The typical workflow when developing HTML forms usually is:
1. Edit the forms in your IDE
2. Copy and paste the content into the HTML forms of the Legacy Administration UI
3. Reload your form to test changes
It is however possible to automatically reload your forms as you edit them:
1. Enable uiframework development mode following the steps at https://wiki.openmrs.org/display/docs/Using+the+UI+Framework+in+Your+Module
2. When you access your forms, add "&definitionUiResource=definitionUiResource" to then end of your form so that the new url is:
Definition UI resource would be in the form: "pihcore:htmlforms/checkin.xml" where "pihcore" is the module name, and the form lives in the directory "omod/src/main/webapp/resources/htmlsforms"
NOTE: that it will *only* pick up new updates when opening a form in "ENTER" mode--it will attempt to load the form from the file system and then save any changes to the form definition in the DB. Loading in "EDIT" mode will load the form from the database, *without* checking the file system first.
Special thanks to Unknown User (mogoodrich) for the tip