Add QMainWindow::resizeDocks

This API allows to programatically resize QDockWidgets

Task-number: QTBUG-32001
Change-Id: I58072a391f8e7f325a26745b5bedd3fe49508e91
Reviewed-by: Jocelyn Turcotte (Woboq GmbH) <jturcotte@woboq.com>

4 files changed, 80 insertions, 0 deletions

diff --git a/src/widgets/widgets/qdockarealayout.cpp b/src/widgets/widgets/qdockarealayout.cpp
index c61984a457..0a00086138 100644
--- a/src/widgets/widgets/qdockarealayout.cpp
+++ b/src/widgets/widgets/qdockarealayout.cpp
@@ -3101,6 +3101,53 @@ void QDockAreaLayout::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
         remove(index);
 }
 
+void QDockAreaLayout::resizeDocks(const QList<QDockWidget *> &docks,
+                                  const QList<int> &sizes, Qt::Orientation o)
+{
+    if (docks.count() != sizes.count()) {
+        qWarning("QMainWidget::resizeDocks: size of the lists are not the same");
+        return;
+    }
+    int count = docks.count();
+    fallbackToSizeHints = false;
+    for (int i = 0; i < count; ++i) {
+        QList<int> path = indexOf(docks[i]);
+        if (path.isEmpty()) {
+            qWarning("QMainWidget::resizeDocks: one QDockWidget is not part of the layout");
+            continue;
+        }
+        int size = sizes[i];
+        if (size <= 0) {
+            qWarning("QMainWidget::resizeDocks: all sizes need to be larger than 0");
+            size = 1;
+        }
+
+        while (path.size() > 1) {
+            QDockAreaLayoutInfo *info = this->info(path);
+            if (!info->tabbed && info->o == o) {
+                info->item_list[path.last()].size = size;
+                int totalSize = 0;
+                foreach (const QDockAreaLayoutItem &item, info->item_list) {
+                    if (!item.skip()) {
+                        if (totalSize != 0)
+                            totalSize += sep;
+                        totalSize += item.size == -1 ? pick(o, item.sizeHint()) : item.size;
+                    }
+                }
+                size = totalSize;
+            }
+            path.removeLast();
+        }
+
+        const int dockNum = path.first();
+        Q_ASSERT(dockNum < QInternal::DockCount);
+        QRect &r = this->docks[dockNum].rect;
+        QSize s = r.size();
+        rpick(o, s) = size;
+        r.setSize(s);
+    }
+}
+
 void QDockAreaLayout::splitDockWidget(QDockWidget *after,
                                                QDockWidget *dockWidget,
                                                Qt::Orientation orientation)
diff --git a/src/widgets/widgets/qdockarealayout_p.h b/src/widgets/widgets/qdockarealayout_p.h
index 93b005f64f..5d352f0124 100644
--- a/src/widgets/widgets/qdockarealayout_p.h
+++ b/src/widgets/widgets/qdockarealayout_p.h
@@ -268,6 +268,7 @@ public:
     void splitDockWidget(QDockWidget *after, QDockWidget *dockWidget,
                          Qt::Orientation orientation);
     void tabifyDockWidget(QDockWidget *first, QDockWidget *second);
+    void resizeDocks(const QList<QDockWidget *> &docks, const QList<int> &sizes, Qt::Orientation o);
 
     void apply(bool animate);
 
diff --git a/src/widgets/widgets/qmainwindow.cpp b/src/widgets/widgets/qmainwindow.cpp
index 5d53e7def4..ff4bb3cc98 100644
--- a/src/widgets/widgets/qmainwindow.cpp
+++ b/src/widgets/widgets/qmainwindow.cpp
@@ -1237,6 +1237,35 @@ void QMainWindow::removeDockWidget(QDockWidget *dockwidget)
 Qt::DockWidgetArea QMainWindow::dockWidgetArea(QDockWidget *dockwidget) const
 { return d_func()->layout->dockWidgetArea(dockwidget); }
 
+
+/*!
+    \since 5.6
+    Resizes the dock widgets in the list \a docks to the corresponding size in
+    pixels from the list \a sizes. If \a orientation is Qt::Horizontal, adjusts
+    the width, otherwise adjusts the height of the dock widgets.
+    The sizes will be adjusted such that the maximum and the minimum sizes are
+    respected and the QMainWindow itself will not be resized.
+    Any additional/missing space is distributed amongst the widgets according
+    to the relative weight of the sizes.
+
+    Example:
+    \code
+    resizeDocks({blueWidget, yellowWidget}, {20 , 40}, Qt::Horizontal);
+    \endcode
+    If the blue and the yellow widget are nested on the same level they will be
+    resized such that the yellowWidget is twice as big as the blueWidget
+
+    If some widgets are grouped in tabs, only one widget per group should be
+    specified. Widgets not in the list might be changed to repect the constraints.
+*/
+void QMainWindow::resizeDocks(const QList<QDockWidget *> &docks,
+                              const QList<int> &sizes, Qt::Orientation orientation)
+{
+    d_func()->layout->layoutState.dockAreaLayout.resizeDocks(docks, sizes, orientation);
+    d_func()->layout->invalidate();
+}
+
+
 #endif // QT_NO_DOCKWIDGET
 
 /*!
diff --git a/src/widgets/widgets/qmainwindow.h b/src/widgets/widgets/qmainwindow.h
index ab6ee22748..70d78a7904 100644
--- a/src/widgets/widgets/qmainwindow.h
+++ b/src/widgets/widgets/qmainwindow.h
@@ -165,6 +165,9 @@ public:
     bool restoreDockWidget(QDockWidget *dockwidget);
 
     Qt::DockWidgetArea dockWidgetArea(QDockWidget *dockwidget) const;
+
+    void resizeDocks(const QList<QDockWidget *> &docks,
+                     const QList<int> &sizes, Qt::Orientation orientation);
 #endif // QT_NO_DOCKWIDGET
 
     QByteArray saveState(int version = 0) const;