The problem with the display of QListWidget

[whyisosad]

There is a QListWidget in my program and there are many QListWidgetItem. The ViewMode is IconView. I want to change the text of the item dynamically. But when I change the text, the original text of the item is still display in the QListWidget. How can I solve this problem? And how can I align the items vertically and horizontally?

[jpn]

May we see some code how do you change the text?