How to see if a value already exists in the model for treeview?

QtisHard

I have made a model for a treeview.

I want to see if an item already exists in the model before I append it into the treeview.
How do I do that?

instead of having so many 200s, I want only 1 200 in which all the other values are present.

Please do guide me

Christian Ehrlicher

Look into the model and see if the data you want to add is already there.

QtisHard

How do I do that?

Christian Ehrlicher

@QtisHard said in How to see if a value already exists in the model for treeview?:

How do I do that?

Since I don't know how you created the model I don't know exactly but iterating through the data of the model shouldn't be that hard.

QtisHard

https://www.qtcentre.org/threads/44877-Convert-XML-to-QTreeView

This is what I used to create my model

Apologies for the continuous questions but I am still in the learning phase so its not that easy for me
please do guide me to some resources so ik how to proceed

Christian Ehrlicher

Since you're using a QStandardItemModel I would suggest to open the documentation for this class and see if you can find a function which looks like you can search for data inside the model. Reading the documentation seems to be really hard.

QtisHard

I did look into this but I was not able to find anything as such

void Dialog::preOrder(QDomNode dom, QStandardItemModel *model){
if(dom.isNull())
{
return;
}
QString aux = dom.nodeName().toStdString().c_str();
QString qsGroupID = "GroupID";
QString qsName = "Name";
if(dom.isText()){
aux = dom.parentNode().nodeName().toStdString().c_str();
if(strcmp(aux.toStdString().c_str(),qsGroupID.toStdString().c_str())==0){

    insertFather(dom.nodeValue());
    setItemParam(model);
    }
    if(strcmp(aux.toStdString().c_str(),qsName.toStdString().c_str())==0){
       insertChildren(dom.nodeValue());
      }
    }else{
      preOrder(dom.firstChild(), model);
      preOrder(dom.nextSibling(), model);
  }

}

This is the code I have to insert the items into the model view. What should i change so that all the values dont come and they come as a common parent

JonB

@QtisHard said in How to see if a value already exists in the model for treeview?:

I want to see if an item already exists in the model before I append it into the treeview.

I did look into this but I was not able to find anything as such

What about QList<QStandardItem *> QStandardItemModel::findItems(const QString &text, Qt::MatchFlags flags = Qt::MatchExactly, int column = 0) const ?

JonB

@QtisHard
On a completely separate note, what about getting rid of all these unnecessary and ugly .toStdString().c_str()? And we don't use strcmp() any longer these days.

QString aux = dom.nodeName().toStdString().c_str();

dom.nodeName() returns a QString. You then convert that to a std::string, get the C string out of that and assign it to QString aux, which requires converting a C string all the way back to a QString! QString aux = dom.nodeName() is all you need.

if (strcmp(aux.toStdString().c_str(),qsGroupID.toStdString().c_str())==0)

Why not

if (aux == qsGroupID)

?! Isn't that shorter, clearer and easier (plus more efficient)? :)

Christian Ehrlicher

@QtisHard said in How to see if a value already exists in the model for treeview?:

I did look into this but I was not able to find anything as such

Then you should look again... searching for 'find' would be a good start.