Qt容器組件（一）之QGroupBox、QScrollArea、QToolBox、QTabWidget

QT中有九種容器組件，分別是組合框QGroupBox、滾動區QScrollArea、工具箱QToolBox、選項卡QTabWidget、控件棧QWidgetStack、框架QFrame、組件QWidget、MDI窗口顯示區QMdiArea、停靠窗口QDockWidget。
本博主要介紹：組合框QGroupBox、滾動區QScrollArea、工具箱QToolBox、選項卡QTabWidget

一、QGroupBox分組框

　　QGroupBox為構建分組框提供了支持。分組框通常帶有一個邊框和一個標題欄，作為容器部件來使用，在其中可以布置各種窗口部件。分組框的標題通常在上方顯示，其位置可以設置為靠左、居中、靠右、自動調整這幾種方式之一。位於分組框之中的窗口部件可以獲得應用程序的焦點，位於分組框之內的窗口部件是分組框的子窗口，通常使用addWidget()方法把子窗口部件加入到分組框之中。

　　Qt示例：\Examples\Qt-5.9.3\widgets\widgets\groupbox中提供了QGroupBox的示例

　　

（1）屬性

Q_PROPERTY(QString title READ title WRITE setTitle)
Q_PROPERTY(Qt::Alignment alignment READ alignment WRITE setAlignment)
Q_PROPERTY(bool flat READ isFlat WRITE setFlat)
Q_PROPERTY(bool checkable READ isCheckable WRITE setCheckable)
Q_PROPERTY(bool checked READ isChecked WRITE setChecked DESIGNABLE isCheckable NOTIFY toggled USER true)

（2）信號、槽

public Q_SLOTS:
    void setChecked(bool checked);

Q_SIGNALS:
    void clicked(bool checked = false);
    void toggled(bool);

（3）示例

#include "mainwindow.h"
#include <QApplication>

#include <QObject>
#include <QGroupBox>
#include <QPushButton>
#include <QCheckBox>
#include <QRadioButton>
#include <QVBoxLayout>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QGroupBox *pGroupBox = new QGroupBox(QObject::tr("GroupBox test"));
    QPushButton *pBtn = new QPushButton(QObject::tr("button")) ;
    QCheckBox* pCheckBox = new QCheckBox(QObject::tr("checkbox test"));
    QRadioButton* pRadio = new QRadioButton(QObject::tr("radiobtn test"));
    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(pBtn);
    layout->addWidget(pCheckBox);
    layout->addWidget(pRadio);
    pGroupBox->setLayout(layout);

    pGroupBox->setCheckable(true);
    pGroupBox->show();
    return a.exec();
}

二、QScrollArea滾動區

　　QScrollArea滾動區組件用來顯示子控件的內容的框架，如果子控件的尺寸超過了框架的大小，可以使用滾動條，方便查看整個子控件。QScrollArea 可以給任何QWidget添加滾動條，但一般自定義窗體添加滾動條不顯示。　

　　class QScrollArea : public QAbstractScrollArea

　　class QAbstractScrollArea : public QFrame

（1）屬性

class Q_WIDGETS_EXPORT QAbstractScrollArea : public QFrame
{
    Q_OBJECT

    Q_PROPERTY(Qt::ScrollBarPolicy verticalScrollBarPolicy READ verticalScrollBarPolicy WRITE setVerticalScrollBarPolicy)
    Q_PROPERTY(Qt::ScrollBarPolicy horizontalScrollBarPolicy READ horizontalScrollBarPolicy WRITE setHorizontalScrollBarPolicy)
    Q_PROPERTY(SizeAdjustPolicy sizeAdjustPolicy READ sizeAdjustPolicy WRITE setSizeAdjustPolicy)
  .......................................................    
}

class Q_WIDGETS_EXPORT QScrollArea : public QAbstractScrollArea
{
    Q_OBJECT
    Q_PROPERTY(bool widgetResizable READ widgetResizable WRITE setWidgetResizable)
    Q_PROPERTY(Qt::Alignment alignment READ alignment WRITE setAlignment)
    ................................................
}

