Help creating a tree that traverses the map of a graph

[Trayon]

It's saying I don't have enough privileges to upload it. Perhaps a security measure? I suppose I'll post the full code. I know that the code will most likely have other errors though. Here goes:

(.pro file is already up)
main.cpp

#include <QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
//#include <QModelIndex>
#include <QFile>
#include <QDebug>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

protected:
    void keyPressEvent(QKeyEvent *);
    void keyReleaseEvent(QKeyEvent *);

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

MainWindow.cpp:

#include "mainwindow.h"
#include "treemapmodel.h"
#include "ui_mainwindow.h"
#include <QKeyEvent>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    QFont font;
    font.setFamily("Source Code Pro");
    font.setFixedPitch(true);
    //font.setPointSize(10);
    font.setPointSizeF(11.3);
    ui->textEdit->setFont(font);

    QFile somefile("../mainwindow.cpp");

    if(!somefile.open(QFile::ReadOnly| QFile::Text))
    {
        qDebug() << "not open";
    }

    QTextStream in(&somefile);
    ui->textEdit->setText(in.readAll());

//    QTextEdit *testTextEdit = new QTextEdit(this);
//    ui->verticalLayout->addWidget(testTextEdit);
}

void MainWindow::keyPressEvent(QKeyEvent *event)
{
    if(event->key() == Qt::Key_Escape) {
        ui->textEdit->setText("You pressed ESC");
    } else if(event->key() == Qt::Key_Alt) {

    }
}

void MainWindow::keyReleaseEvent(QKeyEvent *event)
{
    if(event->key() == Qt::Key_A) {
        ui->textEdit->setText("You released A");
    } else if(event->key() == Qt::Key_Alt) {

    }
}


MainWindow::~MainWindow()
{
    delete ui;
}

TreeMap.h:

#ifndef TREEMAP_H
#define TREEMAP_H
#include <QString>
#include <QVector>

class TreeMap
{
public:
    TreeMap(QString name, TreeMap *parentNode = 0);
    ~TreeMap();

    TreeMap nodeAt(int position) const;
    int nodeCount() const;
    QString data() const;
    bool insertNode(int position);
    TreeMap* getParent();
    bool removeNode(int position);
    int nodeIndex() const;
    bool setData(const QString &value);

private:
    QString nodeName;
    QVector<TreeMap> nodes;
    TreeMap *parent;
};

#endif // TREEMAP_H

TreeMap.cpp

#include "treemap.h"

TreeMap::TreeMap(QString name, TreeMap *parentNode = 0)
{
    parent = parentNode;
    nodeName = name;
}

TreeMap::~TreeMap(QString name, TreeMap *parentNode = 0)
{
    qDeleteAll(nodes);
}

TreeMap TreeMap::nodeAt(int position) const
{
    return nodes[position];
}

int TreeMap::nodeCount() const
{
    return nodes.length();
}

int TreeMap::nodeIndex() const
{
    if (parent)
        return parent->nodes.indexOf(const_cast<TreeItem*>(this));

    return 0;
}

QString TreeMap::data() const
{
    return nodeName;
}

bool TreeMap::insertNode(int position)
{
    if (position < 0 || position > nodes.length())
        return false;

    nodes.append(new TreeMap("", this));

    return true;
}

bool TreeMap::removeNode(int position)
{
    if (position < 0 || position > nodes.length())
        return false;

    nodes.remove(position,1);

    return true;
}

bool TreeMap::setData(QString &value)
{
    if (position < 0 || position > nodes.length())
        return false;

    nodeName = value;

    return true;
}

TreeMap* TreeMap::getParent()
{
    return parent;
}

TreeMapModel.h:

#ifndef TREEMAPMODEL_H
#define TREEMAPMODEL_H
#include <QAbstractItemModel>
#include <QModelIndex>
#include <QVariant>

class TreeMap;

class TreeMapModel : public QAbstractItemModel
{
    Q_OBJECT

public:
    TreeMapModel();
    ~TreeMapModel();

    // Defines for read:
    QString data(const QModelIndex &index, int role = Qt::DisplayRole);
    QString headerData() const override;

    QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override;
    QModelIndex parent(const QModelIndex &index) const override;

    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
    int columnCount(const QModelIndex &parent = QModelIndex()) const override{return 1;}

    Qt::ItemFlags flags(const QModelIndex &index) const override;
    // Defines for write:
    bool setData(const QModelIndex &index, const QString &value, int role = Qt::EditRole) override;
    bool setHeaderData(int section, Qt::Orientation orientation, const QVariant &value, int role = Qt::EditRole) override;

    bool insertRow(int position, const QModelIndex &parent = QModelIndex()) override;
    bool removeRow(int position, const QModelIndex &parent = QModelIndex()) override;


private:
    TreeMap rootNode;
    TreeMap *getItem(const QModelIndex &index) const;
};

