QQuickControl: update baseline offset automatically

...unless explicitly defined. All buttons repeated the same binding.

[ChangeLog][Controls][Control] Unless explicitly specified, baselineOffset
is now automatically updated based on the top padding of the control and
the baselineOffset of the contentItem. Styles no longer need to specify
the baselineOffset in QML.

Change-Id: I9c6f61371fee05a06b5dd31b27d8baf9da0bdeeb
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 54 insertions, 0 deletions

diff --git a/src/quicktemplates2/qquickcontrol.cpp b/src/quicktemplates2/qquickcontrol.cpp
index fd206eea..32147329 100644
--- a/src/quicktemplates2/qquickcontrol.cpp
+++ b/src/quicktemplates2/qquickcontrol.cpp
@@ -107,6 +107,7 @@ QQuickControlPrivate::ExtraData::ExtraData()
       hasLeftPadding(false),
       hasRightPadding(false),
       hasBottomPadding(false),
+      hasBaselineOffset(false),
       topPadding(0),
       leftPadding(0),
       rightPadding(0),
@@ -145,6 +146,12 @@ QQuickControlPrivate::~QQuickControlPrivate()
 #endif
 }
 
+void QQuickControlPrivate::init()
+{
+    Q_Q(QQuickControl);
+    QObject::connect(q, &QQuickItem::baselineOffsetChanged, q, &QQuickControl::baselineOffsetChanged);
+}
+
 #if QT_CONFIG(quicktemplates2_multitouch)
 bool QQuickControlPrivate::acceptTouch(const QTouchEvent::TouchPoint &point)
 {
@@ -337,16 +344,21 @@ void QQuickControlPrivate::setContentItem_helper(QQuickItem *item, bool notify)
         cancelContentItem();
 
     QQuickItem *oldContentItem = contentItem;
+    if (oldContentItem)
+        disconnect(oldContentItem, &QQuickItem::baselineOffsetChanged, this, &QQuickControlPrivate::updateBaselineOffset);
+
     contentItem = item;
     q->contentItemChange(item, oldContentItem);
     delete oldContentItem;
 
     if (item) {
+        connect(contentItem, &QQuickItem::baselineOffsetChanged, this, &QQuickControlPrivate::updateBaselineOffset);
         if (!item->parentItem())
             item->setParentItem(q);
         if (componentComplete)
             resizeContent();
     }
+    updateBaselineOffset();
 
     if (notify && !contentItem.isExecuting())
         emit q->contentItemChanged();
@@ -705,14 +717,30 @@ void QQuickControlPrivate::executeBackground(bool complete)
         quickCompleteDeferred(q, backgroundName(), background);
 }
 
+void QQuickControlPrivate::updateBaselineOffset()
+{
+    Q_Q(QQuickControl);
+    if (extra.isAllocated() && extra.value().hasBaselineOffset)
+        return;
+
+    if (!contentItem)
+        q->QQuickItem::setBaselineOffset(0);
+    else
+        q->QQuickItem::setBaselineOffset(getTopPadding() + contentItem->baselineOffset());
+}
+
 QQuickControl::QQuickControl(QQuickItem *parent)
     : QQuickItem(*(new QQuickControlPrivate), parent)
 {
+    Q_D(QQuickControl);
+    d->init();
 }
 
 QQuickControl::QQuickControl(QQuickControlPrivate &dd, QQuickItem *parent)
     : QQuickItem(dd, parent)
 {
+    Q_D(QQuickControl);
+    d->init();
 }
 
 void QQuickControl::itemChange(QQuickItem::ItemChange change, const QQuickItem::ItemChangeData &value)
@@ -1388,6 +1416,30 @@ void QQuickControl::setContentItem(QQuickItem *item)
     d->setContentItem_helper(item, true);
 }
 
+qreal QQuickControl::baselineOffset() const
+{
+    Q_D(const QQuickControl);
+    return d->baselineOffset;
+}
+
+void QQuickControl::setBaselineOffset(qreal offset)
+{
+    Q_D(QQuickControl);
+    d->extra.value().hasBaselineOffset = true;
+    QQuickItem::setBaselineOffset(offset);
+}
+
+void QQuickControl::resetBaselineOffset()
+{
+    Q_D(QQuickControl);
+    if (!d->extra.isAllocated() || !d->extra.value().hasBaselineOffset)
+        return;
+
+    if (d->extra.isAllocated())
+        d->extra.value().hasBaselineOffset = false;
+    d->updateBaselineOffset();
+}
+
 /*!
     \since QtQuick.Controls 2.3 (Qt 5.10)
     \qmlproperty palette QtQuick.Controls::Control::palette
@@ -1527,6 +1579,7 @@ void QQuickControl::componentComplete()
     QQuickItem::componentComplete();
     d->resizeBackground();
     d->resizeContent();
+    d->updateBaselineOffset();
     if (!d->hasLocale)
         d->locale = QQuickControlPrivate::calcLocale(d->parentItem);
 #if QT_CONFIG(quicktemplates2_hover)
@@ -1708,6 +1761,7 @@ void QQuickControl::paddingChange(const QMarginsF &newPadding, const QMarginsF &
     Q_UNUSED(newPadding);
     Q_UNUSED(oldPadding);
     d->resizeContent();
+    d->updateBaselineOffset();
 }
 
 void QQuickControl::contentItemChange(QQuickItem *newItem, QQuickItem *oldItem)