If you try to clear your trash and it progress bar seems to hang, it’s probably due to a locked file. A few recommendations on the internet requires the user to mess around in terminal and creating a new .Trash2 folder in your home folder and than doing a mv and then delete again.
There’s an easier way to accomplish this. Simply go to your Trash, hit cmd-a, move all the files out into a temporary folder. The remaining ones in Trash will be the locked files.
To unlock, simply right click, Get Info, there should be a small lock on the bottom right of the pop up. Click on it to unlock the file. You should be able to delete it now.