def flags(self, index):
        """Return the item flags for index.

        Override QAbstractItemModel::flags.

        Return: The item flags, or Qt.NoItemFlags on error.
        """
        if not index.isValid():
            return Qt.NoItemFlags
        if index.parent().isValid():
            # item
            return (Qt.ItemIsEnabled | Qt.ItemIsSelectable |
                    Qt.ItemNeverHasChildren)
        else:
            # category
            return Qt.NoItemFlags 

def display_utxos(self):
        def item(value):
            item = QTableWidgetItem(value)
            item.setTextAlignment(Qt.AlignCenter)
            item.setFlags(Qt.ItemIsEnabled | Qt.ItemIsSelectable)
            return item

        self.tableW.setRowCount(len(self.utxos))
        for row, utxo in enumerate(self.utxos):
            pivxAmount = round(int(utxo.get('satoshis', 0))/1e8, 8)
            self.tableW.setItem(row, 0, item(str(pivxAmount)))
            self.tableW.setItem(row, 1, item(str(utxo['confirmations'])))
            self.tableW.setItem(row, 2, item(utxo.get('txid', None)))
            self.tableW.setItem(row, 3, item(str(utxo.get('vout', None))))

        if len(self.utxos):
            self.tableW.resizeColumnsToContents()
            self.lblMessage.setVisible(False)
            self.tableW.horizontalHeader().setSectionResizeMode(2, QHeaderView.Stretch)

        else:
            self.lblMessage.setText('<b style="color:purple">No UTXO found for current address.\nEnter tx manually</b>')
            self.lblMessage.setVisible(True) 

def _update_tree(self, conf, value):
        """Update the block tree"""
        self._block_tree.clear()
        for block in self._helper.cf.log.log_blocks:
            item = QtWidgets.QTreeWidgetItem()
            item.setFlags(Qt.ItemIsEnabled |
                          Qt.ItemIsSelectable)
            item.setData(0, Qt.DisplayRole, block.id)
            item.setData(1, Qt.EditRole, block.name)
            item.setData(2, Qt.DisplayRole, (block.period_in_ms))
            item.setData(3, Qt.DisplayRole, block.added)
            item.setData(4, Qt.EditRole, block.started)
            item.setData(5, Qt.EditRole, block.err_no)
            for var in block.variables:
                subItem = QtWidgets.QTreeWidgetItem()
                subItem.setFlags(Qt.ItemIsEnabled |
                                 Qt.ItemIsSelectable)
                subItem.setData(6, Qt.EditRole, var.name)
                item.addChild(subItem)

            self._block_tree.addTopLevelItem(item)
            self._block_tree.expandItem(item) 

def fill_tableWidget(self):
        ''' Fill table widget with data. '''

        numRows = self.ui.tableWidget.rowCount()
        for row in range(0, numRows):
            self.ui.tableWidget.removeRow(0)
        self.ui.tableWidget.setColumnCount(len(self.fields))
        for c, field in enumerate(self.fields):
            item = QtWidgets.QTableWidgetItem(field + "\n" + self.fields_type[c] + "\n")
            self.ui.tableWidget.setHorizontalHeaderItem(c, item)
        self.ui.tableWidget.setRowCount(len(self.data))
        for row in range(0, len(self.data)):
            for col in range(0, len(self.fields)):
                value = str(self.data[row][col])
                item = QtWidgets.QTableWidgetItem(value)
                item.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)  # not editatble
                self.ui.tableWidget.setItem(row, col, item)
        self.ui.tableWidget.resizeColumnsToContents()
        for col in range(0, self.ui.tableWidget.columnCount()):
            if self.ui.tableWidget.columnWidth(col) > 200:
                self.ui.tableWidget.setColumnWidth(col, 200) 

def __init__(self, segment, scaler, text_for_segment, code_av_dialog):
            super(SegmentGraphicsItem, self).__init__(None)

