How to decrease the size of cell inside the Qtreeview.

[Yash001]

I am placing widgets inside the Qtreeview using setindexwidget funcation.
I would like to reduce the space inside the cell where horizontally. (black dotted line box)

I have try to setitemDeligate but it does not work.

any one have idea?

[ChrisW67]

Where is the extra space? Inside the table cell but outside your custom widget, or inside your custom widget? How are you controlling the tree/table column widths?

Please provide at least some idea of what your code looks like.

[Yash001]

Remove space; Inside the table cell but outside my custom widget

Here some code snap. @ChrisW67

#include "ElementsListWidget.h"
#include "AbstractElement.h"
#include "ElementDragEventHandler.h"
#include <QAbstractScrollArea>
#include <QGridLayout>
#include <QLabel>
#include <QPixmap>
#include <QScrollArea>
#include <QSortFilterProxyModel>
#include <QVariant>
#include <qscrollbar.h>
#include <qstandarditemmodel.h>
#include <qtreeview.h>


ElementsListWidget::ElementsListWidget(QWidget* parent)
    : QWidget(parent)
{
    QVBoxLayout* mainlayout = new QVBoxLayout(this);
    mainlayout->setContentsMargins(0, 0, 0, 0);

    elementsListLayout = new QTreeView(this);
    elementsListLayout->setContentsMargins(0, 0, 0, 0);
    elementsListLayout->setHeaderHidden(true);
    elementsListLayout->setIndentation(0);
    elementsListLayout->setUniformRowHeights(false);
    elementsListLayout->setObjectName("ElementsListWidget");
    elementsListLayout->setSelectionMode(QAbstractItemView::NoSelection);

    elementsListLayout->verticalScrollBar()->parent()->setProperty("background_transparent", true);
    elementsListLayout->horizontalScrollBar()->parent()->setProperty("background_transparent", true);

    sourceModel = new QStandardItemModel(this);
    elementsListLayout->setModel(sourceModel);
    
    mainlayout->addWidget(elementsListLayout);
    setLayout(mainlayout);

    elementsPerRow = 3;
    totalModelElements = 0;
    sourceModel->setColumnCount(elementsPerRow);
}

void ElementsListWidget::addElement(AbstractElement* element)
{
    elementsModel << element;
    showWidgetOnView(createDisplayUnit(element));
}

QWidget* ElementsListWidget::createDisplayUnit(AbstractElement* element)
{

    if (!element) {
        return nullptr;
    }
        

    QWidget* elementDispalyWidget = new QWidget;
    elementDispalyWidget->setObjectName("elementDisplayUnit");

    QVBoxLayout* elementdisplayLay = new QVBoxLayout(elementDispalyWidget);
    //elementdisplayLay->setContentsMargins(0, 0, 0, 0);

    QLabel* elementIconLabel = new QLabel(elementDispalyWidget);
    elementIconLabel->setObjectName("elementIconLabel");
    elementIconLabel->setProperty("element", QVariant::fromValue(static_cast<AbstractElement*>(element)));
    elementIconLabel->setCursor(Qt::OpenHandCursor);
    elementIconLabel->setAlignment(Qt::AlignCenter);
    elementIconLabel->setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Maximum);
    elementIconLabel->installEventFilter(new ElementDragEventHandler(elementIconLabel)); // Install event filter
    elementIconLabel->setPixmap(element->getImage().scaled(50, 50));

    QLabel* elementNameLabel = new QLabel(element->getName(), elementDispalyWidget);
    elementNameLabel->setObjectName("elementNameLabel");
    elementNameLabel->setAlignment(Qt::AlignCenter);
    elementNameLabel->setWordWrap(true);

    elementdisplayLay->setAlignment(Qt::AlignHCenter);
    elementdisplayLay->addWidget(elementIconLabel);
    elementdisplayLay->addWidget(elementNameLabel);
    elementdisplayLay->addStretch();

    elementDispalyWidget->setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Maximum);

    return elementDispalyWidget;
}

void ElementsListWidget::setElementsPerRow(int numberOfelementsPerRow)
{
    if (numberOfelementsPerRow > 0) {
        elementsPerRow = numberOfelementsPerRow;
    }
}



void ElementsListWidget::serachElement(const QString& searchText)
{
    clearModel();

    // Iterate through the stored widgets in elementWidgetModel
    for (AbstractElement* element : elementsModel) {
        if (element && element->getName().contains(searchText, Qt::CaseInsensitive)) {
            showWidgetOnView(createDisplayUnit(element));
        }
    }

}

void ElementsListWidget::showWidgetOnView(QWidget* elementDisplayUnit)
{
    if (elementDisplayUnit == nullptr) {
        return;
    }

    QStandardItem* item = new QStandardItem;
    

    // Calculate the row and column count for the new element
    int row = totalModelElements / elementsPerRow;
    int column = totalModelElements % elementsPerRow;

    sourceModel->setItem(row, column, item);

    elementsListLayout->setIndexWidget(item->index(), elementDisplayUnit);

    totalModelElements++;
 }

void ElementsListWidget::clearModel() {
    sourceModel->clear();
    totalModelElements = 0;
 }

styel sheet for few widget

QWidget#ElementsListWidget {
	background-color: #DAE0E9;
	color: #3B5571;
	border: none;
}

#elementDisplayUnit {
	background-color: transparent;
	font-size: 14px;
}
#elementIconLabel {
	width: 64px;
	background-color: #ffffff;
    border: 1px solid #BEC9CD;
    height: 64px;
    position: relative;
    /* align-items: center; */
    border-radius: 5px;
    /* justify-content: center; */
    background-color: #FFFFFF;
}
#elementIconLabel:hover {
    background-color: lightgray;
}
#elementNameLabel {
    padding: 0px 0 0 0;
    font-size: 11px;
    max-width: 64px;
    text-align: center;
    line-height: 12px;
    /* text-overflow: ellipsis; */
	background-color: transparent;
    /* word-wrap: break-word; */
	font-weight: bold; 
}