QToolButton与图标+文字：如何中心组？(QToolButton with icon + t

I am using multiple QToolButtons in a custom QGridLayout widget. The buttons are set to display icon + text based on an assigned default QAction. The only issue is that the content (icon + text) is always left-aligned.

The content (icon + text, marked as a red box in the screenshot), should be center in the button (indicated by the blue box).

For most cases this is just fine, given that Qt automatically tries to render that button with the minimal size. However I am stretching the button to fit nicely into my QGridLayout.

QToolButton* pButton = new QToolButton(0);
pButton->addDefaultAction(pAction);
pButton->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
pButton->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);

QGridLayout *pActionAreaLayout = new QGridLayout;
pActionAreaLayout->addWidget(pSomeOtherWidget, 0, 0, 1, 2);
pActionAreaLayout->addWidget(pButton , 1, 0, 1, 1);

Is there a way to force the content to be centered in the button?

PS: I found the following comment in another forum, which however seems quite invasive and is not really clear to me yet:

You can try doing the horizontal alignment using a stylesheet, but you probably have to implement a QStyle proxy and reimplement drawControl() for QStyle::CE_ToolButtonLabel Or derive from QToolButton, overwrite paintEvent() and call the style for everything other than the label.

Answer 1:

正如我在答案建议你另外一个问题。 https://stackoverflow.com/a/28630318/1917249不要使用QToolButton，只要使用QPushButton，并且根据需要添加弹出菜单。

然后，你不会有不同的尺寸QToolButton和QPushButton部件。 你将有居中图标和文本。

弹出菜单可以容易地添加到QPushButton（仅小箭头不会被示出）

QPushButton *pushButton = new QPushButton(toolAction->icon(), "PushButton", window);
// window - widget where button is placed ( to get correct QMenu position )
QObject::connect(pushButton, &QPushButton::released, [window, pushButton, action](){
    QMenu menu;
    menu.addAction(action);
    QPoint pos = window->mapToGlobal(pushButton3->pos());
    pos += QPoint(0, pushButton->height());
    menu.exec(pos);
 });

或者，你也可以继承QPushButton并添加弹出菜单操作那里。 好多然后尝试中心与文本图标QToolButton或具有在相同尺寸QPushButton和QToolButton

对于复杂的例子，请参阅我的回答： https://stackoverflow.com/a/28630318/1917249

Answer 2:

下面的类做这项工作对我来说：

class CenteredToolButtonStyle : public QProxyStyle
{
Q_OBJECT

public:
CenteredToolButtonStyle(QToolButton* b, const QSize& sIcon);

virtual void drawItemPixmap(QPainter *painter, const QRect &rect, int, const QPixmap &pixmap) const
    override { m_pic = pixmap; m_ny = rect.y(); Draw(painter); }
virtual void drawItemText(QPainter *painter, const QRect &rect, int flags, const QPalette &pal, bool enabled,
    const QString &text, QPalette::ColorRole textRole = QPalette::NoRole) const override;
void Draw(QPainter *painter) const;

const QToolButton* B;
const QSize SICON;
mutable QString m_s;
mutable QPixmap m_pic;
mutable QRect m_r;
mutable int m_nf, m_ny;
mutable bool m_bEnabled;
mutable QPalette m_pal;
mutable QPalette::ColorRole m_textRole;
};


CenteredToolButtonStyle::CenteredToolButtonStyle(QToolButton* b, const QSize& sIcon)
: QProxyStyle(), B(b), SICON(sIcon), m_nf(0), m_bEnabled(true), m_ny(0)
{
b->setToolButtonStyle(Qt::ToolButtonTextBesideIcon);
setParent(b);
}

void CenteredToolButtonStyle::drawItemText(QPainter *painter, const QRect &rect, int flags, const QPalette &pal,
bool enabled, const QString &text, QPalette::ColorRole textRole/* = QPalette::NoRole*/) const
{
m_s = text;
m_r = rect;
m_nf = flags | Qt::AlignCenter;
m_bEnabled = enabled;
m_pal = pal;
m_textRole = textRole;
Draw(painter);
}

void CenteredToolButtonStyle::Draw(QPainter *painter) const
{
if (m_ny) {
    if (m_r.y() != m_ny) return;
    auto r = m_r;
    r.adjust(-SICON.width() - 8, m_ny = 0, -itemTextRect(B->fontMetrics(), m_r, m_nf, m_bEnabled, m_s).width(), 0);
    QProxyStyle::drawItemPixmap(painter, r, Qt::AlignCenter, m_pic);
}
QProxyStyle::drawItemText(painter, m_r, m_nf, m_pal, m_bEnabled, m_s, m_textRole);
}

示例使用：

foreach(auto b, ui.mainToolBar->findChildren<QToolButton*>()) 
    b->setStyle(new CenteredToolButtonStyle(b, ui.mainToolBar->iconSize()));

文章来源: QToolButton with icon + text: How to center both?