            self.segment = segment
            self.scaler = scaler
            #self.text_for_segment = text_for_segment
            self.code_av_dialog = code_av_dialog
            self.reload_segment = False
            self.setFlag(self.ItemIsSelectable, True)
            tooltip = self.segment['codename'] + " "
            seg_time = "[" + msecs_to_mins_and_secs(self.segment['pos0']) + " - "
            seg_time += msecs_to_mins_and_secs(self.segment['pos1']) + "]"
            tooltip += seg_time
            if self.segment['memo'] != "":
                tooltip += "\n" + _("Memo: ") + self.segment['memo']
            self.setToolTip(tooltip)
            self.draw_segment() 

def flags(self, index):
        if not index.isValid():
            return 0

        if index.column() == 0:
            return Qt.ItemIsEnabled | Qt.ItemIsSelectable

        return Qt.ItemIsEditable | Qt.ItemIsEnabled | Qt.ItemIsSelectable 

def flags(self, index):
        flags = QAbstractTableModel.flags(self, index)
        if not index.isValid():
            return flags
        prop = self.getProperty(index)
        if prop is None:
            return flags
        flags |= Qt.ItemIsEnabled
        flags |= Qt.ItemIsSelectable
        mode = prop.get('mode', "Read/Write")
        if "Write" in mode:
            flags |= Qt.ItemIsEditable
        return flags 

def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable 

def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable 

def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable 

def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable 

def __InitFieldItem(self, parent, item):
        treeItem = QTreeWidgetItem(parent)
        treeItem.setText(0, item)
        treeItem.setFlags(Qt.ItemIsUserCheckable | Qt.ItemIsEnabled | Qt.ItemIsSelectable)
        treeItem.setCheckState(0, Qt.Unchecked)

        return treeItem 

def initCategories(self):
        generalButton = QListWidgetItem(self.categories)
        generalButton.setIcon(QIcon(':/images/settings-general.png'))
        generalButton.setText('General')
        generalButton.setToolTip('General settings')
        generalButton.setTextAlignment(Qt.AlignHCenter)
        generalButton.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)
        videoButton = QListWidgetItem(self.categories)
        videoButton.setIcon(QIcon(':/images/settings-video.png'))
        videoButton.setText('Video')
        videoButton.setToolTip('Video settings')
        videoButton.setTextAlignment(Qt.AlignHCenter)
        videoButton.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)
        themeButton = QListWidgetItem(self.categories)
        themeButton.setIcon(QIcon(':/images/settings-theme.png'))
        themeButton.setText('Theme')
        themeButton.setToolTip('Theme settings')
        themeButton.setTextAlignment(Qt.AlignHCenter)
        themeButton.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)
        ffmpegButton = QListWidgetItem(self.categories)
        ffmpegButton.setIcon(QIcon(':/images/settings-ffmpeg.png'))
        ffmpegButton.setText('Tools')
        ffmpegButton.setToolTip('Tools settings')
        ffmpegButton.setTextAlignment(Qt.AlignHCenter)
        ffmpegButton.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)
        logsButton = QListWidgetItem(self.categories)
        logsButton.setIcon(QIcon(':/images/settings-logs.png'))
        logsButton.setText('Logs')
        logsButton.setToolTip('Logging settings')
        logsButton.setTextAlignment(Qt.AlignHCenter)
        logsButton.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)
        self.categories.currentItemChanged.connect(self.changePage)
        self.categories.setCurrentRow(0)
        self.categories.setMaximumWidth(self.categories.sizeHintForColumn(0) + 2) 

