The Formatter Preferences page allows you to set the editor's Tab policy.
The Formatter Preferences Preferences page is accessed from Window | Preferences | PHP | Formatter Preferences .

Select whether Tabs will be set by using Tabs or Spaces by selecting the required options from the drop-down Tab policy list.
If you selected Spaces, set the indentation size.
To apply Formatter Preferences settings to a specific project only:
- Select the link labelled "Configure Project Specific Settings".
- Select the required project from the list. A Formatter Preferences Properties dialog will appear.
- Select the required settings and click Apply. A prompt dialog will appear stating that a rebuild of the project must occur for the settings to take effect.
- Click Yes to rebuild the project. -Or- Click No for a rebuild to be performed only when PDT is restarted. -Or- Click Cancel to cancel the operation.