DialogButtonBox: fix layout regression

In testbench, the settings dialog buttons were wrong laid out.

Change-Id: I3d62d5cc9d6c21a15df70a392e9b1a9d762ff3c6
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

2 files changed, 30 insertions, 1 deletions

diff --git a/src/quicktemplates2/qquickdialogbuttonbox.cpp b/src/quicktemplates2/qquickdialogbuttonbox.cpp
index 5e555da3..98437500 100644
--- a/src/quicktemplates2/qquickdialogbuttonbox.cpp
+++ b/src/quicktemplates2/qquickdialogbuttonbox.cpp
@@ -204,6 +204,7 @@ QQuickDialogButtonBoxPrivate::QQuickDialogButtonBoxPrivate()
       buttonLayout(platformButtonLayout()),
       delegate(nullptr)
 {
+    changeTypes |= ImplicitWidth | ImplicitHeight;
 }
 
 void QQuickDialogButtonBoxPrivate::itemImplicitWidthChanged(QQuickItem *item)
@@ -268,7 +269,8 @@ void QQuickDialogButtonBoxPrivate::updateLayout()
     const int valign = alignment & Qt::AlignVertical_Mask;
 
     QVector<QQuickAbstractButton *> buttons;
-    const qreal itemWidth = (contentWidth - qMax(0, count - 1) * spacing) / count;
+    const qreal cw = (alignment & Qt::AlignHorizontal_Mask) == 0 ? q->availableWidth() : contentWidth;
+    const qreal itemWidth = (cw - qMax(0, count - 1) * spacing) / count;
 
     for (int i = 0; i < count; ++i) {
         QQuickItem *item = q->itemAt(i);
diff --git a/tests/auto/controls/data/tst_dialogbuttonbox.qml b/tests/auto/controls/data/tst_dialogbuttonbox.qml
index 27989703..ed181c5b 100644
--- a/tests/auto/controls/data/tst_dialogbuttonbox.qml
+++ b/tests/auto/controls/data/tst_dialogbuttonbox.qml
@@ -248,4 +248,31 @@ TestCase {
         verify(implicitContentWidth > control.leftPadding + control.rightPadding)
         verify(control.implicitWidth >= implicitContentWidth, qsTr("implicit width (%1) is less than content width (%2)").arg(control.implicitWidth).arg(implicitContentWidth))
     }
+
+    Component {
+        id: okCancelBox
+        DialogButtonBox {
+            Button {
+                text: qsTr("OK")
+            }
+            Button {
+                text: qsTr("Cancel")
+            }
+        }
+    }
+
+    function test_buttonSize() {
+        var control = createTemporaryObject(okCancelBox, testCase)
+        verify(control)
+
+        var okButton = control.itemAt(0)
+        verify(okButton)
+        verify(okButton.width > 0)
+
+        var cancelButton = control.itemAt(1)
+        verify(cancelButton)
+        verify(cancelButton.width > 0)
+
+        compare(okButton.width + cancelButton.width, control.availableWidth - control.spacing)
+    }
 }