Why is this error: reference to ‘statusBar’ is ambiguous.. coming? Is this a bug?

[spirit]

try this

...
this->statusBar()->showMessage(tr("File successfully loaded."), 3000);
...

...
this->statusBar()->showMessage(tr("File successfully loaded."), 3000);
...

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looks like you have a member in Ui_MainWindow which is named as statusBar.