MAC :Button's name shows different when zoom application's window on desktop.

Steps:
1. In Creator go to 'File'->'New File or Project'
2.Create 'Qt Quick Application (Symbian Components)" with default settings.
3. Open designer ,add an "Button",give it a name"123456"
4. Run project target on Desktop

Excepted result:
The button should be show with a name"123456"

Actually result:.
Button shows with a name"1234..." at the begining, but if u zoom the window of this app,sometimes it shows"1234...",sometimes shows"123456"