How to use ant to build with android

Question

I want to set up a ant build for my project. I found a tutorial saying that I need to write the following command in order to prepare for ant build:

android update project -p 

then I get the result

Updated local.properties
Updated file ./proguard-project.txt
It seems that there are sub-projects. If you want to update them
please use the --subprojects parameter.

so If I try

android update project -p . --subprojects

then I get:

Updated local.properties
Updated file ./proguard-project.txt
Error: The project either has no target set or the target is invalid.
Please provide a --target to the 'android update' command.

and if I try

ant release

I get

sdk.dir is missing. Make sure to generate local.properties using 'android update project' or to inject it through an env var

Can some one please help me in setting up the project with ant. Thanks

Solution

I also had the same problem.
My problem problem got solved by the following command.

android update project --path . --subprojects --target android-19

ANT will automatically set your sdk.dir into correct one.
Don't put anything inside your local.properties.

# This file is automatically generated by Android Tools.
# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
#
# This file must *NOT* be checked into Version Control Systems,
# as it contains information specific to your local configuration.

# location of the SDK. This is only used by Ant
# For customization when using a Version Control System, please read the
# header note.

Comments

[neodymium]

I have my project.properties file with a line: target=android-18 and also have something similar to what you describe in the manifest.xml file, however I am getting the same message as the OP. "It seems that there are sub-projects. If you want to update them please use the --subprojects parameter."

[Dheeraj Vepakomma]

The target should be specified as: --target android-19.