小编Zha*_*gQI的帖子

create ROLE testROLE with PASSWORD = 'test';
create ROLE testROLE with PASSWORD = 'test';

list ROLES 成功显示角色.

DROP ROLE testROLE;
InvalidRequest: code=2200 [Invalid query] message="testrole doesn't exist"
DROP ROLE test1;
InvalidRequest: code=2200 [Invalid query] message="test1 doesn't exist"

CQLSH输出的图像.

该角色显示在列表中但无法删除.怎么会发生这种情况？

queue < int* > qq;

for (int i = 0; i < N; i++) {
    int cc[2] = {i, i + 1};
    qq.push(cc);
}

N很大但不是Exact所以我想要使用队列.我想将许多数组存储到队列中,但qq存储的数组是相同的.我该怎么做？

我可以找到一些如何使用标准模型和标准视图的示例。

http://doc.qt.io/qt-5/modelview.html

http://doc.qt.io/qt-5/qtwidgets-itemviews-simplewidgetmapper-example.html

但我就是找不到一个如何使用QAbstractModelmake my ownmodel并自行使用它的示例view/widget。

更新模型后，支架视图将更新，但我自己的视图不会更新。

完整代码：

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from  PyQt5.QtWidgets import (QWidget, QLabel, QDataWidgetMapper,
                              QLineEdit, QApplication, QGridLayout)
from PyQt5.QtCore import QAbstractListModel, Qt
from PyQt5.QtWidgets import QListView


class Window(QWidget):
    def __init__(self, model, parent=None):
        super(Window, self).__init__(parent)

        self.model = model

        # Set up the widgets.
        nameLabel = QLabel("Na&me:")
        nameEdit = QLineEdit()

        # Set up the mapper.
        self.mapper = QDataWidgetMapper(self)
        self.mapper.setModel(self.model)
        self.mapper.addMapping(nameEdit, 0)

        layout = QGridLayout()
        layout.addWidget(nameLabel, 0, 0, 1, 1) …