problem with mouse press event inside a QGraphicsView

I have one QGraphicsScene which is being used by two different QGraphicsView. One of these view is a member of a QDialog class. we have reimplemented mousePressEvent of QDialog class. When i run my application and perform a left click in QDialog, it is coming inside mousePressEvent() of QDialog class. But when i perform any click (left or right) on second view and then perform left click on my QDialog, control is not coming inside mousePressEvent().
Right click on QDialog is working fine in both cases.

Can anyone help me with this issue?

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