Mostly finished work on Widget::containerSizeChanged().

8 files changed, 110 insertions, 6 deletions

diff --git a/dw/ruler.cc b/dw/ruler.cc
index 5525f21b..3d3bc0b8 100644
--- a/dw/ruler.cc
+++ b/dw/ruler.cc
@@ -51,6 +51,11 @@ bool Ruler::isBlockLevel ()
    return true;
 }
 
+bool Ruler::usesAvailWidth ()
+{
+   return true;
+}
+
 void Ruler::draw (core::View *view, core::Rectangle *area)
 {
    drawWidgetBox (view, area, false);
diff --git a/dw/ruler.hh b/dw/ruler.hh
index eea1f952..1f2e80b0 100644
--- a/dw/ruler.hh
+++ b/dw/ruler.hh
@@ -18,6 +18,7 @@ class Ruler: public core::Widget
 protected:
    void sizeRequestImpl (core::Requisition *requisition);
    void getExtremesImpl (core::Extremes *extremes);
+   bool usesAvailWidth ();
    void draw (core::View *view, core::Rectangle *area);
 
 public:
diff --git a/dw/table.cc b/dw/table.cc
index 6c9fa19e..c968627d 100644
--- a/dw/table.cc
+++ b/dw/table.cc
@@ -255,6 +255,11 @@ int Table::getAvailWidthOfChild (Widget *child, bool forceValue)
    return width;
 }
 
+bool Table::usesAvailWidth ()
+{
+   return true;
+}
+
 bool Table::isBlockLevel ()
 {
    return true;
diff --git a/dw/table.hh b/dw/table.hh
index 847327c9..03eb410d 100644
--- a/dw/table.hh
+++ b/dw/table.hh
@@ -427,6 +427,7 @@ protected:
    void resizeDrawImpl ();
 
    int getAvailWidthOfChild (Widget *child, bool forceValue);
+   bool usesAvailWidth ();
 
    bool isBlockLevel ();
 
diff --git a/dw/textblock.cc b/dw/textblock.cc
index ea8af331..4601a5c4 100644
--- a/dw/textblock.cc
+++ b/dw/textblock.cc
@@ -607,6 +607,11 @@ void Textblock::sizeAllocateImpl (core::Allocation *allocation)
    }
 }
 
+bool Textblock::usesAvailWidth ()
+{
+   return true;
+}
+
 void Textblock::resizeDrawImpl ()
 {
    DBG_OBJ_MSG ("draw", 0, "<b>resizeDrawImpl</b> ()");
diff --git a/dw/textblock.hh b/dw/textblock.hh
index bb2e6ddd..8f38ccc2 100644
--- a/dw/textblock.hh
+++ b/dw/textblock.hh
@@ -747,6 +747,7 @@ protected:
    void sizeRequestImpl (core::Requisition *requisition);
    void getExtremesImpl (core::Extremes *extremes);
    void sizeAllocateImpl (core::Allocation *allocation);
+   bool usesAvailWidth ();
    void resizeDrawImpl ();
 
    void markSizeChange (int ref);
diff --git a/dw/widget.cc b/dw/widget.cc
index c649be55..40f690d1 100644
--- a/dw/widget.cc
+++ b/dw/widget.cc
@@ -286,11 +286,6 @@ void Widget::actualQueueResize (int ref, bool extremesChanged, bool fast)
    DBG_OBJ_MSG_END ();
 }
 
-bool Widget::affectedByContainerSizeChange ()
-{
-   return true;
-}
-
 void Widget::containerSizeChanged ()
 {
    DBG_OBJ_MSG ("resize", 0, "<b>containerSizeChanged</b> ()");
@@ -317,6 +312,75 @@ void Widget::containerSizeChanged ()
    DBG_OBJ_MSG_END ();
 }
 
