Add:gui_internal:Navigating menus with rotary encoder

Allow navigating the menus of the internal GUI with only PgUp/PgDown
keys, instead of using arrow and Enter keys (which remains supported).
This allows to operate the menus with a rotary encoder, if its two
actions are mapped to PgUp/PgDown.

2 files changed, 164 insertions, 45 deletions

diff --git a/navit/gui/internal/gui_internal.c b/navit/gui/internal/gui_internal.c
index 2fd734f8f..a043b13b4 100644
--- a/navit/gui/internal/gui_internal.c
+++ b/navit/gui/internal/gui_internal.c
@@ -1621,7 +1621,16 @@ gui_internal_cmd_bookmarks(struct gui_priv *this, struct widget *wm, void *data)
 
 
 static void
-gui_internal_keynav_highlight_next(struct gui_priv *this, int dx, int dy);
+gui_internal_keynav_highlight_next(struct gui_priv *this, int dx, int dy, int rotary);
+
+int
+gui_internal_keynav_find_next(struct widget *wi, struct widget *cur, struct widget **result);
+
+int
+gui_internal_keynav_find_prev(struct widget *wi, struct widget *cur, struct widget **result, struct widget** last);
+
+struct widget*
+gui_internal_keynav_find_next_sensitive_child(struct widget *wi);
 
 void
 gui_internal_keypress_do(struct gui_priv *this, char *key)
@@ -2685,6 +2694,71 @@ gui_internal_keynav_point(struct widget *w, int dx, int dy, struct point *p)
 		p->y=w->p.y+w->h;
 }
 
+struct widget*
+gui_internal_keynav_find_next_sensitive_child(struct widget *wi) {
+	GList *l=wi->children;
+	if (wi && wi->state & STATE_SENSITIVE)
+		 return wi;
+	while (l) {
+		struct widget* tmp = gui_internal_keynav_find_next_sensitive_child(l->data);
+		if (tmp)
+			return tmp;
+		l=g_list_next(l);
+	}
+	return NULL;
+}
+
+int
+gui_internal_keynav_find_next(struct widget *wi, struct widget *cur, struct widget **result) {
+	GList *l=wi->children;
+	if (wi == cur)
+	    return 1;
+	while (l) {
+		struct widget *child=l->data;
+		l=g_list_next(l);
+		if (gui_internal_keynav_find_next(child, cur, result)) {
+			while (l) {
+				struct widget *new = gui_internal_keynav_find_next_sensitive_child(l->data);
+				if (new) {
+					*result = new;
+					/* Found one! */
+					return 0;
+				}
+				l=g_list_next(l);
+			}
+			/* Try parent */
+			return 1;
+		}
+	}
+	return 0;
+}
+
+int
+gui_internal_keynav_find_prev(struct widget *wi, struct widget *cur, struct widget **result, struct widget** last) {
+	GList *l=wi->children;
+	struct widget* my_last = NULL;
+	if (last == NULL)
+		last = &my_last;
+	if (wi == cur)
+		return 1;
+	while (l) {
+		struct widget *child=l->data;
+		if (gui_internal_keynav_find_prev(child, cur, result, last)) {
+			*result = *last;
+			if (*last)
+				/* Done. */
+				return 0;
+			else
+				/* Try parent. */
+				return 1;
+		}
+		if (child->state & STATE_SENSITIVE)
+			*last = child;
+		l=g_list_next(l);
+	}
+	return 0;
+}
+
 static void
 gui_internal_keynav_find_closest(struct widget *wi, struct point *p, int dx, int dy, int *distance, struct widget **result)
 {
@@ -2728,13 +2802,16 @@ gui_internal_keynav_find_closest(struct widget *wi, struct point *p, int dx, int
 }
 
