+        input_filename = os.path.join(input_dir, relative_dir, file_name)
+        output_filename = os.path.join(output_dir, relative_dir, file_name)
+        mirror_resource(input_filename, output_filename)
+
+
+def ParseArgs():
+  """Parses command line options.
+
+  Returns:
+    An options object as from optparse.OptionsParser.parse_args()
+  """
+  parser = optparse.OptionParser()
+  parser.add_option('--res-dir',
+                    help='directory containing resources to be mirrored to RTL')
+  parser.add_option('--res-mirrored-dir',
+                    help='directory containing RTL resources to be generated')
+
+  (options, args) = parser.parse_args()
+
+  if args:
+    parser.error('No positional arguments should be given.')
+
+  # Check that required options have been provided.
+  required_options = ('res_dir', 'res_mirrored_dir')
+  build_utils.CheckOptions(options, parser, required=required_options)
+  return options
+
+
+def main(argv):
+  """Convert Android LTR xml resources to RTL and save it to -ldrtl directories.
+
+  Please refer to the function mirror_resource's comment on how the files
+  are mirrored.
+
+  ldrtl directory is explained at
+  http://developer.android.com/guide/topics/resources/providing-resources.html
+  """
+  options = ParseArgs()
+
+  res_sub_dirs = os.walk(options.res_dir).next()[1]
+
+  for res_sub_dir in res_sub_dirs:
+    # If the directory has already RTL resources, we don't need to mirror. Skip.
+    if '-ldrtl' in res_sub_dir:
+      continue
+
+    # We only mirror resources under layout*/ or xml*/.
+    if (res_sub_dir.startswith('layout') or res_sub_dir.startswith('xml')):
+      # Insert ldrtl to the dir name.
+      # For example, from layout-hdpi to layout-ldrtl-hdpi.
+      res_sub_dir_split = res_sub_dir.split('-')
+      res_sub_dir_split.insert(1, 'ldrtl')
+      res_mirrored_sub_dir = '-'.join(res_sub_dir_split)
+      # Mirror all the resource files.
+      mirror_resources_in_dir(
+          os.path.join(options.res_dir, res_sub_dir),
+          os.path.join(options.res_mirrored_dir, res_mirrored_sub_dir))
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))
+