Avoid scroll flickering with a custom tooltip class (TipWin) & a custom button

  Removed  the  workaround  [1] that added a full UI and viewport
redraw  to  conceal  the  lingering tooltips bug [2]. It produced
annoying  scroll  flickering  when  the  mouse  was in the UI but
outside the viewport (e.g. over the panel).

  This  is more a FLTK bug than anything; the FLTK team's plan is
to fix it in FLTK3, and also extend the tooltips API.

  As  FLTK3 may take long to be released, and porting dillo to it
is  non-trivial (if both events ever come to happen), this custom
solution looks quite reasonable for the present times.

  The  patch  introduces a new CustButton class that uses TipWin,
and  thus the tooltip handling is no longer handled by FLTK. This
patch switches the UI buttons to the new CustButton.


1] http://lists.auriga.wearlab.de/pipermail/dillo-dev/2011-July/008515.html
2] http://lists.auriga.wearlab.de/pipermail/dillo-dev/2011-July/008494.html

1 files changed, 27 insertions, 38 deletions

diff --git a/src/ui.cc b/src/ui.cc
index 5755cf98..6d53251b 100644
--- a/src/ui.cc
+++ b/src/ui.cc
@@ -19,6 +19,7 @@
 #include "msg.h"
 #include "timeout.hh"
 #include "utf8.hh"
+#include "tipwin.hh"
 
 #include <FL/Fl.H>
 #include <FL/Fl_Pixmap.H>
@@ -158,10 +159,10 @@ int CustInput::handle(int e)
 /*
  * Used to handle "paste" within the toolbar's Clear button.
  */
-class CustPasteButton : public CustLightButton {
+class CustPasteButton : public CustButton {
 public:
    CustPasteButton(int x, int y, int w, int h, const char *l=0) :
-      CustLightButton(x,y,w,h,l) {};
+      CustButton(x,y,w,h,l) {};
    int handle(int e);
 };
 
@@ -175,7 +176,7 @@ int CustPasteButton::handle(int e)
          return 1;
       }
    }
-   return CustLightButton::handle(e);
+   return CustButton::handle(e);
 }
 
 //----------------------------------------------------------------------------
@@ -379,13 +380,13 @@ static void bugmeter_cb(Fl_Widget *wid, void *data)
 /*
  * Make a generic navigation button
  */
-Fl_Button *UI::make_button(const char *label, Fl_Image *img, Fl_Image *deimg,
-                           int b_n, int start)
+CustButton *UI::make_button(const char *label, Fl_Image *img, Fl_Image *deimg,
+                            int b_n, int start)
 {
    if (start)
       p_xpos = 0;
 
-   Fl_Button *b = new CustLightButton(p_xpos, 0, bw, bh, (lbl) ? label : NULL);
+   CustButton *b = new CustButton(p_xpos, 0, bw, bh, (lbl) ? label : NULL);
    if (img)
       b->image(img);
    if (deimg)
@@ -413,14 +414,14 @@ void UI::make_toolbar(int tw, int th)
    Bookmarks = make_button("Book", icons->ImgBook, NULL, UI_BOOK);
    Tools = make_button("Tools", icons->ImgTools, NULL, UI_TOOLS);
 
-   Back->tooltip("Previous page");
-   Forw->tooltip("Next page");
-   Home->tooltip("Go to the Home page");
-   Reload->tooltip("Reload");
-   Save->tooltip("Save this page");
-   Stop->tooltip("Stop loading");
-   Bookmarks->tooltip("View bookmarks");
-   Tools->tooltip("Settings");
+   Back->set_tooltip("Previous page");
+   Forw->set_tooltip("Next page");
+   Home->set_tooltip("Go to the Home page");
+   Reload->set_tooltip("Reload");
+   Save->set_tooltip("Save this page");
+   Stop->set_tooltip("Stop loading");
+   Bookmarks->set_tooltip("View bookmarks");
+   Tools->set_tooltip("Settings");
 }
 
 /*
@@ -428,14 +429,14 @@ void UI::make_toolbar(int tw, int th)
  */
 void UI::make_location(int ww)
 {
-   Fl_Button *b;
+   CustButton *b;
 
-    Clear = b = new CustPasteButton(p_xpos,0,16,lh,0);
+    b = Clear = (CustButton*) new CustPasteButton(p_xpos,0,16,lh,0);
     b->image(icons->ImgClear);
     b->callback(clear_cb, this);
     b->clear_visible_focus();
     b->box(FL_THIN_UP_BOX);
-    b->tooltip("Clear the URL box.\nMiddle-click to paste a URL.");
+    b->set_tooltip("Clear the URL box.\nMiddle-click to paste a URL.");
     p_xpos += b->w();
 
