Changeset dbb42c9 in mainline for uspace/lib/ui/src/entry.c

Timestamp:

2021-08-01T14:47:33Z (3 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

1e242121

Parents:

5de71df

Message:

Scroll entry text when it is long

Whew! This is so much harder than it looks!

File:

• uspace/lib/ui/src/entry.c (modified) (14 diffs)

uspace/lib/ui/src/entry.c

@@ -67 +67 @@
         ui_entry_cursor_width = 2,
         ui_entry_sel_hpad = 0,
-        ui_entry_sel_vpad = 2
+        ui_entry_sel_vpad = 2,
+        /** Additional amount to scroll to the left after revealing cursor */
+        ui_entry_left_scroll_margin = 30
 };
 
@@ -156 +158 @@
 {
         entry->halign = halign;
+        ui_entry_scroll_update(entry, true);
+        ui_entry_paint(entry);
 }
 
@@ -186 +190 @@
         entry->pos = str_size(text);
         entry->sel_start = entry->pos;
+        ui_entry_scroll_update(entry, false);
+        ui_entry_paint(entry);
 
         return EOK;
@@ -452 +458 @@
         entry->pos = off1;
         entry->sel_start = off1;
+        ui_entry_scroll_update(entry, false);
         ui_entry_paint(entry);
 }
@@ -494 +501 @@
 
         entry->sel_start = entry->pos;
+        ui_entry_scroll_update(entry, false);
         ui_entry_paint(entry);
 
@@ -526 +534 @@
         entry->sel_start = off;
 
+        ui_entry_scroll_update(entry, false);
         ui_entry_paint(entry);
 }
@@ -551 +560 @@
             str_size(entry->text + off) + 1);
 
+        ui_entry_scroll_update(entry, false);
         ui_entry_paint(entry);
 }
@@ -875 +885 @@
         gfx_coord_t hpad;
         gfx_coord_t vpad;
-        gfx_coord_t width;
         ui_resource_t *res;
 
@@ -895 +904 @@
         }
 
-        width = gfx_text_width(res->font, entry->text);
+        geom->text_rect.p0.x = geom->interior_rect.p0.x + hpad;
+        geom->text_rect.p0.y = geom->interior_rect.p0.y + vpad;
+        geom->text_rect.p1.x = geom->interior_rect.p1.x - hpad;
+        geom->text_rect.p1.y = geom->interior_rect.p1.y - vpad;
+
+        geom->text_pos.x = geom->interior_rect.p0.x + hpad +
+            entry->scroll_pos;
+        geom->text_pos.y = geom->interior_rect.p0.y + vpad;
 
         switch (entry->halign) {
         case gfx_halign_left:
         case gfx_halign_justify:
-                geom->text_pos.x = geom->interior_rect.p0.x + hpad;
+                geom->anchor_x = geom->text_rect.p0.x;
                 break;
         case gfx_halign_center:
-                geom->text_pos.x = (geom->interior_rect.p0.x +
-                    geom->interior_rect.p1.x) / 2 - width / 2;
+                geom->anchor_x = (geom->text_rect.p0.x +
+                    geom->text_rect.p1.x) / 2;
                 break;
         case gfx_halign_right:
-                geom->text_pos.x = geom->interior_rect.p1.x - hpad - 1 - width;
-                break;
-        }
-
-        geom->text_pos.y = geom->interior_rect.p0.y + vpad;
+                geom->anchor_x = geom->text_rect.p1.x;
+                break;
+        }
 }
 
@@ -945 +959 @@
         if (!shift)
                 entry->sel_start = entry->pos;
+
+        ui_entry_scroll_update(entry, false);
         (void) ui_entry_paint(entry);
 }
@@ -959 +975 @@
         if (!shift)
                 entry->sel_start = entry->pos;
+
+        ui_entry_scroll_update(entry, false);
         (void) ui_entry_paint(entry);
 }
@@ -978 +996 @@
         if (!shift)
                 entry->sel_start = entry->pos;
+
+        ui_entry_scroll_update(entry, false);
         (void) ui_entry_paint(entry);
 }
@@ -997 +1017 @@
         if (!shift)
                 entry->sel_start = entry->pos;
+
+        ui_entry_scroll_update(entry, false);
         (void) ui_entry_paint(entry);
 }
@@ -1021 +1043 @@
 }
 
+/** Update text entry scroll position.
+ *
+ * @param entry Text entry
+ * @param realign @c true iff we should left-align short text.
+ *                This should be only used when changing text alignment,
+ *                because left-aligned text entries should not realign
+ *                the text to the left side under normal circumstances.
+ */
+void ui_entry_scroll_update(ui_entry_t *entry, bool realign)
+{
+        ui_entry_geom_t geom;
+        gfx_coord_t x;
+        gfx_coord_t width;
+        gfx_coord2_t tpos;
+        gfx_coord2_t anchor;
+        gfx_text_fmt_t fmt;
+        ui_resource_t *res;
+
+        res = ui_window_get_res(entry->window);
+
+        ui_entry_get_geom(entry, &geom);
+
+        /* Compute position where cursor is currently displayed at */
+        x = geom.text_pos.x + ui_entry_lwidth(entry);
+
+        /* Is cursor off to the left? */
+        if (x < geom.text_rect.p0.x) {
+                /*
+                 * Scroll to make cursor visible and put some space between it
+                 * and the left edge of the text rectangle.
+                 */
+                entry->scroll_pos += geom.text_rect.p0.x - x +
+                    ui_entry_left_scroll_margin;
+
+                /*
+                 * We don't want to scroll further than what's needed
+                 * to reveal the beginning of the text.
+                 */
+                if (entry->scroll_pos > 0)
+                        entry->scroll_pos = 0;
+        }
+
+        /*
+         * Is cursor off to the right? Note that the width of the cursor
+         * is deliberately not taken into account (i.e. we only care
+         * about the left edge of the cursor).
+         */
+        if (x > geom.text_rect.p1.x)
+                entry->scroll_pos -= x + 2 - geom.text_rect.p1.x;
+
+        width = gfx_text_width(res->font, entry->text);
+
+        if (width < geom.text_rect.p1.x - geom.text_rect.p0.x &&
+            (realign || entry->halign != gfx_halign_left)) {
+                /* Text fits inside entry, so we need to align it */
+                anchor.x = geom.anchor_x;
+                anchor.y = 0;
+                gfx_text_fmt_init(&fmt);
+                fmt.halign = entry->halign;
+                gfx_text_start_pos(res->font, &anchor, &fmt, entry->text,
+                    &tpos);
+                entry->scroll_pos = tpos.x - geom.text_rect.p0.x;
+        } else if (geom.text_pos.x + width < geom.text_rect.p1.x &&
+            entry->halign != gfx_halign_left) {
+                /* Text is long, unused space on the right */
+                entry->scroll_pos += geom.text_rect.p1.x -
+                    geom.text_pos.x - width;
+        }
+}
+
 /** @}
  */