Add a scrollable indication

Draw a themable indication when an edge of a scrolled window
is hiding some content that can be scrolled in.
This commit is contained in:
Matthias Clasen 2014-12-10 10:00:21 -05:00
parent 45d0a5cc4b
commit b73578f95d
3 changed files with 78 additions and 1 deletions

View File

@ -6057,6 +6057,7 @@ GTK_STYLE_CLASS_TOOLBAR
GTK_STYLE_CLASS_TOOLTIP
GTK_STYLE_CLASS_TOP
GTK_STYLE_CLASS_TROUGH
GTK_STYLE_CLASS_UNDERSHOOT
GTK_STYLE_CLASS_VERTICAL
GTK_STYLE_CLASS_VIEW
GTK_STYLE_CLASS_WARNING

View File

@ -158,6 +158,9 @@
#define INDICATOR_FADE_OUT_DURATION 1000
#define INDICATOR_FADE_OUT_TIME 500
/* Scrolled off indication */
#define UNDERSHOOT_SIZE 20
typedef struct
{
GtkWidget *scrollbar;
@ -1822,6 +1825,66 @@ gtk_scrolled_window_draw_overshoot (GtkScrolledWindow *scrolled_window,
gtk_style_context_restore (context);
}
static void
gtk_scrolled_window_draw_undershoot (GtkScrolledWindow *scrolled_window,
cairo_t *cr)
{
GtkScrolledWindowPrivate *priv = scrolled_window->priv;
GtkWidget *widget = GTK_WIDGET (scrolled_window);
GtkStyleContext *context;
GdkRectangle rect;
GtkAdjustment *adj;
context = gtk_widget_get_style_context (widget);
gtk_scrolled_window_relative_allocation (widget, &rect);
gtk_style_context_save (context);
gtk_style_context_remove_class (context, GTK_STYLE_CLASS_FRAME);
gtk_style_context_add_class (context, GTK_STYLE_CLASS_UNDERSHOOT);
adj = gtk_range_get_adjustment (GTK_RANGE (priv->hscrollbar));
if (gtk_adjustment_get_value (adj) < gtk_adjustment_get_upper (adj) - gtk_adjustment_get_page_size (adj))
{
gtk_style_context_add_class (context, GTK_STYLE_CLASS_RIGHT);
gtk_render_background (context, cr, rect.x + rect.width - UNDERSHOOT_SIZE, rect.y, UNDERSHOOT_SIZE, rect.height);
gtk_render_frame (context, cr, rect.x + rect.width - UNDERSHOOT_SIZE, rect.y, UNDERSHOOT_SIZE, rect.height);
gtk_style_context_remove_class (context, GTK_STYLE_CLASS_RIGHT);
}
if (gtk_adjustment_get_value (adj) > gtk_adjustment_get_lower (adj))
{
gtk_style_context_add_class (context, GTK_STYLE_CLASS_LEFT);
gtk_render_background (context, cr, rect.x, rect.y, UNDERSHOOT_SIZE, rect.height);
gtk_render_frame (context, cr, rect.x, rect.y, UNDERSHOOT_SIZE, rect.height);
gtk_style_context_remove_class (context, GTK_STYLE_CLASS_LEFT);
}
adj = gtk_range_get_adjustment (GTK_RANGE (priv->vscrollbar));
if (gtk_adjustment_get_value (adj) < gtk_adjustment_get_upper (adj) - gtk_adjustment_get_page_size (adj))
{
gtk_style_context_add_class (context, GTK_STYLE_CLASS_BOTTOM);
gtk_render_background (context, cr, rect.x, rect.y + rect.height - UNDERSHOOT_SIZE, rect.width, UNDERSHOOT_SIZE);
gtk_render_frame (context, cr, rect.x, rect.y + rect.height - UNDERSHOOT_SIZE, rect.width, UNDERSHOOT_SIZE);
gtk_style_context_remove_class (context, GTK_STYLE_CLASS_BOTTOM);
}
if (gtk_adjustment_get_value (adj) > gtk_adjustment_get_lower (adj))
{
gtk_style_context_add_class (context, GTK_STYLE_CLASS_TOP);
gtk_render_background (context, cr, rect.x, rect.y, rect.width, UNDERSHOOT_SIZE);
gtk_render_frame (context, cr, rect.x, rect.y, rect.width, UNDERSHOOT_SIZE);
gtk_style_context_remove_class (context, GTK_STYLE_CLASS_TOP);
}
gtk_style_context_restore (context);
}
static gboolean
gtk_scrolled_window_draw (GtkWidget *widget,
cairo_t *cr)
@ -1880,7 +1943,10 @@ gtk_scrolled_window_draw (GtkWidget *widget,
GTK_WIDGET_CLASS (gtk_scrolled_window_parent_class)->draw (widget, cr);
if (gtk_cairo_should_draw_window (cr, gtk_widget_get_window (widget)))
{
gtk_scrolled_window_draw_undershoot (scrolled_window, cr);
gtk_scrolled_window_draw_overshoot (scrolled_window, cr);
}
return FALSE;
}

View File

@ -905,6 +905,16 @@ struct _GtkStyleContextClass
*/
#define GTK_STYLE_CLASS_OVERSHOOT "overshoot"
/*
* GTK_STYLE_CLASS_UNDERSHOOT:
* A CSS class that is added on the visual hints that happen
* where content is 'scrolled off' and can be made visible
* by scrolling.
*
* Since: 3.16
*/
#define GTK_STYLE_CLASS_UNDERSHOOT "undershoot"
/*
* GTK_STYLE_CLASS_PAPER:
* A CSS class that is added to areas that should look like paper.