     Fl_Input *i = Location = new CustInput(p_xpos,0,ww-p_xpos-32,lh,0);
@@ -445,20 +446,20 @@ void UI::make_location(int ww)
     i->tooltip("Location");
     p_xpos += i->w();
 
-    Search = b = new CustLightButton(p_xpos,0,16,lh,0);
+    Search = b = new CustButton(p_xpos,0,16,lh,0);
     b->image(icons->ImgSearch);
     b->callback(search_cb, this);
     b->clear_visible_focus();
     b->box(FL_THIN_UP_BOX);
-    b->tooltip("Search the Web");
+    b->set_tooltip("Search the Web");
     p_xpos += b->w();
 
-    Help = b = new CustLightButton(p_xpos,0,16,lh,0);
+    Help = b = new CustButton(p_xpos,0,16,lh,0);
     b->image(icons->ImgHelp);
     b->callback(help_cb, this);
     b->clear_visible_focus();
     b->box(FL_THIN_UP_BOX);
-    b->tooltip("Help");
+    b->set_tooltip("Help");
     p_xpos += b->w();
 
 }
@@ -489,10 +490,10 @@ void UI::make_progress_bars(int wide, int thin_up)
  */
 Fl_Widget *UI::make_filemenu_button()
 {
-   Fl_Button *btn;
+   CustButton *btn;
    int w = 0, h = 0, padding;
 
-   FileButton = btn = new Fl_Button(p_xpos,0,bw,bh,"W");
+   FileButton = btn = new CustButton(p_xpos,0,bw,bh,"W");
    btn->labeltype(FL_FREE_LABELTYPE);
    btn->measure_label(w, h);
    padding = w;
@@ -504,7 +505,7 @@ Fl_Widget *UI::make_filemenu_button()
    _MSG("UI::make_filemenu_button w=%d h=%d padding=%d\n", w, h, padding);
    btn->box(FL_THIN_UP_BOX);
    btn->callback(filemenu_cb, this);
-   btn->tooltip("File menu");
+   btn->set_tooltip("File menu");
    btn->clear_visible_focus();
    if (!prefs.show_filemenu)
       btn->hide();
@@ -610,11 +611,11 @@ void UI::make_status_bar(int ww, int wh)
     StatusOutput->color(FL_GRAY_RAMP + 18);
 
     // Bug Meter
-    BugMeter = new CustLightButton(ww-bm_w,wh-sh,bm_w,sh);
+    BugMeter = new CustButton(ww-bm_w,wh-sh,bm_w,sh);
     BugMeter->image(icons->ImgMeterOK);
     BugMeter->box(FL_THIN_DOWN_BOX);
     BugMeter->align(FL_ALIGN_INSIDE | FL_ALIGN_TEXT_NEXT_TO_IMAGE);
-    BugMeter->tooltip("Show HTML bugs\n(right-click for menu)");
+    BugMeter->set_tooltip("Show HTML bugs\n(right-click for menu)");
     BugMeter->callback(bugmeter_cb, this);
     BugMeter->clear_visible_focus();
 
@@ -632,7 +633,6 @@ UI::UI(int x, int y, int ui_w, int ui_h, const char* label, const UI *cur_ui) :
    LocBar = NavBar = StatusBar = NULL;
 
    Tabs = NULL;
-   TabTooltip = NULL;
    TopGroup = this;
    TopGroup->box(FL_NO_BOX);
    clear_flag(SHORTCUT_LABEL);
@@ -691,7 +691,6 @@ UI::UI(int x, int y, int ui_w, int ui_h, const char* label, const UI *cur_ui) :
 UI::~UI()
 {
    _MSG("UI::~UI()\n");
-   dFree(TabTooltip);
 }
 
 /*
@@ -703,16 +702,6 @@ int UI::handle(int event)
 
    int ret = 0;
    if (event == FL_KEYBOARD) {
-      /* WORKAROUND: remove the Panel's fltk-tooltip.
-       * Although the expose event is delivered, it has an offset. This
-       * extra call avoids the lingering tooltip. */
-      if (!Fl::event_inside(Main) &&
-          (Fl::event_inside((Fl_Widget*)tabs()) ||
-           Fl::event_inside(NavBar) ||
-           (LocBar && Fl::event_inside(LocBar)) ||
-           (StatusBar && Fl::event_inside(StatusBar))))
-         window()->damage(FL_DAMAGE_EXPOSE,0,0,1,1);
-
       return 0; // Receive as shortcut
    } else if (event == FL_SHORTCUT) {
       KeysCommand_t cmd = Keys::getKeyCmd();