#endif // TREEMAPMODEL_H

TreeMapModel.cpp:

#include "treemap.h"
#include "treemapmodel.h"

TreeMapModel::TreeMapModel()
{
    rootNode = new TreeMap("Root");
}

TreeMapModel::~TreeMapModel()
{
    delete rootNode;
}

QVariant TreeMapModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();

    if (role != Qt::DisplayRole && role != Qt::EditRole)
        return QVariant();

    TreeMap *node = getItem(index);

    return node->data();
}

TreeMap *TreeMapModel::getItem(const QModelIndex &index) const
{
    if (index.isValid()) {
        TreeMap *item = static_cast<TreeMap*>(index.internalPointer());
        if (item)
            return item;
    }

    return rootNode;
}

Qt::ItemFlags TreeMapModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return 0;

    return Qt::ItemIsEditable | QAbstractItemModel::flags(index);
}

QModelIndex TreeMapModel::index(int row, int column, const QModelIndex &parent) const
{
    if (parent.isValid() && parent.column() != 0)
        return QModelIndex();

    TreeMap*parentItem = getItem(parent);

    TreeItem *childItem = parentItem->nodeAt(row);
    if (childItem)
        return createIndex(row, column, childItem);
    else
        return QModelIndex();
}
bool TreeMapModel::insertRow(int position, const QModelIndex &parent)
{
    TreeMap *parentItem = getItem(parent);
    bool success;
    beginInsertRows(parent, position, position);
    success = parentItem->insertNode(position);
    endInsertRows();

    return true;
}

bool TreeMapModel::removeRow(int position, int rows, const QModelIndex &parent)
{
    TreeMap *parentItem = getItem(parent);
    bool success = true;

    beginRemoveRows(parent, position, position);
    success = parentItem->removeNode(position);
    endRemoveRows();

    return success;
}

QModelIndex TreeMapModel::parent(const QModelIndex &index) const
{
    if (!index.isValid())
        return QModelIndex();

    TreeMapModel *childItem = getItem(index);
    TreeMapModel *parentItem = childItem->getParent();

    if (parentItem == rootNode)
        return QModelIndex();

    return createIndex(parentItem->nodeCount(), 0, parentItem);
}

int TreeMapModel::rowCount(const QModelIndex &parent) const
{
    TreeMap *parentItem = getItem(parent);

    return parentItem->nodeCount();
}

bool TreeMapModel::setData(const QModelIndex &index, const QVariant &value, int role)
{
    if (role != Qt::EditRole)
        return false;

    TreeMapModel *item = getItem(index);
    bool result = item->setData(0, value);

    if (result)
        emit dataChanged(index, index);

    return result;
}


QString TreeMapModel::headerData() const override {return "";}

[SGaist]

You forgot a start before rootNode in the declaration.

[jsulm]

@Trayon @SGaist means you forgot a star (*) in front of rootNode in its declaration.

[Trayon]

Thanks for that catch, but it wasn't the error.

invalid use of incomplete type ‘class QAbstractItemModel’

If I uncomment the #define<QModelIndex> in the MainWindow class, the error originates from there (though the location is in the qabstractitemmodel.h file), and when I comment it, it comes from TreeMapModel.h

[SGaist]

Sorry but I'm going to be blunt: start by cleaning up your code.

It's full of errors:

• Wrong signatures for function you want to override
• You are trying to override non-virtual methods
• Wrong type used
• You have default values in methods implementation signatures
• You want to use a QVector on a type that doesn't match the requirements to be stored in a QVector or your QVector variable declaration is wrong.
• Mismatch of function signature between declaration and implementation
• You are using undeclared variables.

[Trayon]

I mostly left them in there for the sake of thoroughness. I know those other errors have nothing to do with it. I created a new widget project. It has the very basic default implementation. The only difference is the include for QModelIndex (I tried QAbstractItemModel and their combinations to no avail). So here are the only 2 files worth posting:

ShowError.pro

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = ShowError
TEMPLATE = app

DEFINES += QT_DEPRECATED_WARNINGS

SOURCES += \
        main.cpp \
        mainwindow.cpp

HEADERS += \
        mainwindow.h

FORMS += \
        mainwindow.ui

MainWindow.h:

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QModelIndex>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

And the result always yields:

In file included from /home/chris/Qt5.9.2/5.9.2/gcc_64/include/QtCore/QAbstractItemModel:1:0,
from ../ShowError/mainwindow.h:5,
from ../ShowError/main.cpp:1:
/home/chris/Qt5.9.2/5.9.2/gcc_64/include/QtCore/qabstractitemmodel.h:174:41: error: expected ‘)’ before ‘’ token
explicit QAbstractItemModel(QObject parent = Q_NULLPTR);
^

[SGaist]

Did you modify that header at some point ?

