Виджеты в pyqt5

Содержание:

Changes to Qt Widgets

() and () signatures are changed to take arguments of type instead of .
is removed as related getter and setter functions in QWidget and QApplication are removed. Input contexts are now platform-specific.
() is deprecated. Use () instead.
The classes are removed, and their members are merged with the respective base classes. The removed classes are left as typedefs for binary compatibility.
QGraphicsItem and its derived classes can no longer pass a QGraphicsScene to the item’s constructor. Construct the item without a scene and call () to add the item to the scene.
is removed. Use QAbstractProxyModel and the related classes instead. A copy of is available in the Ui Helpers repository.

Changes to QApplication

is removed, because the introduction of QPA made it redundant.
and virtual methods that were used for session management are removed. Connect to the and signals instead. Use () if the if your window needs to know whether it is being called during shutdown.

Changes to QStyle

and are removed, and the () and () functions are made pure virtual now. The removed functions were introduced in Qt 4 for binary compatibility reasons.
, , , and are replaced with a new fusion style. If your application depends on any of these removed styles, you can either use the qtstyleplugins project to get these styles or update your application to use the new fusion style. For more details about this change, see https://blog.qt.io/blog/2012/10/30/cleaning-up-styles-in-qt5-and-adding-fusion/.
The following QStyle implementations have been made internal:
- QFusionStyle
- QGtkStyle
- QMacStyle
- QWindowsCEStyle
- QWindowsMobileStyle
- QWindowsStyle
- QWindowsVistaStyle
- QWindowsXPStyle
Instead of creating instances or inheriting these classes directly, use:
- QStyleFactory for creating instances of specific styles.
- QProxyStyle for customizing existing style implementations.
- QCommonStyle as a base for implementing full custom styles.

Changes to QHeaderView

The following functions are deprecated:

— Use () instead.
— Use () instead.
— Use () instead.
— Use () instead.
— Use () instead.
— Use () instead.

Changes to QAbstractItemView

The derived classes now emit the signal on the left mouse click only, instead of all mouse clicks.
The virtual () function signature now includes the roles that have changed. The signature is consistent with the signal in the model.

Класс QVBoxLayout

Класс QVBoxLayout предназначен для создания вертикального ряда из выравниваемых объектов. Добавление виджетов в компоновку осуществляется с помощью метода addWidget().

Заголовочный файл — verticalbox.h:

#pragma once

#include <QWidget>

class VerticalBox : public QWidget {

public:
VerticalBox(QWidget *parent = 0);
};

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#pragma once

#include <QWidget>

classVerticalBoxpublicQWidget{

public

VerticalBox(QWidget*parent=);

};

В нашем примере у нас есть один менеджер вертикальный компоновки, в который мы устанавливаем пять кнопок. При этом параметры кнопок задаются так, чтобы они имели возможность расширяться в обоих направлениях.

Файл с реализацией — verticalbox.cpp:

#include «verticalbox.h»
#include <QVBoxLayout>
#include <QPushButton>

VerticalBox::VerticalBox(QWidget *parent)
: QWidget(parent) {

QVBoxLayout *vbox = new QVBoxLayout(this);
vbox->setSpacing(1);

QPushButton *settings = new QPushButton(«Settings», this);
settings->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

QPushButton *accounts = new QPushButton(«Accounts», this);
accounts->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

QPushButton *loans = new QPushButton(«Loans», this);
loans->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

QPushButton *cash = new QPushButton(«Cash», this);
cash->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

QPushButton *debts = new QPushButton(«Debts», this);
debts->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

vbox->addWidget(settings);
vbox->addWidget(accounts);
vbox->addWidget(loans);
vbox->addWidget(cash);
vbox->addWidget(debts);

setLayout(vbox);
}

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#include «verticalbox.h»
#include <QVBoxLayout>
#include <QPushButton>

VerticalBox::VerticalBox(QWidget*parent)

QWidget(parent){

QVBoxLayout*vbox=newQVBoxLayout(this);

vbox->setSpacing(1);

QPushButton*settings=newQPushButton(«Settings»,this);

settings->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

QPushButton*accounts=newQPushButton(«Accounts»,this);

accounts->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

QPushButton*loans=newQPushButton(«Loans»,this);

loans->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

QPushButton*cash=newQPushButton(«Cash»,this);

cash->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

QPushButton*debts=newQPushButton(«Debts»,this);

debts->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

vbox->addWidget(settings);

vbox->addWidget(accounts);

vbox->addWidget(loans);

vbox->addWidget(cash);

vbox->addWidget(debts);

setLayout(vbox);

}

Создаём объект класса и устанавливаем интервал между дочерними виджетами в 1 пиксель:

QVBoxLayout *vbox = new QVBoxLayout(this);
vbox->setSpacing(1);

1 2	QVBoxLayout*vbox=newQVBoxLayout(this); vbox->setSpacing(1);

Теперь мы создаём кнопку и устанавливаем для неё политику размера . Дочерние виджеты управляются менеджером компоновки. По умолчанию кнопка растягивается по горизонтали и имеет фиксированный размер по вертикали. Если мы хотим изменить его, мы должны и для вертикали установить новую политику размера (). Как видите, в нашем случае кнопка будет расширяться в обоих направлениях:

QPushButton *settings = new QPushButton(«Settings», this);
settings->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

1 2	QPushButton*settings=newQPushButton(«Settings»,this); settings->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

Добавляем дочерние виджеты в менеджер компоновки при помощи метода addWidget():

vbox->addWidget(settings);
vbox->addWidget(accounts);
…

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vbox->addWidget(settings);

vbox->addWidget(accounts);

…

Сообщаем нашей программе использовать в качестве менеджера компоновки:

setLayout(vbox);

1	setLayout(vbox);

Главный файл приложения — main.cpp:

#include «verticalbox.h»
#include <QApplication>

int main(int argc, char *argv[]) {

QApplication app(argc, argv);

VerticalBox window;

window.resize(240, 230);
window.setWindowTitle(«VerticalBox»);
window.show();

return app.exec();
}

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#include «verticalbox.h»
#include <QApplication>

intmain(intargc,char*argv){

QApplication app(argc,argv);

VerticalBox window;

window.resize(240,230);

window.setWindowTitle(«VerticalBox»);

window.show();

returnapp.exec();

}

Результат:

Detailed Description

Table items are used to hold pieces of information for table widgets. Items usually contain text, icons, or checkboxes

The QTableWidgetItem class is a convenience class that replaces the class in Qt 3. It provides an item for use with the QTableWidget class.

Top-level items are constructed without a parent then inserted at the position specified by a pair of row and column numbers:

     *newItem = new (tr("%1").arg(
        pow(row, column+1)));
    tableWidget->setItem(row, column, newItem);

Each item can have its own background brush which is set with the () function. The current background brush can be found with (). The text label for each item can be rendered with its own font and brush. These are specified with the () and () functions, and read with () and ().

By default, items are enabled, editable, selectable, checkable, and can be used both as the source of a drag and drop operation and as a drop target. Each item’s flags can be changed by calling () with the appropriate value (see ). Checkable items can be checked and unchecked with the () function. The corresponding () function indicates whether the item is currently checked.

Member Function Documentation

void QValueAxis::applyNiceNumbers()

Modifies the current range and number of tick marks on the axis to look nice. The algorithm considers numbers that can be expressed as a form of 1*10^n, 2* 10^n, or 5*10^n to be nice numbers. These numbers are used for setting spacing for the tick marks.

See also () and ().

This signal is emitted when the format of axis labels changes.