Golang TreeView example not working

[razm]

Hello there,

I am new to Qt and I try to integrate a TableView in my application. The example from github gave me a compilation error, however I managed to solve the issue by creating a constructor for my TableModel. The number of elements displayed is good but the cells are empty.

On stackoverflow I found some solutions including changing the parent of the TableModel and implementing insertRows and DeleteRows(I have different names for that but it should be ok according to the documentation since I use BeginRemoveRows and EndRemoveRows).

Can anyone tell me what is wrong with my code?

//source: https://github.com/therecipe/examples/blob/master/advanced/widgets/tableview

package main

import (
	"github.com/therecipe/qt/core"
	"github.com/therecipe/qt/widgets"
	"os"
)

type TableItem struct {
	firstName string
	lastName  string
}

type CustomTableModel struct {
	core.QAbstractItemModel


	//_ func() `constructor:"init"`
	//
	//_ func()                                  `signal:"remove,auto"`
	//_ func(item TableItem)                    `signal:"add,auto"`
	//_ func(firstName string, lastName string) `signal:"edit,auto"`

	modelData []TableItem
}

func NewCustomTableModel(parent core.QObject_ITF) *CustomTableModel {
	m := &CustomTableModel{
		QAbstractItemModel: *core.NewQAbstractItemModel(parent),
		modelData:          []TableItem{},
	}
	m.add(TableItem{"john", "doe"})
	m.add(TableItem{"john", "bob"})

	m.ConnectHeaderData(m.headerData)
	m.ConnectRowCount(m.rowCount)
	m.ConnectColumnCount(m.columnCount)
	m.ConnectData(m.data)
	//m.ConnectIn

	return m
}

func (m *CustomTableModel) headerData(section int, orientation core.Qt__Orientation, role int) *core.QVariant {
	if role != int(core.Qt__DisplayRole) || orientation == core.Qt__Vertical {
		return m.HeaderDataDefault(section, orientation, role)
	}

	switch section {
	case 0:
		return core.NewQVariant12("FirstName")
	case 1:
		return core.NewQVariant12("LastName")
	}
	return core.NewQVariant()
}

func (m *CustomTableModel) rowCount(*core.QModelIndex) int {
	return len(m.modelData)
}

func (m *CustomTableModel) columnCount(*core.QModelIndex) int {
	return 2
}

func (m *CustomTableModel) data(index *core.QModelIndex, role int) *core.QVariant {
	println(role)
	println("data")
	if role != int(core.Qt__DisplayRole) {
		return core.NewQVariant()
	}

	item := m.modelData[index.Row()]
	switch index.Column() {
	case 0:
		return core.NewQVariant12(item.firstName)
	case 1:
		return core.NewQVariant12(item.lastName)
	}
	return core.NewQVariant()
}

func (m *CustomTableModel) remove() {
	if len(m.modelData) == 0 {
		return
	}
	m.BeginRemoveRows(core.NewQModelIndex(), len(m.modelData)-1, len(m.modelData)-1)
	m.modelData = m.modelData[:len(m.modelData)-1]
	m.EndRemoveRows()
}

func (m *CustomTableModel) add(item TableItem) {
	println("add")

	m.BeginInsertRows(core.NewQModelIndex(), len(m.modelData), len(m.modelData))
	m.modelData = append(m.modelData, item)
	m.EndInsertRows()
	println(len(m.modelData))
	for e := range m.modelData {
		println(m.modelData[e].lastName,m.modelData[e].firstName )
	}
}

func (m *CustomTableModel) edit(firstName string, lastName string) {
	println("edit")
	if len(m.modelData) == 0 {
		return
	}
	m.modelData[len(m.modelData)-1] = TableItem{firstName, lastName}
	m.DataChanged(m.Index(len(m.modelData)-1, 0, core.NewQModelIndex()), m.Index(len(m.modelData)-1, 1, core.NewQModelIndex()), []int{int(core.Qt__DisplayRole)})
}

func newTableView() *widgets.QWidget {

	widget := widgets.NewQWidget(nil, 0)
	widget.SetLayout(widgets.NewQVBoxLayout())

	tableview := widgets.NewQTableView(nil)
	model := NewCustomTableModel(nil)

	tableview.SetModel(model)
	widget.Layout().AddWidget(tableview)

	remove := widgets.NewQPushButton2("remove last item", nil)
	remove.ConnectClicked(func(bool) {
		model.remove()
	})
	widget.Layout().AddWidget(remove)

	add := widgets.NewQPushButton2("add new item", nil)
	add.ConnectClicked(func(bool) {
		model.add(TableItem{"john", "doe"})
	})
	widget.Layout().AddWidget(add)

	edit := widgets.NewQPushButton2("edit last item", nil)
	edit.ConnectClicked(func(bool) {
		model.edit("bob", "omb")
	})
	widget.Layout().AddWidget(edit)

	return widget
}

func main() {
	app := widgets.NewQApplication(len(os.Args), os.Args)

	widget := newTableView()
	widget.SetWindowTitle("Tree view")
	widget.Show()

	app.Exec()
}

[mrjj]

Hi and welcome to the forums
I dont know Golang but the interface is the same so i would
check in func (m *CustomTableModel) data
that this test
if role != int(core.Qt__DisplayRole) {
return core.NewQVariant()
}

is not always returning an empty variant for each call.

also
case 0:
return core.NewQVariant12(item.firstName)
case 1:
return core.NewQVariant12(item.lastName)

does return a valid QVariant ?

i wondered why the empty one is
NewQVariant()
but with data its NewQVariant12 ?