（2）常用成員函數　

　　QScrollArea：：QScrollArea（QWidget *parent = 0）

　　構造一個父對象為parent的ScrollArea

　　void QScrollArea：：setWidget（QWidget *widget）

　　設置控件widget為QScrollArea組件的子控件

　　QWidget *SCrollArea：：takeWidget（）

　　刪除QScrollArea的子控件

 　　QWidget *QScrollArea：：widget（）const

　　返回QScrollArea的子控件

（3）示例

#include "mainwindow.h"
#include <QApplication>

#include <QObject>
#include <QGroupBox>
#include <QPushButton>
#include <QCheckBox>
#include <QRadioButton>
#include <QVBoxLayout>
#include <QScrollArea>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    QGroupBox *pGroupBox = new QGroupBox(QObject::tr("GroupBox test"), &w);
    QPushButton *pBtn = new QPushButton(QObject::tr("button")) ;
    QCheckBox* pCheckBox = new QCheckBox(QObject::tr("checkbox test"));
    QRadioButton* pRadio = new QRadioButton(QObject::tr("radiobtn test"));

    QScrollArea* pSCrollArea = new QScrollArea(&w);

    QVBoxLayout *layout = new QVBoxLayout;
    layout->addWidget(pBtn);
    layout->addWidget(pCheckBox);
    layout->addWidget(pRadio);
    pGroupBox->setLayout(layout);

    pGroupBox->setCheckable(true);  // 將groupbox添加到滾動區
    pSCrollArea->setWidgetResizable(true);  // 設置滾動區大小
    pSCrollArea->setBackgroundRole(QPalette::Dark);
    pSCrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    pSCrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    pSCrollArea->setWidget(pGroupBox);

    w.setCentralWidget(pSCrollArea);
    w.setWindowTitle("container test");
    w.setMinimumSize(50,50);
    w.show();
    return a.exec();
}

三、QToolBox工具箱

　　QToolBox提供了一系列的頁和隔間，就像Qt Creator中的工具箱一樣。

（1）屬性

class Q_WIDGETS_EXPORT QToolBox : public QFrame
{
    Q_OBJECT
    Q_PROPERTY(int currentIndex READ currentIndex WRITE setCurrentIndex NOTIFY currentChanged)
    Q_PROPERTY(int count READ count)
    。。。。。。。。。。。。。。。。。。。。
｝

（2）常用函數

　　添加項，設置項的圖標、文本、enable、tooltip等

　　int addItem(QWidget *widget, const QString &text);
    int addItem(QWidget *widget, const QIcon &icon, const QString &text);
    int insertItem(int index, QWidget *widget, const QString &text);
    int insertItem(int index, QWidget *widget, const QIcon &icon, const QString &text);

    void removeItem(int index);

    void setItemEnabled(int index, bool enabled);
    bool isItemEnabled(int index) const;

    void setItemText(int index, const QString &text);
    QString itemText(int index) const;

    void setItemIcon(int index, const QIcon &icon);
    QIcon itemIcon(int index) const;

#ifndef QT_NO_TOOLTIP
    void setItemToolTip(int index, const QString &toolTip);
    QString itemToolTip(int index) const;
#endif

    int currentIndex() const;
    QWidget *currentWidget() const;
    QWidget *widget(int index) const;
    int indexOf(QWidget *widget) const;
    int count() const;

public Q_SLOTS:
    void setCurrentIndex(int index);
    void setCurrentWidget(QWidget *widget);

Q_SIGNALS:
    void currentChanged(int index);

（3）示例

　　思想：QToolBox中的每一項為QWidget

　　　　　QWidegt的組成:QVBoxLayout，每個QVBoxLayout中包含兩個QToolButton

#include "mainwindow.h"
#include <QApplication>
#include <QToolBox>
#include <QVBoxLayout>
#include <QToolButton>
#include <QGroupBox>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    QWidget *pGroup1 = new QWidget;

    QToolButton *pBtn1 = new QToolButton;
    pBtn1->setText("apple");
    pBtn1->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn1->setAutoRaise(true);
    pBtn1->setArrowType(Qt::ArrowType::DownArrow);

    QToolButton *pBtn2 = new QToolButton;
    pBtn2->setText("babala");
    pBtn2->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn2->setAutoRaise(true);

    QVBoxLayout *pLayout1 = new QVBoxLayout(pGroup1);
    pLayout1->setMargin(10);
    pLayout1->setAlignment(Qt::AlignmentFlag::AlignLeft);
    pLayout1->addWidget(pBtn1);
    pLayout1->addWidget(pBtn2);

    //////////////////////////////////////
    QWidget *pGroup2 = new QWidget;
    QToolButton *pBtn3 = new QToolButton;
    pBtn3->setText("HUAWEI");
    pBtn3->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn3->setAutoRaise(true);

    QToolButton *pBtn4 = new QToolButton;
    pBtn4->setText("IXOAMI");
    pBtn4->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn4->setAutoRaise(true);

