QGridLayout动态添加控件

QGridLayout* lay = new QGridLayout();
int total = paras.size();
int colum = 4;
for(int i=0; i<total; i++){
　　Zparam* pZparam = new Zparam(this);
　　m_params.push_back(pZparam);
　　lay->addWidget(pZparam, i/colum, i%colum);
}
this->setLayout(lay);

delete this->layout();
for(int i=0; i<(int)m_params.size(); i++){
    delete m_params[i];
}
m_params.clear();