Effecinecy for a GU Interface

[salmanmanekia]

I have written a piece of code which has layouts ,buttons ,labels and i have defined them as follows

read->setFixedHeight(30);
read->setFixedWidth(100);

setGrid->setFixedHeight(30);
setGrid->setFixedWidth(100);

run->setFixedHeight(30);
run->setFixedWidth(210);

gridLayout->addLayout(formLayout,0,0,10,10,Qt::AlignLeft);
gridLayout->addWidget(read,20,0,5,5,Qt::AlignLeft);
gridLayout->addWidget(setGrid,20,5,5,5,Qt::AlignLeft);
gridLayout->addWidget(run,30,0,10,10,Qt::AlignLeft);

my question is that if i change one of the value of the parameter then my whole design is out of shape...as it is quite obvious why ?,my question is that is there any other way to define these and not hard code it...Thanks