Please help me to check this simple project,thanks!

[spirit]

btw, fix you connection, it should look like

...
connect(calendar,SIGNAL(activated(const QDate&)),this,SLOT(setlineeditdate(const QDate&)));
...

...
connect(calendar,SIGNAL(activated(const QDate&)),this,SLOT(setlineeditdate(const QDate&)));
...

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