Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Cannot hide QtQuick.TableView columns



  • The documentation for TableView suggests using TableView.contentWidthProvider to return 0 to hide columns. However, this is incorrect as the code ignores a width of zero providing some default width, and complains with:

    QML TableView: columnWidthProvider did not return a valid width for column: 2

    Setting visible: false in the delegate also does not seem to work, even when a valid width (for example 1px) is specified. What is the proper way to hide columns in QtQuick.TableView?



  • I put together a simple example to demonstrate this problem and found that TableView does indeed honor columnWidthProvider returning a value of zero, as documented. That means there is a problem in my code.

    I'll report back here once I figure it out.

    main.cpp

    #include <QGuiApplication>
    #include <QQmlApplicationEngine>
    #include "tablemodel.h"
    
    int main(int argc, char *argv[])
    {
        QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
        QGuiApplication app(argc, argv);
        QQmlApplicationEngine engine;
    
        qmlRegisterType<TableModel>("TableModel", 1, 0, "TableModel");
    
        const QUrl url(QStringLiteral("qrc:/main.qml"));
        QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
                         &app, [url](QObject *obj, const QUrl &objUrl) {
            if (!obj && url == objUrl)
                QCoreApplication::exit(-1);
        }, Qt::QueuedConnection);
    
        engine.load(url);
    
        return app.exec();
    }
    

    tablemodel.h

    #ifndef TABLEMODEL_H
    #define TABLEMODEL_H
    
    #include <QAbstractTableModel>
    
    class TableModel : public QAbstractTableModel
    {
        Q_OBJECT
    
    public:
        explicit TableModel(QObject *parent = nullptr);
    
        // Header:
        QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
    
        // Basic functionality:
        int rowCount(const QModelIndex &parent = QModelIndex()) const override;
        int columnCount(const QModelIndex &parent = QModelIndex()) const override;
    
        QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
    
    private:
    };
    
    #endif // TABLEMODEL_H
    

    tablemodel.cpp

    #include "tablemodel.h"
    #include <QtQml>
    
    
    TableModel::TableModel(QObject *parent)
        : QAbstractTableModel(parent)
    {
    }
    
    QVariant TableModel::headerData(int section, Qt::Orientation orientation, int role) const
    {
        Q_UNUSED(orientation);
        Q_UNUSED(role);
        return QString("Column %1").arg(section);
    }
    
    int TableModel::rowCount(const QModelIndex &parent) const
    {
        if (parent.isValid())
            return 0;
    
        return 100;
    }
    
    int TableModel::columnCount(const QModelIndex &parent) const
    {
        if (parent.isValid())
            return 0;
    
        return 10;
    }
    
    QVariant TableModel::data(const QModelIndex &index, int role) const
    {
        Q_UNUSED(role);
    
        if (!index.isValid())
            return QVariant();
    
        return QString("Cell %1, %2").arg(index.row()).arg(index.column());
    }
    
    //qmlRegisterType<TableModel>("com.vedanamedia.TableModel", 1, 0, "TableModel");
    

    main.qml

    import QtQuick 2.13
    import QtQuick.Window 2.13
    import TableModel 1.0
    
    Window {
        visible: true
        width: 640
        height: 480
        title: qsTr("Hello World")
    
        TableView {
            anchors.fill: parent
            model: TableModel { }
            columnWidthProvider: function(col) {
                if(col % 2 == 0) {
                    return 0;
                } else {
                    var nShownColumns = 0
                    for(var i=0; i < model.columnCount(); i++) {
                        if(i % 2 != 0) {
                            nShownColumns++;
                        }
                    }
                    return width / nShownColumns;
                }
            }
            contentWidth: width
            onWidthChanged: {
                if(contentWidth > 0) // prevent crash (Qt bug)
                    forceLayout()
            }
            delegate: Rectangle {
                implicitWidth: 100
                implicitHeight: 50
                Text {
                    anchors.centerIn: parent
                      text: display
                }
                Rectangle { // border-left
                    width: 3
                    height: parent.height
                    color: 'green'
                }
                Rectangle { // border-right
                    width: 3
                    height: parent.height
                    x: parent.width-3
                    color: 'red'
                }
            }
        }
    }
    


  • @patrickkidd said in Cannot hide QtQuick.TableView columns:

    I put together a simple example to demonstrate this problem and found that TableView does indeed honor columnWidthProvider returning a value of zero, as documented. That means there is a problem in my code.

    Aha! This is fixed in Qt-5.13.0. My dev build was using 5.12.4 which is why I was getting the bug. I was running my test example against 5.13.0, which shows that it I fixed.


Log in to reply