Qtableview add item and reload table

[GeneCode]

I use QStandardItemModel to display data in QTableVIew.
i set already tableview model to the itemmodel

table->setModel(yourMomModel);

table->setModel(yourMomModel);

To copy to clipboard, switch view to plain text mode 

then i added the item in model

yourMomModel.append(item2);

yourMomModel.append(item2);

To copy to clipboard, switch view to plain text mode 

but the data not showing in QtableView.
anybody know whats wrong thanks.

[Santosh Reddy]

How did you create the model and item?

[d_stranz]

These two lines of code are incompatible:

table->setModel(yourMomModel);
 
// and
 
yourMomModel.append(item2);

table->setModel(yourMomModel);

// and

yourMomModel.append(item2);

To copy to clipboard, switch view to plain text mode 

In the first line QAbstractItemView::setModel() takes a pointer to a model. In the second line, you use "dot" notation to dereference, which implies "yourMomModel" is a stack or member variable, not a pointer. Which is it? Do they refer to the same instance?

[GeneCode]

nvm. i solved it.

[GeneCode]

Here's how i did it:

I used QstandardItemModel and add QStandardItem to it.
then apply the model to my QTableView.

code:

// header
private:
 QStandardItemModel *myModel

// header
private:
 QStandardItemModel *myModel

To copy to clipboard, switch view to plain text mode 

// cpp
// in constructor
myModel =  new QStandardItemModel(0, 0, this); // an empty model
 
ui->myTableView->setModel(myModel);
 
// create the item
 QStandardItem *item1 = new QStandardItem("Test");
 
// set the item to the model
myModel->setItem(0,0,item1); // 0,0 is row/colum.

// cpp
// in constructor
myModel =  new QStandardItemModel(0, 0, this); // an empty model

ui->myTableView->setModel(myModel);

// create the item
 QStandardItem *item1 = new QStandardItem("Test");

// set the item to the model
myModel->setItem(0,0,item1); // 0,0 is row/colum.

To copy to clipboard, switch view to plain text mode 

[d_stranz]

Ah, this is a common misunderstanding. You have created an empty model (0 rows and 0 columns). Calling setItem( row, column, item ) requires that the row and column already exist. That is not the case for an empty model, so nothing happens.

You should take one of the following steps:

1 - create your model with non-zero row and column counts
2 - use setRowCount() and setColumnCount() to grow the model as needed
3 - use appendRow() or appendColumn() to add items and grow the model at the same time

A typical scenario is to create a model with 0 rows and "n" columns (since you usually know how many columns your table will have). Then you create the list of new items for a row and call appendRow() with the list. That sticks the row onto the end of the model and grows rowCount() by 1.

[GeneCode]

Ah, this is a common misunderstanding. You have created an empty model (0 rows and 0 columns). Calling setItem( row, column, item ) requires that the row and column already exist. That is not the case for an empty model, so nothing happens.

You should take one of the following steps:

1 - create your model with non-zero row and column counts
2 - use setRowCount() and setColumnCount() to grow the model as needed
3 - use appendRow() or appendColumn() to add items and grow the model at the same time

A typical scenario is to create a model with 0 rows and "n" columns (since you usually know how many columns your table will have). Then you create the list of new items for a row and call appendRow() with the list. That sticks the row onto the end of the model and grows rowCount() by 1.

Actually what I need was the tableview start as empty. And then I setitem starting from 0,0. Seems to add items to it nicely.

[d_stranz]

void QStandardItemModel::setItem(int row, int column, QStandardItem *item)

Sets the item for the given row and column to item. The model takes ownership of the item. If necessary, the row count and column count are increased to fit the item.

You are correct, my mistake. I rarely use QStandardItemModel, which behaves differently in this regard. Other types of models typically require the code to set the size of the model before adding to it.