Prevent user input via keyboard

This commit prevents the user from entering something into the text
field as this could currently lead to an exception

Change-Id: I30cb8c0846c93a82119cfb54dc6e2fe76df23d4c
1 file changed
tree: 8852d5bb25e9e42bc4dcb4ab36a71c8e7eff9412
  1. org.eclipse.example.calc/
  2. org.eclipse.example.calc.test/
  3. pom.xml