GroupBox: add implicitLabelWidth|Height

[ChangeLog][Controls][GroupBox] Added implicitLabelWidth and
implicitLabelHeight properties.

Change-Id: Ieae54a3b3044b306cd00f45101c6573b5291352d
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 78 insertions, 2 deletions

diff --git a/src/quicktemplates2/qquickgroupbox.cpp b/src/quicktemplates2/qquickgroupbox.cpp
index cc74cce9..490d8bdd 100644
--- a/src/quicktemplates2/qquickgroupbox.cpp
+++ b/src/quicktemplates2/qquickgroupbox.cpp
@@ -94,6 +94,9 @@ public:
     void cancelLabel();
     void executeLabel(bool complete = false);
 
+    void itemImplicitWidthChanged(QQuickItem *item) override;
+    void itemImplicitHeightChanged(QQuickItem *item) override;
+
     QString title;
     QQuickDeferredPointer<QQuickItem> label;
 };
@@ -118,11 +121,33 @@ void QQuickGroupBoxPrivate::executeLabel(bool complete)
         quickCompleteDeferred(q, labelName(), label);
 }
 
+void QQuickGroupBoxPrivate::itemImplicitWidthChanged(QQuickItem *item)
+{
+    Q_Q(QQuickGroupBox);
+    QQuickFramePrivate::itemImplicitWidthChanged(item);
+    if (item == label)
+        emit q->implicitLabelWidthChanged();
+}
+
+void QQuickGroupBoxPrivate::itemImplicitHeightChanged(QQuickItem *item)
+{
+    Q_Q(QQuickGroupBox);
+    QQuickFramePrivate::itemImplicitHeightChanged(item);
+    if (item == label)
+        emit q->implicitLabelHeightChanged();
+}
+
 QQuickGroupBox::QQuickGroupBox(QQuickItem *parent)
     : QQuickFrame(*(new QQuickGroupBoxPrivate), parent)
 {
 }
 
+QQuickGroupBox::~QQuickGroupBox()
+{
+    Q_D(QQuickGroupBox);
+    d->removeImplicitSizeListener(d->label);
+}
+
 /*!
     \qmlproperty string QtQuick.Controls::GroupBox::title
 
@@ -172,14 +197,65 @@ void QQuickGroupBox::setLabel(QQuickItem *label)
     if (!d->label.isExecuting())
         d->cancelLabel();
 
+    const qreal oldImplicitLabelWidth = implicitLabelWidth();
+    const qreal oldImplicitLabelHeight = implicitLabelHeight();
+
+    d->removeImplicitSizeListener(d->label);
     delete d->label;
     d->label = label;
-    if (label && !label->parentItem())
-        label->setParentItem(this);
+
+    if (label) {
+        if (!label->parentItem())
+            label->setParentItem(this);
+        d->addImplicitSizeListener(label);
+    }
+
+    if (!qFuzzyCompare(oldImplicitLabelWidth, implicitLabelWidth()))
+        emit implicitLabelWidthChanged();
+    if (!qFuzzyCompare(oldImplicitLabelHeight, implicitLabelHeight()))
+        emit implicitLabelHeightChanged();
     if (!d->label.isExecuting())
         emit labelChanged();
 }
 
+/*!
+    \since QtQuick.Controls 2.5 (Qt 5.12)
+    \qmlproperty real QtQuick.Controls::GroupBox::implicitLabelWidth
+    \readonly
+
+    This property holds the implicit label width.
+
+    The value is equal to \c {label ? label.implicitWidth : 0}.
+
+    \sa implicitLabelHeight
+*/
+qreal QQuickGroupBox::implicitLabelWidth() const
+{
+    Q_D(const QQuickGroupBox);
+    if (!d->label)
+        return 0;
+    return d->label->implicitWidth();
+}
+
+/*!
+    \since QtQuick.Controls 2.5 (Qt 5.12)
+    \qmlproperty real QtQuick.Controls::GroupBox::implicitLabelHeight
+    \readonly
+
+    This property holds the implicit label height.
+
+    The value is equal to \c {label ? label.implicitHeight : 0}.
+
+    \sa implicitLabelWidth
+*/
+qreal QQuickGroupBox::implicitLabelHeight() const
+{
+    Q_D(const QQuickGroupBox);
+    if (!d->label)
+        return 0;
+    return d->label->implicitHeight();
+}
+
 void QQuickGroupBox::componentComplete()
 {
     Q_D(QQuickGroupBox);