Can't set QComboBox/QSlider margins

bibasmall

I'm creating a property editor with content placed in a QTreeView and I want my editors to have padding from the edge of the widget. I also use a delegate to create the editors dynamically. I used editorPtr->setContentsMargins and in case of QLineEdit it works as expected. But other editors seem to ignore the margins. How to properly set margins for these widgets?

Chris Kawa

@bibasmall put the layout on a dummy container widget e.g.

QWidget*     container = new QWidget(parent);
QHBoxLayout* pLayout   = new QHBoxLayout(container);
QLineEdit*   pLineEdit = new QLineEdit();

pLayout->addWidget(pLineEdit);
pLayout->setContentsMargins(0, 0, 5, 0);

pEditor = container;

mrjj

Hi
so editorPtr is pointing to a layout ?

All widgets should honor margins in its layout

Can you show the CreateEditor code for your Delegate ?

bibasmall

Hello. No, editorPtr is pointing to the editor. Here is my createEditor code:

QWidget* CEditorDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem&, const QModelIndex& index) const
{

auto editorType = CPropertiesTreeModel::GetEditorType(index);
QWidget* pEditor = nullptr;

if (editorType == EditorType::LineEdit)
{
	QLineEdit* pLineEdit = new QLineEdit(parent);
	//LineEdit is filled with data here
	pEditor = pTextEditor;
}
else if (editorType == EditorType::Combobox)
{
	QComboBox* pQComboBox = new QComboBox(parent);
	//ComboBox is filled with data here
	pEditor = pQComboBox;
}
else if (editorType == EditorType::Slider)
{
	auto optData = CPropertiesTreeModel::GetIndexPossibleValues(index);
	if (optData)
	{
		auto optEType = CPropertiesTreeModel::GetEditorValueType(index);
		if (optEType == EType::EInt)
		{
			CExtendedSlider* pExtSlider = new CExtendedSlider(Qt::Horizontal, parent);
                        //ExtSlider is filled with data here
			pEditor = pExtSlider;
		}
		else if (optEType == EType::EFloat)
		{
                        CFloatSlider* pFloatSlider = new CFloatSlider(Qt::Horizontal, parent);
			//FloatSlider is filled with data here
			pEditor = pFloatSlider;
		}
	}
}

if (pEditor)
	pEditor->setContentsMargins(0, 0, 5, 0);

return pEditor;

}

mrjj

@bibasmall
Hi
Ahh, QWidgets has setContentsMargins.

Seems Only LineEdit cares about it in its drawing/handling.
So Slider and Combo do not honor/use it.

I think you have to use a layout and its margins to make it work for all types of widgets.

bibasmall

Could you please tell me how should I add the layout in my code?
If I write:

QHBoxLayout* layout = new QHBoxLayout(parent);
layout->addWidget(pEditor);
layout->setContentsMargins(0, 0, 5, 0);

The layout will obviously not be placed in the corresponding cell, nor be deleted with the editor. If I change the layout's parent to pEditor, this code does nothing — even QLineEdit ignores margins in this case.

Chris Kawa

@bibasmall put the layout on a dummy container widget e.g.

QWidget*     container = new QWidget(parent);
QHBoxLayout* pLayout   = new QHBoxLayout(container);
QLineEdit*   pLineEdit = new QLineEdit();

pLayout->addWidget(pLineEdit);
pLayout->setContentsMargins(0, 0, 5, 0);

pEditor = container;

bibasmall

@Chris-Kawa thank you, it helped to set the margins!