remove local.properties, and add a script, run from build.xml before

local.properties is loaded, to generate it with a path to sdk
appropriate to the installation.

xwords4/android/XWords4/.gitignore

@@ -1,5 +1,6 @@
-XWords4.apk
+*.apk
 ant_out.txt
+local.properties
 bin
 gen
 libs

xwords4/android/XWords4/build.xml

@@ -4,6 +4,7 @@
     <!-- The local.properties file is created and updated by the 'android' tool.
          It contains the path to the SDK. It should *NOT* be checked in in Version
          Control Systems. -->
+    <exec dir=".." executable="./scripts/setup_local_props.sh" output="ant_out.txt" />
     <property file="local.properties" />
 
     <!-- The build.properties file can be created by you and is never touched
@@ -50,8 +51,6 @@
 
     <exec dir=".." executable="./scripts/genvers.sh" output="ant_out.txt" />
 
-
-
     <!-- Execute the Android Setup task that will setup some properties specific to the target,
          and import the build rules files.
 

xwords4/android/scripts/setup_local_props.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+echo "i am here"
+
+cd $(dirname $0)
+cd ../XWords4
+
+if [ ! -e local.properties ]; then
+    ANDROID="$(which android)"
+    SDK_DIR=$(dirname $ANDROID)
+    SDK_DIR=$(dirname $SDK_DIR)
+    echo "# generated by $0" > local.properties
+    echo "sdk.dir=$SDK_DIR" >> local.properties
+fi
+
+exit 0