QStackedWidget 類

QStackedWidget 類提供每次僅一 Widget 可見的小部件堆棧。更多...

頭：	#include <QStackedWidget>
qmake:	QT += widgets
繼承：	QFrame

所有成員列錶，包括繼承成員

特性

count : const int
currentIndex : int

公共函數

	QStackedWidget (QWidget * parent = nullptr)
virtual	~QStackedWidget ()
int	addWidget (QWidget * widget )
int	count () const
int	currentIndex () const
QWidget *	currentWidget () const
int	indexOf (QWidget * widget ) const
int	insertWidget (int index , QWidget * widget )
void	removeWidget (QWidget * widget )
QWidget *	widget (int index ) const

公共槽

void	setCurrentIndex (int index )
void	setCurrentWidget (QWidget * widget )

信號

void	currentChanged (int index )
void	widgetRemoved (int index )

重實現保護函數

virtual bool

event (QEvent * e ) override

詳細描述

QStackedWidget 可以用於創建的用戶界麵，類似於某種提供通過 QTabWidget 。它是方便布局 Widget，構建基於 QStackedLayout 類。

像 QStackedLayout ，可以采用很多子級 Widget (頁麵) 來構建和填充 QStackedWidget：

    QWidget *firstPageWidget = new QWidget;
    QWidget *secondPageWidget = new QWidget;
    QWidget *thirdPageWidget = new QWidget;
    QStackedWidget *stackedWidget = new QStackedWidget;
    stackedWidget->addWidget(firstPageWidget);
    stackedWidget->addWidget(secondPageWidget);
    stackedWidget->addWidget(thirdPageWidget);
    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(stackedWidget);
    setLayout(layout);

QStackedWidget provides no intrinsic means for the user to switch page. This is typically done through a QComboBox 或 QListWidget that stores the titles of the QStackedWidget's pages. For example:

    QComboBox *pageComboBox = new QComboBox;
    pageComboBox->addItem(tr("Page 1"));
    pageComboBox->addItem(tr("Page 2"));
    pageComboBox->addItem(tr("Page 3"));
    connect(pageComboBox, QOverload<int>::of(&QComboBox::activated),
            stackedWidget, &QStackedWidget::setCurrentIndex);

When populating a stacked widget, the widgets are added to an internal list. The indexOf () function returns the index of a widget in that list. The widgets can either be added to the end of the list using the addWidget () function, or inserted at a given index using the insertWidget () 函數。 removeWidget () function removes a widget from the stacked widget. The number of widgets contained in the stacked widget can be obtained using the count () 函數。

The widget () function returns the widget at a given index position. The index of the widget that is shown on screen is given by currentIndex () and can be changed using setCurrentIndex (). In a similar manner, the currently shown widget can be retrieved using the currentWidget () 函數，和變更使用 setCurrentWidget () 函數。

Whenever the current widget in the stacked widget changes or a widget is removed from the stacked widget, the currentChanged () 和 widgetRemoved () signals are emitted respectively.

另請參閱 QStackedLayout and QTabWidget .

特性文檔編製

count : const int

This property holds the number of widgets contained by this stacked widget

默認情況下，此特性包含 0 值。

訪問函數：

int	count () const

另請參閱 currentIndex () 和 widget ().

currentIndex : int

此特性保持可見 Widget 的索引位置

當前索引為 -1，若沒有當前 Widget。

By default, this property contains a value of -1 because the stack is initially empty.

訪問函數：

int	currentIndex () const
void	setCurrentIndex (int index )

通知程序信號：

void	currentChanged (int index )

另請參閱 currentWidget () 和 indexOf ().

成員函數文檔編製

QStackedWidget:: QStackedWidget ( QWidget * parent = nullptr)

Constructs a QStackedWidget with the given parent .

另請參閱 addWidget () 和 insertWidget ().

`[signal]` void QStackedWidget:: currentChanged ( int index )

This signal is emitted whenever the current widget changes.

The parameter holds the index of the new current widget, or -1 if there isn't a new one (for example, if there are no widgets in the QStackedWidget ).

注意： 通知程序信號對於特性 currentIndex .

另請參閱 currentWidget () 和 setCurrentWidget ().

`[slot]` void QStackedWidget:: setCurrentWidget ( QWidget * widget )

Sets the current widget to be the specified widget . The new current widget must already be contained in this stacked widget.

另請參閱 currentWidget () 和 setCurrentIndex ().

`[signal]` void QStackedWidget:: widgetRemoved ( int index )

This signal is emitted whenever a widget is removed. The widget's index is passed as parameter.

另請參閱 removeWidget ().

`[虛擬]` QStackedWidget:: ~QStackedWidget ()

Destroys this stacked widget, and frees any allocated resources.

int QStackedWidget:: addWidget ( QWidget * widget )

Appends the given widget 到 QStackedWidget and returns the index position. Ownership of widget 被傳遞給 QStackedWidget .

若 QStackedWidget is empty before this function is called, widget becomes the current widget.

另請參閱 insertWidget (), removeWidget ()，和 setCurrentWidget ().

QWidget *QStackedWidget:: currentWidget () const

返迴當前 Widget，或 nullptr 若沒有子級 Widget。

另請參閱 currentIndex () 和 setCurrentWidget ().

`[override virtual protected]` bool QStackedWidget:: event ( QEvent * e )

重實現： QFrame::event (QEvent *e).

int QStackedWidget:: indexOf ( QWidget * widget ) const

返迴索引為給定 widget , or -1 if the given widget is not a child of the QStackedWidget .

另請參閱 currentIndex () 和 widget ().

int QStackedWidget:: insertWidget ( int index , QWidget * widget )

插入給定 widget 在給定 index 在 QStackedWidget . Ownership of widget 被傳遞給 QStackedWidget 。若 index is out of range, the widget is appended (in which case it is the actual index of the widget that is returned).

若 QStackedWidget was empty before this function is called, the given widget becomes the current widget.

Inserting a new widget at an index less than or equal to the current index will increment the current index, but keep the current widget.

另請參閱 addWidget (), removeWidget ()，和 setCurrentWidget ().

void QStackedWidget:: removeWidget ( QWidget * widget )

移除 widget 從 QStackedWidget . i.e., widget is not deleted but simply removed from the stacked layout, causing it to be hidden.

注意： Parent object and parent widget of widget will remain the QStackedWidget . If the application wants to reuse the removed widget , then it is recommended to re-parent it.

另請參閱 addWidget (), insertWidget ()，和 currentWidget ().

返迴 Widget 按給定 index ，或 nullptr 若沒有這種 Widget。