How to can I upgrade Xcode 4.1 to 4.5.2 properly? I'm trying to get Xcode up to date... but i think i have a little problem.

I go in the Mac App Store. I find Xcode. I click on free button, it asks me to connect with my Apple-ID. Done.

I get the "install" button... I click and nothing happens. I have a loader spinning during few seconds at the right of buttons Prev/Next in the top bar... but nothing else.

Where is a process bar ? Mac App says to me that Xcode takes 1.50 GB but is downloading ? How can I follow the download ? Is really downloading ? Do I have to uninstall the Xcode 4.1 ?

I am a bit lost with the changes to this program and the new App Store.
Setting aside whether you are actually done with the prior version of Xcode (as older versions have some capabilities and older SDK that the newer versions no longer support - you might want to keep an old machine with an old Xcode around if you are supporting legacy software products - but let's assume you don't care about anything other than making new programs with the newest Xcode) let's dive in with the steps.

To prepare for the new Xcode, it is easiest to uninstall all previous versions of Xcode by following the uninstall documentation for each version you have installed.

For Xcode 4.1 you will want to run the perl script to clean things up:

Uninstalling Xcode Developer Tools

To uninstall Xcode developer tools on the boot volume along with the  directory, from a Terminal window type:

$ sudo &lt;Xcode&gt;/Library/uninstall-devtools --mode=all




For the new Xcode, the App Store doesn't normally show the download progress so you must track it from Launchpad or just by watching the /Applications folder in Finder. It shows INSTALLING as depicted above, but the Launchpad view has a live progress bar and summary of the 1.61 GB download as depicted below.