Fixed and improved the example code

2 files changed, 58 insertions, 14 deletions

diff --git a/examples/layouts/flowlayout/flowlayout.cpp b/examples/layouts/flowlayout/flowlayout.cpp
index d1e857d..be6b476 100644
--- a/examples/layouts/flowlayout/flowlayout.cpp
+++ b/examples/layouts/flowlayout/flowlayout.cpp
@@ -43,16 +43,16 @@
 
 #include "flowlayout.h"
 
-FlowLayout::FlowLayout(QWidget *parent, int margin, int spacing)
-    : QLayout(parent)
+FlowLayout::FlowLayout(QWidget *parent, int margin, int hSpacing, int vSpacing)
+    : QLayout(parent), m_hSpace(hSpacing), m_vSpace(vSpacing)
 {
     setMargin(margin);
-    setSpacing(spacing);
 }
 
-FlowLayout::FlowLayout(int spacing)
+FlowLayout::FlowLayout(int margin, int hSpacing, int vSpacing)
+    : m_hSpace(hSpacing), m_vSpace(vSpacing)
 {
-    setSpacing(spacing);
+    setMargin(margin);
 }
 
 FlowLayout::~FlowLayout()
@@ -67,6 +67,24 @@ void FlowLayout::addItem(QLayoutItem *item)
     itemList.append(item);
 }
 
+int FlowLayout::horizontalSpacing() const
+{
+    if (m_hSpace >= 0) {
+        return m_hSpace;
+    } else {
+        return smartSpacing(QStyle::PM_LayoutHorizontalSpacing);
+    }
+}
+
+int FlowLayout::verticalSpacing() const
+{
+    if (m_vSpace >= 0) {
+        return m_vSpace;
+    } else {
+        return smartSpacing(QStyle::PM_LayoutVerticalSpacing);
+    }
+}
+
 int FlowLayout::count() const
 {
     return itemList.size();
@@ -125,20 +143,27 @@ QSize FlowLayout::minimumSize() const
 
 int FlowLayout::doLayout(const QRect &rect, bool testOnly) const
 {
-    int x = rect.x();
-    int y = rect.y();
+    int left, top, right, bottom;
+    getContentsMargins(&left, &top, &right, &bottom);
+    QRect effectiveRect = rect.adjusted(+left, +top, -right, -bottom);
+    int x = effectiveRect.x();
+    int y = effectiveRect.y();
     int lineHeight = 0;
 
     QLayoutItem *item;
     foreach (item, itemList) {
         QWidget *wid = item->widget();
-        int spaceX = spacing() + wid->style()->layoutSpacing(
+        int spaceX = horizontalSpacing();
+        if (spaceX == -1)
+            spaceX = wid->style()->layoutSpacing(
                 QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Horizontal);
-        int spaceY = spacing() + wid->style()->layoutSpacing(
+        int spaceY = verticalSpacing();
+        if (spaceY == -1)
+            spaceY = wid->style()->layoutSpacing(
                 QSizePolicy::PushButton, QSizePolicy::PushButton, Qt::Vertical);
         int nextX = x + item->sizeHint().width() + spaceX;
-        if (nextX - spaceX > rect.right() && lineHeight > 0) {
-            x = rect.x();
+        if (nextX - spaceX > effectiveRect.right() && lineHeight > 0) {
+            x = effectiveRect.x();
             y = y + lineHeight + spaceY;
             nextX = x + item->sizeHint().width() + spaceX;
             lineHeight = 0;
@@ -150,5 +175,19 @@ int FlowLayout::doLayout(const QRect &rect, bool testOnly) const
         x = nextX;
         lineHeight = qMax(lineHeight, item->sizeHint().height());
     }
-    return y + lineHeight - rect.y();
+    return y + lineHeight - rect.y() + bottom;
 }
+
+int FlowLayout::smartSpacing(QStyle::PixelMetric pm) const
+{
+    QObject *parent = this->parent();
+    if (!parent) {
+        return -1;
+    } else if (parent->isWidgetType()) {
+        QWidget *pw = static_cast<QWidget *>(parent);
+        return pw->style()->pixelMetric(pm, 0, pw);
+    } else {
+        return static_cast<QLayout *>(parent)->spacing();
+    }
+}
+
diff --git a/examples/layouts/flowlayout/flowlayout.h b/examples/layouts/flowlayout/flowlayout.h
index f864d8e..9940e55 100644
--- a/examples/layouts/flowlayout/flowlayout.h
+++ b/examples/layouts/flowlayout/flowlayout.h
@@ -49,11 +49,13 @@
 class FlowLayout : public QLayout
 {
 public:
-    FlowLayout(QWidget *parent, int margin = -1, int spacing = 0);
-    FlowLayout(int spacing = 0);
+    FlowLayout(QWidget *parent, int margin = -1, int hSpacing = -1, int vSpacing = -1);
+    FlowLayout(int margin = -1, int hSpacing = -1, int vSpacing = -1);
     ~FlowLayout();
 
     void addItem(QLayoutItem *item);
+    int horizontalSpacing() const;
+    int verticalSpacing() const;
     Qt::Orientations expandingDirections() const;
     bool hasHeightForWidth() const;
     int heightForWidth(int) const;
@@ -66,8 +68,11 @@ public:
 
 private:
     int doLayout(const QRect &rect, bool testOnly) const;
+    int smartSpacing(QStyle::PixelMetric pm) const;
 
     QList<QLayoutItem *> itemList;
+    int m_hSpace;
+    int m_vSpace;
 };
 
 #endif