Go in the “Project” part on the left of QtCreator and then in the “Run Settings” tab. There is a Arguments line edit where you can put all you need to pass to your app when launching it.
For Qt Creator from Qt 5.6
Go in the “Projects part on the left and then in the “Build & Run” tab. Here you have a “Command line arguments” edit where you can put all parameters you want to pass to your app.