[Trayon]

Nope. (posts need at least 8 characters)

[mrjj]

@Trayon

And your header also looks like this at line 174 ?

class Q_CORE_EXPORT QAbstractItemModel : public QObject
{
    Q_OBJECT

    friend class QPersistentModelIndexData;
    friend class QAbstractItemViewPrivate;
    friend class QIdentityProxyModel;
public:

    explicit QAbstractItemModel(QObject *parent = Q_NULLPTR);
    virtual ~QAbstractItemModel();

    Q_INVOKABLE bool hasIndex(int row, int column, const QModelIndex &parent = QModelIndex()) const;
    Q_INVOKABLE virtual QModelIndex index(int row, int column,

[Trayon]

Correct

(more than 8 chars)

[mrjj]

@Trayon said in Help creating a tree that traverses the map of a graph:

#include <QModelIndex>

And you get error by simply including this in a default GUI project ?

[Trayon]

Yes, that is correct.

[mrjj]

@Trayon
Your Qt installation must be broken then as in a default project
there cant be any circular dependency.

invalid use of incomplete type ‘class QAbstractItemModel’

That error went away ? and now its just
"explicit QAbstractItemModel(QObject parent = Q_NULLPTR);"
error: expected ‘)’ before that is left?

In a clean project, only thing that can be wrong is the Qt files then.
Did you use Refactor and replace or anything that might have altered the Qt files ?

And just to be 100% clear,
you made a new default project with File->New and
adding #include <QModelIndex>
to that , gives error ?
If yes, then reinstall Qt.

[Trayon]

Reinstalled QT. Thanks for that tip. It got rid of those errors, but now I'm getting something a bit odd.

The error I got was:
no matching function for call to ‘QVector<TreeMap>::indexOf(const TreeMap)’*

Here:

int TreeMap::nodeIndex() const
{
    if (parent)
        return parent->nodes.indexOf(this);

    return 0;
}

Here's TreeMap.h for reference:

#ifndef TREEMAP_H
#define TREEMAP_H
#include <QString>
#include <QVector>

class TreeMap
{
public:
    TreeMap(QString name, TreeMap *parentNode = 0);
    ~TreeMap();

    TreeMap nodeAt(int position) const;
    int nodeCount() const;
    QString data() const;
    bool insertNode(int position);
    TreeMap* getParent();
    bool removeNode(int position);
    int nodeIndex() const;
    bool setData(const QString &value);

private:
    QString nodeName;
    QVector<TreeMap> nodes;
    TreeMap *parent;
};

#endif // TREEMAP_H

[SGaist]

Hi,

You have a QVector of TreeMap object, this is a pointer to the current object.

[mrjj]

Hi

nodes.indexOf(this);

"This" is a const TreeMap *
but it wants a &
int indexOf(const T &t, int from = 0) const;

so you can do

int TreeMap::nodeIndex() const {
nodes.indexOf(*this);
}

However, QVector wants an assignable data type so you will need some extra functions
http://doc.qt.io/qt-5/containers.html#assignable-data-type

something like (stripped down)

class TreeMap {
public:
  TreeMap(QString name, TreeMap* parentNode = 0) {}
  int nodeIndex() const;
  TreeMap(const TreeMap& other) {/* IMPLEMENT*/}
  TreeMap& operator=(const TreeMap& other) {/* IMPLEMENT*/}
  bool operator==(const TreeMap& other) {/* IMPLEMENT*/} // most likely wants this too
private:
  QVector<TreeMap> nodes;
};

[Trayon]

Thanks mrjj.

A few more things to add. You most likely know I'm following the example here:
http://doc.qt.io/qt-5/qtwidgets-itemviews-editabletreemodel-example.html

Why is it that the example doesn't implement these functions? QList has the same shortcoming as QVector when I tried changing it. Also, should I start a new thread with the new errors that pop up in my program, or should I continue posting here as they come?

[SGaist]

That example is using a QList of pointer to TreeItem you are using a QVector of TreeMap object.

[mrjj]

@Trayon
Hi
The main difference with the sample is that it uses pointers.
QList<TreeItem*>
So it can just compare pointers. ( they are assignable-data-type by nature)

You are use a class directly so it need you to tell it how to compare etc.
since it cannot know what members inside that should be used.

like if we have
class Car {
QString Model;
}

if we have
Car *A = new Car;
and
Car *B = new Car;
we can say if ( A == B ) and it compiler can just check is the memory address is the same.
But if we do
Car A;
Car B;
and say if ( A == B )
then what should it compare.
we can then "explain it" to the compiler with
if ( A.model == B.model )
and that is what we do with
operator==(..)

@SGaist (hehe ninjaed)

[Trayon]

Yes, but as I said, I tried changing it to QList, and it had the same shortcomings. Down the error line, I even saw the "no match for '=='" error for QList as well.