how to destroy a layout before we rebuild it Qt c++ - c++

Question

I have a little problem displaying my layouts. I have an application that contains a GridLayout, HBoxLayout, and VBoxLayout.
The HBoxLayout contains: a button and line edit
The GridLayout contains: progbars (1-99)
The HBoxLayout and the GridLayout are put in a VBoxLayout
My problem is when I click, The grid layout appears on the HBoxLayout. It's like the HBoxLayout wasn't a part of the VBoxLayout. So, even when I destroy the layout and create it again, I still have the same problem.
An image is displayed below to better understand my problem.
code: window.cpp
Window::Window(QWidget *parent) :
QWidget(parent){
label = NULL;
progressbar = NULL;
workerThread = NULL;
m_counter = NULL;
layout = new QHBoxLayout(NULL);
lineEdit = new QLineEdit(NULL);
m_button = new QPushButton("click", NULL);
time= new QTimer(this);
lineEdit-> setInputMask("00");;
//lineEdit->setGeometry(400,10,160,30);
lineEdit->setPlaceholderText("N between 1 & 99");
// Create and position the button
// m_button->setGeometry(100, 10, 150, 30);
QIcon icon("/home/ca/Downloads/chauvin.png");
m_button->setIcon(icon);
m_button->setIconSize(QSize(100, 30));
m_button->setToolTip("this is a beautifull button ");
//layout = new QFormLayout;
layout->addWidget(m_button);
layout->addWidget(lineEdit);
setLayout( layout );
// showTime();
time->start(1000);
setWindowTitle(tr("Digital Clock"));
// NEW : Do the connection
connect(m_button, &QPushButton::pressed, this , &Window::slotButtonPressed);}
void Window::slotButtonPressed(){
layoutgrid = new QGridLayout(NULL);
m_button->setEnabled(true);
QString contenu = lineEdit->text();
int i_contenunumber= contenu.toInt(0,10);
m_counter= new int[i_contenunumber];
memset( m_counter, 0, i_contenunumber );
label = new QLabel*[ i_contenunumber ];
progressbar = new QProgressBar*[ i_contenunumber ];
workerThread= new mythread*[ i_contenunumber ];
int x= 0;
int y= -1;
int i=0;
m_button->setText("Checked");
for(i=0;i< i_contenunumber ;i++)
{
if (i%5==0)
{
x=0;
y++;
}
int i_Randomvalue = rand() % 500 + 100;
// label[i] = new QLabel(NULL);
// //label[i]->setGeometry(100*x*1.7, 80+(50*y), 160, 30);
// label[i]->setText("Tread" + QString::number(i_Randomvalue));
// label[i]->setVisible(true);
progressbar[i] = new QProgressBar(NULL);
progressbar[i]->setRange(0, 100);
progressbar[i]->setOrientation(Qt::Horizontal);
//progressbar[i]->setGeometry(100*x*1.7,60+(50*y),150,30);
progressbar[i]->setValue(0);
progressbar[i]->setVisible(true);
layoutgrid->addWidget(progressbar[i],y,x);
setLayout(layoutgrid);
workerThread[i] = new mythread(i_Randomvalue, i);
connect(workerThread[i], &mythread::signalemit, this, &Window::barprogress);enter code here
connect(workerThread[i], &mythread::signalFinThread, this, &Window::findethread);
workerThread[i] ->start();
x++;
m_counter[i]=0;
}
// Window::setFixedSize(1000,120+(50*y-1));
removeLayout();
layoutvbox = new QVBoxLayout(NULL);
layoutvbox->addLayout(layout);
layoutvbox->addLayout(layoutgrid);
setLayout(layoutvbox);
adjustSize();
}
void Window::removeLayout ( void )
{
QLayout* po_l_layout = QWidget::layout ();
if (po_l_layout != 0)
{
QLayoutItem *item;
while ((item = po_l_layout->takeAt(0)) != 0)
po_l_layout->removeItem (item);
delete po_l_layout;
}
}

Answer 1

delete layout will not work here because it will not delete all the containing widgets
Instead just create a new widget that contains the layout
m_widget = new QWidget();
QGridLayout *outerLayout = new QGridLayout(m_widget);
m_layout->addWidget(m_widget);
this->setLayout(m_layout);
to remove and rebuild just delete the widget
delete m_widget
deleting a widget deletes all sub layouts and widgets contained by the widget

Answer 2

Once the layout of your widget is set, you can not change it unless you remove the old layout. My suggestion is to delete the old layout
//remove all of layouts widgets here
delete layout
Then create the QVBoxLayout and call setLayout(layoutvbox)
If you wish to switch back and forth, just recreate/delete when needed.