Spacing between widgets in QHBoxLayout - c++

Question

I'm trying to create a GUI with QtCreator. For this GUI, I need to display several images with different sizes next to each other. These images should be touching each other.
I use a QWidget with a QHBoxLayout, where I add the labels (with different sizes) containing the images.
According to related questions, I should use setSpacing and setContentsMargin to remove these spaces, but that won't work; I tried several times.
Here's the code:
QWidget *widget = new QWidget(ui->tagcloud);
QHBoxLayout * l = new QHBoxLayout(widget);
ui->tagcloud->setWidget(widget);
for(int i=0;i<list.size();++i)
{
QLabel *lab = new QLabel;
QPixmap pic((list[i].imgPath).c_str()); //This fetches the image
int sizeChange = 50 + (2*list[i].percent); //Calculates the size of the image
lab->setFixedSize(QSize(sizeChange, sizeChange));
lab->setPixmap(pic);
lab->setScaledContents(true);
l->addWidget(lab);
l->setSpacing(0);
}
However, when I run this, the spacing remains the same (i.e. definitely not zero).
If I add more labels to the layout, the spacing seems to get smaller.
Can anyone explain or help me? Thanks!

Answer 1

Setting spacing to 0 and adding stretch before and after works for me :
l->addStretch();
for(int i = 0; i < list.size(); ++i)
{
QLabel *lab = new QLabel;
QPixmap pic((list[i].imgPath).c_str()); //This fetches the image
int sizeChange = 50 + (2*list[i].percent); //Calculates the size of the image
lab->setFixedSize(QSize(sizeChange, sizeChange));
lab->setPixmap(pic);
lab->setScaledContents(true);
l->addWidget(lab);
}
l->addStretch();
l->setSpacing(0);
Also this works I think
l->setSizeConstraint(QLayout::SetMaximumSize);