Hi Sheila!
Please don't despair! Truly, rain every day is typical for the subtropical climate of Central Florida! Thankfully, this usually means a nice shower every afternoon which cools everything off, then the skies return to their usual glorious sunny blue! An added bonus to this daily shower is that it often clears the Parks out a bit, and leaves the lines shorter for the attractions once it is over! Our family handles rain by either buying/bringing rain ponchos and continuing to enjoy the attractions that remain open, finding a nice place to sit down and enjoy our lunch or snack, or heading to the shops on Main Street, U.S.A. Our family motto has become "Rain is NOT a factor!!!"
However, if by some chance it rains and pours the entire time you are in Florida, then just keep your sense of humor intact, pull on the ponchos, and go for it! In July it will still be warm in Florida, even during the storms. As long as it is not lightning, they will keep most of the attractions in operation. And of course, you can always go ahead and swim when it rains, if it's not a thunderstorm - you might get wet, but most people don't let that bother them! (haha)
Another suggestion is to head to Downtown Disney Area to try out
DisneyQuest Indoor Interactive Theme Park, or catch a movie at the AMC Downtown Disney 24!
I hope you all have a magical time, and remember, "Rain is NOT a factor!!!"