ScrollList gadget redraw fixes

When _set_colour() is called, remember to redraw the gadget if the colours changed.
When _set_font() is called, remember to redraw the gadget and try to preserve the scroll bar positions.
Save a couple of SWIs if we know the scroll bars must jump in 2 other places.
Remove ScrollLisS, its (never called) function did nothing but return.
Removed duplicate redraw_box, same as redraw_all_box and marked as const.

Reported by Fred Graute, reference
  https://www.riscosopen.org/forum/forums/4/topics/3628
the memory leak aspects of the report have been transferred to ticket #414 for later consideration.
Tested with !ExifEdit and some special versions from Fred with the redraw workarounds removed.

Version 0.39. Tagged as 'Gadgets-0_39'

Makefile

@@ -19,7 +19,7 @@ COMPONENT     = Gadgets
 TARGET       ?= TextGadget
 OBJS          = glib glib3 main MemMan riscos_uti Scrollbar\
                 ScrollList Sizes TextArea TextMan Font riscos_gra\
-                ScrollLisS TAsel_ven Utils
+                TAsel_ven Utils
 CMHGDEPENDS   = main
 ROMCDEFINES   = -DROM
 CINCLUDES     = -IC:tboxlibint,tbox:,C:

VersionNum

-/* (0.38)
+/* (0.39)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  * Last processed by srccommit version: 1.1.
  *
  */
-#define Module_MajorVersion_CMHG        0.38
+#define Module_MajorVersion_CMHG        0.39
 #define Module_MinorVersion_CMHG        
-#define Module_Date_CMHG                18 Aug 2015
+#define Module_Date_CMHG                12 Oct 2015
 
-#define Module_MajorVersion             "0.38"
-#define Module_Version                  38
+#define Module_MajorVersion             "0.39"
+#define Module_Version                  39
 #define Module_MinorVersion             ""
-#define Module_Date                     "18 Aug 2015"
+#define Module_Date                     "12 Oct 2015"
 
-#define Module_ApplicationDate          "18-Aug-15"
+#define Module_ApplicationDate          "12-Oct-15"
 
 #define Module_ComponentName            "Gadgets"
 #define Module_ComponentPath            "castle/RiscOS/Sources/Toolbox/Gadgets"
 
-#define Module_FullVersion              "0.38"
-#define Module_HelpVersion              "0.38 (18 Aug 2015)"
-#define Module_LibraryVersionInfo       "0:38"
+#define Module_FullVersion              "0.39"
+#define Module_HelpVersion              "0.39 (12 Oct 2015)"
+#define Module_LibraryVersionInfo       "0:39"

c/ScrollList

@@ -72,11 +72,14 @@ static unsigned int vscroll_width = SCROLLBAR_SIZE;
 
 static PrivateScrollList **scrolllist_list = NULL;
 
-// Cannot be a const, 'cos of the stupid blimmin' tbox header files
-static wimp_Bbox		redraw_box = {0, -0xffff, 0xffff, 0};
+static const wimp_Bbox redraw_all_box = {0, -0xffff, 0xffff, 0};
 
 static _kernel_oserror *_make_visible(const PrivateScrollList *sdata,
 			int visible);
+static _kernel_oserror *_scrolllist_redraw(const PrivateScrollList *sdata,
+			WindowRedraw *block, wimp_Bbox *box,
+			unsigned int sprite_width,
+			unsigned int item_height, int base_line);
 
 static const WindowTemplate window_template =
 {
@@ -140,8 +143,6 @@ static /* const */ ObjectTemplateHeader scroll_list_window =
     sizeof(WindowTemplate)	// body_size
 };
 
-static wimp_Bbox redraw_all_box = {0, -0xffff, 0xffff, 0};
-
 _kernel_oserror *scrolllist_init(void)
 {
     scroll_list_window.body = (void*) &window_template;
@@ -548,6 +549,8 @@ _kernel_oserror *scrolllist_remove(PrivateScrollList *handle)
 static _kernel_oserror *_set_colour(PrivateScrollList *handle,
 	unsigned int flags, unsigned int foreground, unsigned int background)
 {
+    BOOL changed;
+
     if (flags | ScrollList_DesktopColours == flags)
     {
         // Need to translate desktop colours to real colours
@@ -560,9 +563,18 @@ static _kernel_oserror *_set_colour(PrivateScrollList *handle,
         foreground = palette.colours[foreground] & ~0xff;
         background = palette.colours[background] & ~0xff;
     }
+    changed = (handle->foreground != foreground) ||
+              (handle->background != background);
     handle->foreground = foreground;
     handle->background = background;
 
