Allow holding down scroll bar buttons on Haiku when overscrolling

* src/haiku_support.cc (EmacsWindow): Set appropriate pulse
rate.
(class EmacsScrollBar, ValueChanged): Don't send any part events
here.
(MouseDown): Set dragging to a value larger than 1 if the scroll
bar is at the end.
(Pulse): New method.

1 files changed, 38 insertions, 7 deletions

diff --git a/src/haiku_support.cc b/src/haiku_support.cc
index 5ad3c7c794d..b58420fcb99 100644
--- a/src/haiku_support.cc
+++ b/src/haiku_support.cc
@@ -422,6 +422,10 @@ public:
                             B_NORMAL_WINDOW_FEEL, B_NO_SERVER_SIDE_WINDOW_MODIFIERS)
   {
     window_id = current_window_id++;
+
+    /* This pulse rate is used by scroll bars for repeating a button
+       action while a button is held down.  */
+    SetPulseRate (30000);
   }
 
   ~EmacsWindow ()
@@ -1766,10 +1770,35 @@ public:
   }
 
   void
+  Pulse (void)
+  {
+    struct haiku_scroll_bar_part_event rq;
+    BPoint point;
+    uint32 buttons;
+
+    if (!dragging)
+      {
+        SetFlags (Flags () & ~B_PULSE_NEEDED);
+        return;
+      }
+
+    GetMouse (&point, &buttons, false);
+
+    if (ButtonRegionFor (current_part).Contains (point))
+      {
+        rq.scroll_bar = this;
+        rq.window = Window ();
+        rq.part = current_part;
+        haiku_write (SCROLL_BAR_PART_EVENT, &rq);
+      }
+
+    BScrollBar::Pulse ();
+  }
+
+  void
   ValueChanged (float new_value)
   {
     struct haiku_scroll_bar_value_event rq;
-    struct haiku_scroll_bar_part_event part;
 
     new_value = Value ();
 
@@ -1780,11 +1809,7 @@ public:
             if (dragging > 1)
               {
                 SetValue (old_value);
-
-                part.scroll_bar = this;
-                part.window = Window ();
-                part.part = current_part;
-                haiku_write (SCROLL_BAR_PART_EVENT, &part);
+                SetFlags (Flags () | B_PULSE_NEEDED);
               }
             else
               dragging++;
@@ -1924,6 +1949,12 @@ public:
             dragging = 1;
             current_part = HAIKU_SCROLL_BAR_DOWN_BUTTON;
 
+            if (Value () == max_value)
+              {
+                SetFlags (Flags () | B_PULSE_NEEDED);
+                dragging = 2;
+              }
+
             haiku_write (SCROLL_BAR_PART_EVENT, &part);
             goto out;
           }
@@ -1967,7 +1998,7 @@ public:
     rq.window = Window ();
 
     haiku_write (SCROLL_BAR_DRAG_EVENT, &rq);
-    dragging = false;
+    dragging = 0;
 
     BScrollBar::MouseUp (pt);
   }