    QVBoxLayout *pLayout2 = new QVBoxLayout(pGroup2);
    pLayout2->setMargin(10);
    pLayout2->setAlignment(Qt::AlignmentFlag::AlignLeft);
    pLayout2->addWidget(pBtn3);
    pLayout2->addWidget(pBtn4);

    QToolBox* pToolBox = new QToolBox(&w);
    pToolBox->addItem(pGroup1, "fruit");   // 當第一個參數為QToolBtn時顯示不對
    pToolBox->addItem(pGroup2, "telephone");

    w.setCentralWidget(pToolBox);
    w.setWindowTitle("container test");
    w.setMinimumSize(50,50);
    w.show();
    return a.exec();
}

四、QTabWidget選項卡

　　QTabWidget選項卡組件頂部或底部有一個標簽選項欄，每個標簽選項都有一個頁面，選擇哪個頁面，只需單擊對應的標簽即可，或按指定ALT+字母快捷鍵組合即可。

（1）屬性

　　TabPosition、TabShape、currentIndex、count、iconSize、TextElideMode、usesScrollButtons、documentMode、tabsClosable、movable、tabBarAutoHide

class Q_WIDGETS_EXPORT QTabWidget : public QWidget
{
    Q_OBJECT
    Q_PROPERTY(TabPosition tabPosition READ tabPosition WRITE setTabPosition)
    Q_PROPERTY(TabShape tabShape READ tabShape WRITE setTabShape)
    Q_PROPERTY(int currentIndex READ currentIndex WRITE setCurrentIndex NOTIFY currentChanged)
    Q_PROPERTY(int count READ count)
    Q_PROPERTY(QSize iconSize READ iconSize WRITE setIconSize)
    Q_PROPERTY(Qt::TextElideMode elideMode READ elideMode WRITE setElideMode)
    Q_PROPERTY(bool usesScrollButtons READ usesScrollButtons WRITE setUsesScrollButtons)
    Q_PROPERTY(bool documentMode READ documentMode WRITE setDocumentMode)
    Q_PROPERTY(bool tabsClosable READ tabsClosable WRITE setTabsClosable)
    Q_PROPERTY(bool movable READ isMovable WRITE setMovable)
    Q_PROPERTY(bool tabBarAutoHide READ tabBarAutoHide WRITE setTabBarAutoHide)
}

（2）信號、槽

public Q_SLOTS:
    void setCurrentIndex(int index);
    void setCurrentWidget(QWidget *widget);

Q_SIGNALS:
    void currentChanged(int index);
    void tabCloseRequested(int index);
    void tabBarClicked(int index);
    void tabBarDoubleClicked(int index);

（3）示例

#include "mainwindow.h"
#include <QApplication>
#include <QTabWidget>
#include <QToolButton>
#include <QVBoxLayout>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    QWidget *pGroup1 = new QWidget;

    QToolButton *pBtn1 = new QToolButton;
    pBtn1->setText("apple");
    pBtn1->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn1->setAutoRaise(true);
    pBtn1->setArrowType(Qt::ArrowType::DownArrow);

    QToolButton *pBtn2 = new QToolButton;
    pBtn2->setText("babala");
    pBtn2->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn2->setAutoRaise(true);

    QVBoxLayout *pLayout1 = new QVBoxLayout(pGroup1);
    pLayout1->setMargin(10);
    pLayout1->setAlignment(Qt::AlignmentFlag::AlignLeft);
    pLayout1->addWidget(pBtn1);
    pLayout1->addWidget(pBtn2);

    //////////////////////////////////////
    QWidget *pGroup2 = new QWidget;
    QToolButton *pBtn3 = new QToolButton;
    pBtn3->setText("HUAWEI");
    pBtn3->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn3->setAutoRaise(true);

    QToolButton *pBtn4 = new QToolButton;
    pBtn4->setText("IXOAMI");
    pBtn4->setToolButtonStyle(Qt::ToolButtonStyle::ToolButtonTextBesideIcon);
    pBtn4->setAutoRaise(true);

    QVBoxLayout *pLayout2 = new QVBoxLayout(pGroup2);
    pLayout2->setMargin(10);
    pLayout2->setAlignment(Qt::AlignmentFlag::AlignLeft);
    pLayout2->addWidget(pBtn3);
    pLayout2->addWidget(pBtn4);

    QTabWidget *pTab = new QTabWidget(&w);
    pTab->addTab(pGroup1, "fruit");
    pTab->addTab(pGroup2, "telephone");

    w.setCentralWidget(pTab);
    w.setWindowTitle("container test");
    w.setMinimumSize(50,50);
    w.show();
    return a.exec();
}