 static void
-gui_internal_keynav_highlight_next(struct gui_priv *this, int dx, int dy)
+gui_internal_keynav_highlight_next(struct gui_priv *this, int dx, int dy, int rotary)
 {
 	struct widget *result,*menu=g_list_last(this->root.children)->data;
+	struct widget *cur = NULL;
 	struct point p;
 	int distance;
-	if (this->highlighted && this->highlighted_menu == g_list_last(this->root.children)->data)
+	if (this->highlighted && this->highlighted_menu == g_list_last(this->root.children)->data) {
 		gui_internal_keynav_point(this->highlighted, dx, dy, &p);
+		cur = this->highlighted;
+	}
 	else {
 		p.x=0;
 		p.y=0;
@@ -2744,17 +2821,27 @@ gui_internal_keynav_highlight_next(struct gui_priv *this, int dx, int dy)
 		if (result) {
 			gui_internal_keynav_point(result, dx, dy, &p);
 			dbg(lvl_debug,"result origin=%p p=%d,%d\n", result, p.x, p.y);
+			cur = result;
 		}
 	}
 	result=NULL;
 	distance=INT_MAX;
-	gui_internal_keynav_find_closest(menu, &p, dx, dy, &distance, &result);
+	if (rotary && dx > 0)
+		gui_internal_keynav_find_next(menu, cur, &result);
+	else if (rotary && dx < 0)
+		gui_internal_keynav_find_prev(menu, cur, &result, NULL);
+	else
+		gui_internal_keynav_find_closest(menu, &p, dx, dy, &distance, &result);
 	dbg(lvl_debug,"result=%p\n", result);
 	if (! result) {
-		if (dx < 0)
+		if (dx < 0) {
 			p.x=this->root.w;
-		if (dx > 0)
+			if (rotary) p.y = this->root.h;
+		}
+		if (dx > 0) {
 			p.x=0;
+			if (rotary) p.y = 0;
+		}
 		if (dy < 0)
 			p.y=this->root.h;
 		if (dy > 0)
@@ -2818,17 +2905,23 @@ static void gui_internal_keypress(void *data, char *key)
 	}
 	graphics_draw_mode(this->gra, draw_mode_begin);
 	switch (*key) {
+	case NAVIT_KEY_PAGE_DOWN:
+		gui_internal_keynav_highlight_next(this,1,0,1);
+		break;
+	case NAVIT_KEY_PAGE_UP:
+		gui_internal_keynav_highlight_next(this,-1,0,1);
+		break;
 	case NAVIT_KEY_LEFT:
-		gui_internal_keynav_highlight_next(this,-1,0);
+		gui_internal_keynav_highlight_next(this,-1,0,0);
 		break;
 	case NAVIT_KEY_RIGHT:
-		gui_internal_keynav_highlight_next(this,1,0);
+		gui_internal_keynav_highlight_next(this,1,0,0);
 		break;
 	case NAVIT_KEY_UP:
-		gui_internal_keynav_highlight_next(this,0,-1);
+		gui_internal_keynav_highlight_next(this,0,-1,0);
 		break;
 	case NAVIT_KEY_DOWN:
-		gui_internal_keynav_highlight_next(this,0,1);
+		gui_internal_keynav_highlight_next(this,0,1,0);
 		break;
 	case NAVIT_KEY_BACK:
 		if (g_list_length(this->root.children) > 1)
diff --git a/navit/gui/internal/gui_internal_widget.c b/navit/gui/internal/gui_internal_widget.c
index 7f22f6e24..ab4c51201 100644
--- a/navit/gui/internal/gui_internal_widget.c
+++ b/navit/gui/internal/gui_internal_widget.c
@@ -1261,6 +1261,28 @@ gui_internal_table_render(struct gui_priv * this, struct widget * w)
 	} else {
 		table_data->top_row=NULL;
 	}
+
+	/* First, let's deactivate all columns that are in rows which are *before*
+	 * our current page.
+	 * */
+	GList *row = w->children;
+	while (row != cur_row) {
+		struct widget * cur_row_widget = (struct widget*)row->data;
+		GList * cur_column=NULL;
+		if(cur_row_widget == table_data->scroll_buttons.button_box)
+		{
+			row = g_list_next(row);
+			continue;
+		}
+		for(cur_column = cur_row_widget->children; cur_column;
+		    cur_column=g_list_next(cur_column))
+		{
+			struct  widget * cur_widget = (struct widget*) cur_column->data;
+			cur_widget->state &= ~STATE_SENSITIVE;
+		}
+		row = g_list_next(row);
+	}
+
 	/*
 	 * Loop through each row.  Drawing each cell with the proper sizes,
 	 * at the proper positions.
@@ -1273,7 +1295,7 @@ gui_internal_table_render(struct gui_priv * this, struct widget * w)
 		current_desc = column_desc;
 		cur_row_widget = (struct widget*)cur_row->data;
 		x =w->p.x+this->spacing;
-		if(cur_row_widget == table_data->scroll_buttons.button_box )
+		if(cur_row_widget == table_data->scroll_buttons.button_box)
 		{
 			continue;
 		}
@@ -1288,7 +1310,6 @@ gui_internal_table_render(struct gui_priv * this, struct widget * w)
 			 * No more drawing space left.
 			 */
 			is_skipped=1;
-			break;
 		}
 		for(cur_column = cur_row_widget->children; cur_column;
 		    cur_column=g_list_next(cur_column))
@@ -1296,35 +1317,48 @@ gui_internal_table_render(struct gui_priv * this, struct widget * w)
 			struct  widget * cur_widget = (struct widget*) cur_column->data;
 			dim = (struct table_column_desc*)current_desc->data;
 