def renderClips(self, cliptimes: list) -> int:
        self.clear()
        externalCount = 0
        for index, clip in enumerate(cliptimes):
            chapterName, endItem = '', ''
            if isinstance(clip[1], QTime):
                endItem = clip[1].toString(self.parent.timeformat)
                self.parent.totalRuntime += clip[0].msecsTo(clip[1])
            listitem = QListWidgetItem(self)
            listitem.setToolTip('Drag to reorder clips')
            if len(clip[3]):
                listitem.setToolTip(clip[3])
                externalCount += 1
            if self.parent.createChapters:
                chapterName = clip[4] if clip[4] is not None else 'Chapter {}'.format(index + 1)
            listitem.setStatusTip('Reorder clips with mouse drag & drop or right-click menu on the clip to be moved')
            listitem.setTextAlignment(Qt.AlignVCenter)
            listitem.setData(Qt.DecorationRole + 1, clip[2])
            listitem.setData(Qt.DisplayRole + 1, clip[0].toString(self.parent.timeformat))
            listitem.setData(Qt.UserRole + 1, endItem)
            listitem.setData(Qt.UserRole + 2, clip[3])
            listitem.setData(Qt.UserRole + 3, chapterName)
            listitem.setFlags(Qt.ItemIsSelectable | Qt.ItemIsDragEnabled | Qt.ItemIsEnabled)
            self.addItem(listitem)
            if isinstance(clip[1], QTime) and not len(clip[3]):
                self.parent.seekSlider.addRegion(clip[0].msecsSinceStartOfDay(), clip[1].msecsSinceStartOfDay())
        return externalCount 

def flags(self, QModelIndex):
        return Qt.ItemIsSelectable | Qt.ItemIsEnabled 

def flags(self, QModelIndex):
        return Qt.ItemIsSelectable | Qt.ItemIsEnabled 

def flags(self, QModelIndex):
        return Qt.ItemIsEditable | Qt.ItemIsSelectable | Qt.ItemIsEnabled 

def flags(self, index):
        if not index.isValid():
            return 0
        flags = Qt.ItemIsSelectable | Qt.ItemIsEnabled | Qt.ItemIsDropEnabled
        return flags 

def flags(self, index):
        base_flag = Qt.ItemIsEnabled | Qt.ItemIsSelectable
        if self.is_editable:
            return base_flag | Qt.ItemIsEditable
        else:
            return base_flag 

def flags(self, index):
        f = Qt.ItemIsEnabled | Qt.ItemIsSelectable
        if index.column() == 0:
            f = f | Qt.ItemIsUserCheckable | Qt.ItemIsEditable
        return f 

def update(self, checked=False, labels=None, custom_labels=None):
        """Use this function when we make changes to the list of labels or when
        we load a new dataset.

        Parameters
        ----------
        checked : bool
            argument from clicked.connect
        labels : list of str
            list of labels in the dataset (default)
        custom_labels : list of str
            list of labels from a file
        """
        if labels is not None:
            self.setEnabled(True)
            self.chan_name = labels

        self.table.blockSignals(True)
        self.table.clearContents()
        self.table.setRowCount(len(self.chan_name))

        for i, label in enumerate(self.chan_name):
            old_label = QTableWidgetItem(label)
            old_label.setFlags(Qt.ItemIsSelectable | Qt.ItemIsEnabled)

            if custom_labels is not None and i < len(custom_labels) and custom_labels[i]:  # it's not empty string or None
                label_txt = custom_labels[i]
            else:
                label_txt = label
            new_label = QTableWidgetItem(label_txt)

            self.table.setItem(i, 0, old_label)
            self.table.setItem(i, 1, new_label)

        self.table.blockSignals(False) 

def flags(self, index):
        if not index.isValid():
            return None
        if index.column() == 0:
            return (
                Qt.ItemIsEnabled | Qt.ItemIsSelectable |
                Qt.ItemIsUserCheckable)
        else:
            return Qt.ItemIsEnabled | Qt.ItemIsSelectable 

def __init__(self, *args, **kwargs):
        super(Window, self).__init__(*args, **kwargs)
        self.setItemDelegateForColumn(0, NoColorItemDelegate(self))

        # 父节点（不可选中）
        pitem1 = QTreeWidgetItem(self, ['parent item 1'])
        # 设置不可选中
        pitem1.setFlags(pitem1.flags() & ~Qt.ItemIsSelectable)
        # 设置一个标识用于屏蔽鼠标事件
        pitem1.setData(0, Qt.UserRole + 1, True)

        pitem2 = QTreeWidgetItem(self, ['parent item 2'])
        pitem2.setFlags(pitem2.flags() & ~Qt.ItemIsSelectable)
        pitem2.setData(0, Qt.UserRole + 1, True)