+    if (changed)
+    {
+        // Redraw, given colour change
+        _swix(Toolbox_ObjectMiscOp, _INR(0,3),
+              0, handle->object_id, Window_ForceRedraw, &redraw_all_box);
+    }
+
     return NULL;
 }
 
@@ -666,9 +678,12 @@ static _kernel_oserror *_add_item(PrivateScrollList *sdata,
 
     sdata->no_entries++;
 
-    // Remember existing window details
-    window_get_wimp_handle(0, sdata->object_id, &state.open.window_handle);
-    wimp_get_window_state(&state);
+    if (!(flags & ScrollList_AddItem_MakeVisible))
+    {
+        // Remember existing window details
+        window_get_wimp_handle(0, sdata->object_id, &state.open.window_handle);
+        wimp_get_window_state(&state);
+    }
 
     // Update window extent (this scrolls to the top of the display too)
     _show(sdata);
@@ -695,10 +710,9 @@ static _kernel_oserror *_add_item(PrivateScrollList *sdata,
         }
     }
 
-//    scrolllist_update(sdata, sdata->box.xmin, sdata->box.ymin,
-//    		sdata->box.xmax - vscroll_width, sdata->box.ymax);
+    // Redraw, given addition
     _swix(Toolbox_ObjectMiscOp, _INR(0,3),
-          0, sdata->object_id, Window_ForceRedraw, &redraw_box);
+          0, sdata->object_id, Window_ForceRedraw, &redraw_all_box);
 
     return NULL;
 }
@@ -763,10 +777,12 @@ static _kernel_oserror *_delete_items(PrivateScrollList *sdata,
 
     sdata->no_entries -= end - start + 1;
 
-
-    // Remember existing window details
-    window_get_wimp_handle(0, sdata->object_id, &state.open.window_handle);
-    wimp_get_window_state(&state);
+    if (flags & ScrollList_DeleteItems_DoNotJumpToTop)
+    {
+        // Remember existing window details
+        window_get_wimp_handle(0, sdata->object_id, &state.open.window_handle);
+        wimp_get_window_state(&state);
+    }
 
     // Update window extent (this scrolls to the top of the display too)
     _show(sdata);
@@ -785,10 +801,9 @@ static _kernel_oserror *_delete_items(PrivateScrollList *sdata,
         }
     }
 
-//    scrolllist_update(sdata, sdata->box.xmin, sdata->box.ymin,
-//    		sdata->box.xmax - vscroll_width, sdata->box.ymax);
+    // Redraw, given deletion
     _swix(Toolbox_ObjectMiscOp, _INR(0,3),
-          0, sdata->object_id, Window_ForceRedraw, &redraw_box);
+          0, sdata->object_id, Window_ForceRedraw, &redraw_all_box);
 
     if (flags & ScrollList_SelectionChangingMethod_SendEvent)
         return _send_selection_event(sdata, 0, -1);
@@ -911,6 +926,7 @@ static _kernel_oserror *_set_font(PrivateScrollList *sdata,
 				unsigned int width, unsigned int height)
 {
     _kernel_oserror	*e;
+    wimp_GetWindowState	state;
 
     if (sdata->font_handle != 0)
     {
@@ -941,8 +957,30 @@ static _kernel_oserror *_set_font(PrivateScrollList *sdata,
         }
     }
 
-    scrolllist_update(sdata, sdata->box.xmin, sdata->box.ymin,
-    		sdata->box.xmax - vscroll_width, sdata->box.ymax);
+    // Remember existing window details
+    window_get_wimp_handle(0, sdata->object_id, &state.open.window_handle);
+    wimp_get_window_state(&state);
+
+    // Update window extent (this scrolls to the top of the display too)
+    _show(sdata);
+
+    if (1)
+    {
+        int x = state.open.scx, y = state.open.scy;
+
+        // Restore scroll position
+        if (!wimp_get_window_state(&state))
+        {
+            state.open.scx = x;
+            state.open.scy = y;
+
+            wimp_open_window((wimp_OpenWindow *) &state);
+        }
+    }
+
+    // Redraw, given font change
+    _swix(Toolbox_ObjectMiscOp, _INR(0,3),
+          0, sdata->object_id, Window_ForceRedraw, &redraw_all_box);
 
