Property editor

sitesv

Hi!
Trying to do something like qt creator property editor.
As I know, there are few variants:

QTreeWidget + setItemWidget
QTreeView + setItemDelegate
QTreeView + setIndexWidget
What is the best way?

mrjj

Hi
The best way is 2 as delegates are much lighter than setItemWidget.
But if only a few rows are needed then all of them will work.

That said, you could also be inspired by others
https://github.com/abhijitkundu/QtPropertyBrowser

sitesv

Trying to understand how to use Qt::UserRole...

const int MyTypeRole = Qt::UserRole + 1;

enum DelegateType{
    DT_Text,
    DT_Checkbox,
    DT_Combo
}

Where I have to insert the string like this? :

item->setData(DT_Checkbox, MyTypeRole);

I using QAbstractItemModel and QTreeView

SGaist

Hi,

As silly as may sound: when appropriate.

When you create the item for example or when you know what to put in that item.

sitesv

@SGaist said in Property editor:

Hi,

As silly as may sound: when appropriate.

When you create the item for example or when you know what to put in that item.

I have the next incomprehension:
I fill in a TreeItems structure and after that I execute

emit dataChanged(QModelIndex(), QModelIndex());

...for updating view.

As I understand right, after dataChange(...) execution there is automatic start execution of model functions data(...), flags(...), headerData(..) for connection data with the model.

I tryed to insert index.model()->setData(...) for UserRole into data(...) function, where a node text returns for DisplayRole...
But there is no access to setData...

sitesv

This post is deleted!

sitesv

Some ideas?

SGaist

Please show some patience and allow at least 24 hours before bumping your own thread. This is a voluntary driven forum and not all people are living in the same time zone.

That said, why are you calling setData in your data function ?

Can you explain when do you use these additional roles ?

sitesv

@SGaist said in Property editor:

Please show some patience and allow at least 24 hours before bumping your own thread. This is a voluntary driven forum and not all people are living in the same time zone.

That said, why are you calling setData in your data function ?

Can you explain when do you use these additional roles ?

Hi!
Thank you for the explanation.
I trying to create something like a simple property editor with QTreeView + QAbstractItemModel + QItemDelegate.
The example, that was introduced by @mrjj is complicated for me.
I have a data structure.
I need to create a QComboBox, QCheckBox, or QLineEditor delegate for one column of QTreeView depending on the data's item type.
I really don't understand how to register new role for my createEditor method of my delegate.

SGaist

How do you determine the data's type ?

sitesv

@SGaist said in Property editor:

How do you determine the data's type ?

By "type" variable from my data structure.
1 - QLineEditor
2 - QCheckBox
3 - QComboBox

nagesh

@sitesv I hope, you are experimenting somewhat similar to the example "SpinBoxDelegate".

Populate the model data using setdata function, provide data for edit role and user role also.

model.setData(index, DT_Checkbox, Qt::UserRole);

In your case

I need to create a QComboBox, QCheckBox, or QLineEditor delegate for one column of QTreeView depending on the data's item type.

In example SpinBoxDelegate function

QWidget *SpinBoxDelegate::createEditor

creates delegate widget QSpinBox.

Similar to that based on "QModelIndex index" retrive the type of data and create the delegate widget.
eg:
int type = index.model()->data(index, Qt::UserRole).toInt();

now based on the type create and return the widget Checkbox, combo etc.

follow the similar approach in setEditorData, setModelData function.

sitesv

@nagesh said in Property editor:

@sitesv I hope, you are experimenting somewhat similar to the example "SpinBoxDelegate".

Populate the model data using setdata function, provide data for edit role and user role also.
model.setData(index, DT_Checkbox, Qt::UserRole);
In your case
I need to create a QComboBox, QCheckBox, or QLineEditor delegate for one column of QTreeView depending on the data's item type.
In example SpinBoxDelegate function
QWidget *SpinBoxDelegate::createEditor
creates delegate widget QSpinBox.

Similar to that based on "QModelIndex index" retrive the type of data and create the delegate widget.
eg:
int type = index.model()->data(index, Qt::UserRole).toInt();

now based on the type create and return the widget Checkbox, combo etc.

follow the similar approach in setEditorData, setModelData function.

Thank you!
But I don't understand how to create an 'index' while populating the model via the setData function...
Could you please explain this?

I have been trying to do something like this:

QModelIndex idx = model->index(0,0,QModelIndex());
setData(idx, "test1", Qt::DisplayRole);
setData(idx, 111, Qt::UserRole);

but idx.isValid() returns 'false'

UPD:
First of all, I should create tree-style data structure of TreeItems.
For each TreeItem, I need to calculate the index and use setData.
Is I understand right?

int TreeModel::rowCount(const QModelIndex &parent) const
{
    TreeItem *parentItem;

    if (!parent.isValid())
        parentItem = rootItem;
    else
        parentItem = static_cast<TreeItem*>(parent.internalPointer());

    return parentItem->childCount();
}

int TreeModel::columnCount(const QModelIndex &parent) const
{
    if (parent.isValid())
        return static_cast<TreeItem*>(parent.internalPointer())->columnCount();
    return rootItem->columnCount();
}

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

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

    TreeItem *item = static_cast<TreeItem*>(index.internalPointer());
    if(role == Qt::DisplayRole){
        return item->data(index.column());
    }
    return QVariant();
}

bool TreeModel::setData(const QModelIndex &index, const QVariant &value, int role){
    if (!index.isValid())
        return false;
    if(role == Qt::DisplayRole){
        TreeItem *item = static_cast<TreeItem*>(index.internalPointer());
        bool result = item->setData(index.column(), value);
        if (result) {
            emit dataChanged(index, index);
            return true;
        }
    }
    return false;
}

nagesh

@sitesv

First of all, I should create tree-style data structure of TreeItems.
For each TreeItem, I need to calculate the index and use setData.
Is I understand right?

Absolutely right.. refer editabletreemodel example project...
In the tree model override index function

sitesv

How to make QComboBox or QCheckBox delegates show constantly?
They appear when I clicking on the cell only.
Or this approach (QTreeView + custom delegates) is not suitable for my case?