        # 子节点（可选）
        citem1 = QTreeWidgetItem(pitem1, ['child item 1'])
        citem2 = QTreeWidgetItem(pitem2, ['child item 2'])

        self.expandAll()

        # 信号槽
        self.itemActivated.connect(self.onItemActivated)
        self.itemClicked.connect(self.onItemClicked)
        self.itemDoubleClicked.connect(self.onItemDoubleClicked)
        self.itemPressed.connect(self.onItemPressed) 

def variableTypeChanged(self, row):
        """
        variable type combobox changed
        """

        if self.twVariables.cellWidget(row, tw_indVarFields.index("type")).currentText() == SET_OF_VALUES:
            if self.twVariables.item(row, tw_indVarFields.index("possible values")).text() == "NA":
                self.twVariables.item(row, tw_indVarFields.index("possible values")).setText("Double-click to add values")
        else:
            # check if set of values defined
            if self.twVariables.item(row, tw_indVarFields.index("possible values")).text() not in ["NA", "Double-click to add values"]:
                if dialog.MessageDialog(programName, "Erase the set of values?", [YES, CANCEL]) == CANCEL:
                    self.twVariables.cellWidget(row, tw_indVarFields.index("type")).setCurrentIndex(SET_OF_VALUES_idx)
                    return
                else:
                    self.twVariables.item(row, tw_indVarFields.index("possible values")).setText("NA")
            else:
                self.twVariables.item(row, tw_indVarFields.index("possible values")).setText("NA")

            if self.twVariables.cellWidget(row, tw_indVarFields.index("type")).currentText() == TIMESTAMP:
                self.twVariables.item(row, tw_indVarFields.index("default value")).setFlags(Qt.ItemIsEnabled)
            else:
                self.twVariables.item(row, tw_indVarFields.index("default value")).setFlags(
                    Qt.ItemIsSelectable | Qt.ItemIsEditable | Qt.ItemIsEnabled)


            # check compatibility between variable type and default value
            if not self.check_variable_default_value(self.twVariables.item(row, tw_indVarFields.index("default value")).text(),
                                                     self.twVariables.cellWidget(row, tw_indVarFields.index("type")).currentIndex()):
                QMessageBox.warning(self,
                                    programName + " - Independent variables error",
                                    "The default value ({0}) of variable <b>{1}</b> is not compatible with variable type".format(
                                        self.twVariables.item(row, tw_indVarFields.index("default value")).text(),
                                        self.twVariables.item(row, tw_indVarFields.index("label")).text())) 

def flags(self, index: QModelIndex):
        if index.isValid():
            alignment_offset = self.get_alignment_offset_at(index.row())
            if index.column() < alignment_offset:
                return Qt.ItemIsSelectable | Qt.ItemIsEnabled

            if self.is_writeable:
                return Qt.ItemIsEnabled | Qt.ItemIsEditable | Qt.ItemIsSelectable
            else:
                return Qt.ItemIsEnabled | Qt.ItemIsSelectable
        else:
            return Qt.NoItemFlags 

def flags(self, index: QModelIndex):
        return Qt.ItemIsSelectable | Qt.ItemIsEnabled | Qt.ItemIsEditable 

def flags(self, index):
        flags = Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsEditable

        try:
            lbl = self.labels[index.row()]
        except IndexError:
            return flags

        if len(lbl.fuzz_values) > 1:
            flags |= Qt.ItemIsUserCheckable
        else:
            lbl.fuzz_me = False
        return flags 

def flags(self, index: QModelIndex):
        return Qt.ItemIsSelectable | Qt.ItemIsEnabled | Qt.ItemIsEditable 

def flags(self, index):
        return Qt.ItemIsEnabled | Qt.ItemIsSelectable | Qt.ItemIsUserCheckable 

def flags(self, index: QModelIndex):
        if not index.isValid():
            return Qt.ItemIsEnabled

        return Qt.ItemIsEnabled | Qt.ItemIsDropEnabled | Qt.ItemIsSelectable | Qt.ItemIsDragEnabled | Qt.ItemIsEditable