     return NULL;
 }
@@ -1137,8 +1175,6 @@ _kernel_oserror *scrolllist_method(PrivateScrollList *sdata,
         case ScrollList_SetColour:
             // R4 = foreground col, R5 = background col
             e = _set_colour(sdata, regs->r[0], regs->r[4], regs->r[5]);
-            scrolllist_update(sdata, sdata->box.xmin, sdata->box.ymin,
-    		sdata->box.xmax - vscroll_width, sdata->box.ymax);
             break;
 
         case ScrollList_GetColour:
@@ -1255,7 +1291,7 @@ _kernel_oserror *scrolllist_plot(ScrollList *sdata)
     return NULL;
 }
 
-_kernel_oserror *_scrolllist_redraw(const PrivateScrollList *sdata,
+static _kernel_oserror *_scrolllist_redraw(const PrivateScrollList *sdata,
 				WindowRedraw *block, wimp_Bbox *box,
 				unsigned int sprite_width,
 				unsigned int item_height, int base_line)

h/ScrollLisP

@@ -50,17 +50,6 @@ typedef struct {
     unsigned int	visible;
 } PrivateScrollList;
 
-/* Used in ScrollLisS.s */
-_kernel_oserror *_scrolllist_redraw(const PrivateScrollList *sdata,
-				WindowRedraw *block, wimp_Bbox *box,
-				unsigned int max_sprite_width,
-				unsigned int max_height,
-				int base_line);
-
-/* Implemented in ScrollLisS.s */
-_kernel_oserror *scrolllist_update(PrivateScrollList *sdata,
-			int xmin, int ymin, int xmax, int ymax);
-
 /* Others */
 int             scrolllist_active(void);
 _kernel_oserror *scrolllist_init(void);

s/ScrollLisS

-; Copyright 1997 Acorn Computers Ltd
-;
-; Licensed under the Apache License, Version 2.0 (the "License");
-; you may not use this file except in compliance with the License.
-; You may obtain a copy of the License at
-;
-;     http://www.apache.org/licenses/LICENSE-2.0
-;
-; Unless required by applicable law or agreed to in writing, software
-; distributed under the License is distributed on an "AS IS" BASIS,
-; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-; See the License for the specific language governing permissions and
-; limitations under the License.
-;
-; ScrollList assember functions
-
-; History: PW: 09-Aug-96: Created
-
-	AREA    |C$$code|, CODE, READONLY
-
-	GET	hdr:ListOpts
-	GET	hdr:Macros
-        GET     Hdr:System
-        GET     Hdr:APCS.<APCS>
-
-; APCS compliant
-; SVC mode compatible (link register stacked)
-
-; Updates a scrolling list gadget
-; Prototype: _kernel_oserror *scrolllist_update(PrivateScrollList *sdata,
-;			int xmin, int ymin, int xmax, int ymax);
-; On entry:	r0 = sdata
-;		r1 = xmin
-;		r2 = ymin
-;		r3 = xmax
-;		[ip, #0] = ymax
-scrolllist_update
-	EXPORT	scrolllist_update
-
-      [ {TRUE}
-        Return  ,LinkNotStacked
-      |
-	mov	ip, sp
-	stmfd	sp!, {r4, lr}
-
-	ldr	r4, [ip]
-
-	sub	sp, sp, #40
-	stmia	sp, {r1-r4}		; Store redraw coords
-	sub	sp, sp, #4
-
-	ldr	r1, [r0, #12]		; Load window handle
-	str	r1, [sp]		; Store window handle
-
-	mov	r4, r0			; r4 == sdata
-	mov	r1, sp
-	swi	XWimp_UpdateWindow
-        Return  "r4",,VS
-
-redraw_loop
-	teq	r0, #0
-	addeq	sp, sp, #44
-	Return  "r4",,EQ
-
-	mov	r0, r4
-	bl	_scrolllist_redraw
-
-	mov	r1, sp
-	swi	XWimp_GetRectangle
-	b	redraw_loop
-      ]
-
-	END