使用Model/View编程加载大量数据的正确姿势 - QTCN开发网

void BTUsrCtlWidget::initDeviceInfo()
{
    // 清空模型
    //
    mDeviceModel->clear();
    mDeviceView->clearSelection();
    mDeviceProxyModel->setSourceModel(nullptr);
    QItemSelectionModel *selectionModel = mDeviceView->selectionModel();
    mDeviceView->setModel(nullptr);
    if (selectionModel != nullptr)
    {
        if (selectionModel->parent() != nullptr)
        {
            selectionModel->deleteLater();
        }
        else
        {
            delete selectionModel;
            selectionModel = nullptr;
        }
    }

    mDeviceView->setUpdatesEnabled(false);

    // 分类信息
    //
    QStringList deviceTypeList;
    deviceTypeList << tr("Intercom Device") << tr("Video Device") << tr("VoIP")
        << tr("Broadcast Device") << tr("Monitor Device") << tr("Other Device");

    for (int i = 0; i < deviceTypeList.size(); i++)
    {
        QStandardItem *deviceTypeItem = new QStandardItem(deviceTypeList.at(i));
        deviceTypeItem->setForeground(QBrush(QColor(190, 197, 202)));
        deviceTypeItem->setData(ItemMark::MARK_DEVICE, Qt::UserRole);
        deviceTypeItem->setData(i+1, USER_ROLE_DEVICE_TYPE);
        deviceTypeItem->setToolTip(deviceTypeList.at(i));

        QStandardItem *deviceTypeCheckItem = new QStandardItem();
        deviceTypeCheckItem->setCheckable(true);

        mDeviceModel->setItem(i, 0, deviceTypeItem);
        mDeviceModel->setItem(i, 1, deviceTypeCheckItem);
    }

    // 加载数据
    //
    foreach (DepartmentUserInfo info, PttHelper.mDepartmentUserInfoList)
    {
        QStandardItem *deviceUserItem = new QStandardItem();

        // save data
        //
        QVariant var;
        var.setValue(info);
        deviceUserItem->setData(ItemMark::MARK_MEMBER, Qt::UserRole);
        deviceUserItem->setData(var, USER_ROLE_DEVICE_USER);

        // set foreground and icon
        //
        if (info.online == Offline)
        {
            deviceUserItem->setForeground(QBrush(QColor(88, 96, 106)));
            deviceUserItem->setIcon(AppHelper.getUserIcon(false, info.type));
        }
        else
        {
            deviceUserItem->setForeground(QBrush(QColor(190, 197, 202)));
            deviceUserItem->setIcon(AppHelper.getUserIcon(true, info.type));
        }

        // set user name
        //
        QString displayName = AppHelper.displayName(info.name, info.account);
        deviceUserItem->setText(displayName);
        deviceUserItem->setToolTip(displayName);

        // setCheckState
        //
        QStandardItem *deviceUserCheckItem = new QStandardItem();
        deviceUserCheckItem->setCheckable(true);

        // add user to tree
        //
        for (int i = 0; i < mDeviceModel->rowCount(); i++)
        {
            QStandardItem *deviceTypeItem = mDeviceModel->item(i, 0);
            if ((deviceTypeItem != nullptr) && (deviceTypeItem->data(USER_ROLE_DEVICE_TYPE).toInt() == info.type))
            {
                int rowNumber = deviceTypeItem->rowCount();
                deviceTypeItem->setChild(rowNumber, 0, deviceUserItem);
                deviceTypeItem->setChild(rowNumber, 1, deviceUserCheckItem);

                break;
            }
        }

        QApplication::processEvents();
    }

    mDeviceProxyModel->setSourceModel(mDeviceModel);
    mDeviceView->setModel(mDeviceProxyModel);
    mDeviceModel->setColumnCount(2);
    mDeviceView->setColumnWidth(0, 205);
    mDeviceView->setUpdatesEnabled(true);
}