In my Android app I use a TableView as the main view with a list of items; the rightrectangle has been customized to display 4 labels each, two with text and two with colors.
My apologies, I didn't realize that the TableViewItemCustomize event fires when you return from the detail screen. I have a lot of code there for customizing the display. However it executes very quickly even in debug mode.
What should be the parent of this paintbox? One of the contained rectangles like rightrectangle? Or the Item rectangle itself? Why the paint box? Is it faster? How do I know I won't have the same performance issues with the paintbox?
What about using a TTMSFMXHTMLText object, one per row, and drawing an HTML table? Would that be just as slow, or faster but still too slow?
If you do not need HTML, I would suggest to only use one TText element or TLabel and then add a multiline text separated with #13#10. The slowness is most likely created due to the already high number of elements inside a single item. It's inclear if the performance increases if you use a single TTMSFMXHTMLText, it depends on the amount of information and text. The TTMSFMXHTMLText already switch automatically to a TText rendering, if there are no HTML tags detected so you could safely use a TTMSFMXHTMLText, but use the #13#10 instead of the <br> tags for multiple lines.