-			cur_widget->p.x=x;
-			cur_widget->w=dim->width;
-			cur_widget->p.y=y;
-			cur_widget->h=dim->height;
-			x=x+cur_widget->w;
-			max_height = dim->height;
-			/* We pack the widget before rendering to ensure that the x and y
-			 * coordinates get pushed down.
-			 */
-			gui_internal_widget_pack(this,cur_widget);
-			gui_internal_widget_render(this,cur_widget);
-
-			if(dim->height > max_height)
-			{
+			if (!is_skipped) {
+				cur_widget->p.x=x;
+				cur_widget->w=dim->width;
+				cur_widget->p.y=y;
+				cur_widget->h=dim->height;
+				x=x+cur_widget->w;
 				max_height = dim->height;
+				/* We pack the widget before rendering to ensure that the x and y
+				 * coordinates get pushed down.
+				 */
+				cur_widget->state |= STATE_SENSITIVE;
+				gui_internal_widget_pack(this,cur_widget);
+				gui_internal_widget_render(this,cur_widget);
+
+				if(dim->height > max_height)
+				{
+				    max_height = dim->height;
+				}
+			} else {
+				/* Deactivate contents that we don't have space for. */
+				cur_widget->state &= ~STATE_SENSITIVE;
 			}
 		}
-		
-		/* Row object should have its coordinates in actual
-		 * state to be able to pass mouse clicks to Column objects
-		 */
-		cur_row_widget->p.x=w->p.x;
-		cur_row_widget->w=w->w;
-		cur_row_widget->p.y=y;
-		cur_row_widget->h=max_height;
-		y = y + max_height;
-		table_data->bottom_row=cur_row;
-		current_desc = g_list_next(current_desc);
+
+		if (!is_skipped) {
+			/* Row object should have its coordinates in actual
+			 * state to be able to pass mouse clicks to Column objects
+			 */
+			cur_row_widget->p.x=w->p.x;
+			cur_row_widget->w=w->w;
+			cur_row_widget->p.y=y;
+			cur_row_widget->h=max_height;
+			y = y + max_height;
+			table_data->bottom_row=cur_row;
+			current_desc = g_list_next(current_desc);
+		}
 	}
+
+	/* By default, hide all scroll buttons. */
+	table_data->scroll_buttons.next_button->state&= ~STATE_SENSITIVE;
+	table_data->scroll_buttons.prev_button->state&= ~STATE_SENSITIVE;
+
 	if(table_data->scroll_buttons.button_box && (is_skipped || !is_first_page) && !table_data->scroll_buttons.button_box_hide )
 	{
 		table_data->scroll_buttons.button_box->p.y =w->p.y+w->h-table_data->scroll_buttons.button_box->h -
@@ -1350,19 +1384,11 @@ gui_internal_table_render(struct gui_priv * this, struct widget * w)
 	        {
 			table_data->scroll_buttons.next_button->state|= STATE_SENSITIVE;
 		}
-		else
-		{
-			table_data->scroll_buttons.next_button->state&= ~STATE_SENSITIVE;
-		}
 
 		if(table_data->top_row != w->children)
 		{
 			table_data->scroll_buttons.prev_button->state|= STATE_SENSITIVE;
 		}
-		else
-		{
-			table_data->scroll_buttons.prev_button->state&= ~STATE_SENSITIVE;
-		}
 		gui_internal_widget_render(this,table_data->scroll_buttons.button_box);
 	}