+bool Widget::affectedByContainerSizeChange ()
+{
+   DBG_OBJ_MSG ("resize", 0, "<b>affectedByContainerSizeChange</b> ()");
+   DBG_OBJ_MSG_START ();
+
+   bool ret;
+
+   // This standard implementation is suitable for all widgets which
+   // call correctRequisition() and correctExtremes(), even in the way
+   // how Textblock and Image do (see comments there). Has to be kept
+   // in sync.
+
+   if (container == NULL) {
+      if (style::isAbsLength (getStyle()->width) &&
+          style::isAbsLength (getStyle()->height))
+         // Both absolute, i. e. fixed: no dependency.
+         ret = false;
+      else if (style::isPerLength (getStyle()->width) ||
+               style::isPerLength (getStyle()->height)) {
+         // Any percentage: certainly dependenant.
+         ret = true;
+      } else
+         // One or both is "auto": depends ...
+         ret =
+            (getStyle()->width == style::LENGTH_AUTO ?
+             usesAvailWidth () : false) ||
+            (getStyle()->height == style::LENGTH_AUTO ?
+             usesAvailHeight () : false);
+   } else
+      ret = this->affectsSizeChangeContainerChild (this);
+
+   DBG_OBJ_MSGF ("resize", 1, "=> %s", ret ? "true" : "false");
+   DBG_OBJ_MSG_END ();
+   return ret;
+}
+
+bool Widget::affectsSizeChangeContainerChild (Widget *child)
+{
+   DBG_OBJ_MSGF ("resize", 0, "<b>affectsSizeChangeContainerChild</b> (%p)",
+                 child);
+   DBG_OBJ_MSG_START ();
+
+   bool ret;
+
+   // From the point of view of the container. This standard
+   // implementation should be suitable for most (if not all)
+   // containers.
+
+   if (style::isAbsLength (child->getStyle()->width) &&
+       style::isAbsLength (child->getStyle()->height))
+      // Both absolute, i. e. fixed: no dependency.
+      ret = false;
+   else if (style::isPerLength (child->getStyle()->width) ||
+            style::isPerLength (child->getStyle()->height)) {
+      // Any percentage: certainly dependenant.
+      ret = true;
+   } else
+      // One or both is "auto": depends ...
+      ret =
+         (child->getStyle()->width == style::LENGTH_AUTO ?
+          child->usesAvailWidth () : false) ||
+         (child->getStyle()->height == style::LENGTH_AUTO ?
+          child->usesAvailHeight () : false);
+
+   DBG_OBJ_MSGF ("resize", 1, "=> %s", ret ? "true" : "false");
+   DBG_OBJ_MSG_END ();
+   return ret;  
+}
+
 void Widget::containerSizeChangedForChildren ()
 {
    DBG_OBJ_MSG ("resize", 0, "<b>containerSizeChangedForChildren</b> ()");
@@ -334,6 +398,24 @@ void Widget::containerSizeChangedForChildren ()
 }
 
 /**
+ * \brief Must be implemengted by a method returning true, when
+ *    getAvailWidth() is called.
+ */
+bool Widget::usesAvailWidth ()
+{
+   return false;
+}
+
+/**
+ * \brief Must be implemengted by a method returning true, when
+ *    getAvailHeight() is called.
+ */
+bool Widget::usesAvailHeight ()
+{
+   return false;
+}
+
+/**
  *  \brief This method is a wrapper for Widget::sizeRequestImpl(); it calls
  *     the latter only when needed.
  */
diff --git a/dw/widget.hh b/dw/widget.hh
index 25a951d4..2e51e32c 100644
--- a/dw/widget.hh
+++ b/dw/widget.hh
@@ -171,7 +171,6 @@ private:
    { queueResize (ref, extremesChanged, true); }
    void actualQueueResize (int ref, bool extremesChanged, bool fast);
 
-   bool affectedByContainerSizeChange ();
    void containerSizeChanged ();
 
 public:
@@ -329,6 +328,11 @@ protected:
 
    virtual void containerSizeChangedForChildren ();
 
+   virtual bool affectedByContainerSizeChange ();
+   virtual bool affectsSizeChangeContainerChild (Widget *child);
+   virtual bool usesAvailWidth ();
+   virtual bool usesAvailHeight ();
+
    virtual void notifySetAsTopLevel();
    virtual void notifySetParent();