bugfix: consistent use of 'int' for alpha values (#3187373)

WindowMenuAccessor returned strange alpha values if compiled
with 'g++ -Os'; unholy black magic happens if template<int> faces
functions returning only 'usigned char'.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/FbTk/Container.hh b/src/FbTk/Container.hh
index bd5e3aa..f3d9bac 100644
--- a/src/FbTk/Container.hh
+++ b/src/FbTk/Container.hh
@@ -91,7 +91,7 @@ public:
     bool updateLock() const { return m_update_lock; }
 
     void for_each(std::mem_fun_t<void, FbWindow> function);
-    void setAlpha(unsigned char alpha); // set alpha on all windows
+    void setAlpha(int alpha); // set alpha on all windows
 
     ItemList::iterator begin() { return m_item_list.begin(); }
     ItemList::iterator end() { return m_item_list.end(); }