Tips & Tricks for your 4D Apps – September Edition

by Add Komoncharoensiri, Director of Technical Services at 4D Inc

Here we go with another set of tips and tricks.

As you know, 4D Knowledge Base is a library of information about 4D technology where weekly tech tips and monthly tech notes are actively published. If you missed the last tips on the KB, that’s fine; here is a compilation from the past few weeks.

This blog post covers 16 tips:

• Upgrade old applications incrementally
• Table field data entry controls properties can be found in .4DCatalog file in project mode
• Quick File Creation Locations
• Unable to Switch Back to Design Mode from Application Mode
• Handling print jobs in headless mode 
• Run new HTTP requests in the Application process to trigger callbacks 
• Current Table Form Error Loop 
• A quick search for method dependencies 
• Assure to declare parameter $1 in 4DAction method to avoid web server error 500
• Maintaining Tables with Many Deletes and Creates
• Modify HTTPRequest default callback functions
• Moving a block of code up or down within the method editor
• Application Mode Is Not Accessible
• When to use simple objects vs. cs.className objects in HTTPRequest
• Checking whether 4D is successfully running in headless mode
• Utility method for converting a character to an HTML Entity Number