Commits on Nov 21, 2024

1. [Gtk3] fix for SWTException on Table.remove(...) with focused row ecl… …

   …ipse-platform#1606
   
   Fix for `SWTException` on `Table.remove(...)` with a focused row.
   Cause: `gtk_list_store_remove(...)` for a focused row invokes `Table.cellDataProc(...)` with not-yet-updated `Table.items`.
   Fix: remove `TableItem` from `Table.items` before `gtk_list_store_remove(...)`.
   
   Fixes eclipse-platform#1606
   
   This bug happens in Gtk3.
   I haven't tried to reproduce this bug in GTK4.
   
   Java stacktrace:
   ```java
   org.eclipse.swt.SWTException: Widget is disposed
   	at org.eclipse.swt.SWT.error(SWT.java:4922)
   	at org.eclipse.swt.SWT.error(SWT.java:4837)
   	at org.eclipse.swt.SWT.error(SWT.java:4808)
   	at org.eclipse.swt.widgets.Widget.error(Widget.java:597)
   	at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:512)
   	at org.eclipse.swt.widgets.TableItem.setText(TableItem.java:1363)
   	at org.eclipse.swt.tests.gtk.Test_Gtk3_Table_Remove_Focused_Row.lambda$3(Test_Gtk3_Table_Remove_Focused_Row.java:68)
   	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:91)
   	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:5857)
   	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1617)
   	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1643)
   	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1626)
   	at org.eclipse.swt.widgets.Table.checkData(Table.java:289)
   	at org.eclipse.swt.widgets.Table.cellDataProc(Table.java:227)
   	at org.eclipse.swt.widgets.Display.cellDataProc(Display.java:995)
   	at org.eclipse.swt.internal.gtk.GTK.gtk_list_store_remove(Native Method)
   	at org.eclipse.swt.widgets.Table.remove(Table.java:2668)
   	...
   ```
   
   The main cause of the error is that:
    1. when a row with focus is deleted with `gtk_list_store_remove(...)`, then cell data function `Table.cellDataProc(...)` is called for a row after the removed one
    2. but inside `Table.cellDataProc(...)` `Table.items` isn't yet updated , therefore `Table.cellDataProc(...)` operates with `TableItem`, which is already disposed but not yet removed from `Table.items`
   
   Inside `gtk_list_store_remove(...)` the row is removed from the `GtkTreeModel`, and only then `GtkTreeView` callbacks are invoked.
   It means that when `Table.cellDataProc(...)` is invoked, the row has already been removed in Gtk3.
   
   The fix: remove `TableItem` from `Table.items` before `gtk_list_store_remove(...)` instead of after.
   
   Os:  Ubuntu 24.04.1 LTS
   Gtk: 3.24.41
   Swt: 4.967.8
   
   =================================================
   
   Why `gtk_list_store_remove(...)` invokes `Table.cellDataProc(...)` only for a row with focus and not for ordinary rows?
   
   The reason is that in gtk3 when a row with focus is deleted, the next row receives focus, which among other things creates `GtkCellAccessible` (a "cell with focus" for assistive technology in gtk3).
   Creation of `GtkCellAccessible` invokes cell data function `Table.cellDataProc(...)` - just like it happens when a standard cell in `GtkTreeView` gets rendered.
   
   Here is the stacktrace in gtk3 code:
   ```c
   apply_cell_attributes() at gtkcellarea.c:1257
   g_hash_table_foreach() at ghash.c:2117
   gtk_cell_area_real_apply_attributes() at gtkcellarea.c:1286
   gtk_cell_area_box_apply_attributes() at gtkcellareabox.c:1310
   _gtk_marshal_VOID__OBJECT_BOXED_BOOLEAN_BOOLEANv() at gtkmarshalers.c:5447
   g_type_class_meta_marshalv() at gclosure.c:1062
   _g_closure_invoke_va() at gclosure.c:897
   signal_emit_valist_unlocked() at gsignal.c:3424
   g_signal_emit_valist() at gsignal.c:3263
   g_signal_emit() at gsignal.c:3583
   gtk_cell_area_apply_attributes() at gtkcellarea.c:2373
   gtk_tree_view_column_cell_set_cell_data() at gtktreeviewcolumn.c:2821
   set_cell_data() at gtktreeviewaccessible.c:347
   create_cell() at gtktreeviewaccessible.c:439
   _gtk_tree_view_accessible_add_state() at gtktreeviewaccessible.c:2053
   gtk_tree_view_real_set_cursor() at gtktreeview.c:13377
   gtk_tree_view_row_deleted() at gtktreeview.c:9430
   g_cclosure_marshal_VOID__BOXED() at gmarshal.c:1628
   g_closure_invoke() at gclosure.c:834
   signal_emit_unlocked_R() at gsignal.c:3888
   signal_emit_valist_unlocked() at gsignal.c:3520
   g_signal_emit_valist() at gsignal.c:3263
   g_signal_emit() at gsignal.c:3583
   gtk_tree_model_row_deleted() at gtktreemodel.c:1914
   gtk_list_store_remove() at gtkliststore.c:1219
   Java_org_eclipse_swt_internal_gtk_GTK_gtk_1list_1store_1remove()
   ```
   
   The code that leads to execution of cell data function for a row with focus is in gtktreeview.c:
   ```
   static void
   gtk_tree_view_row_deleted (GtkTreeModel *model,
   			   GtkTreePath  *path,
   			   gpointer      data)
   {
     ...
     /* If the cursor row got deleted, move the cursor to the next row */
     if (tree_view->priv->cursor_node &&
         (tree_view->priv->cursor_node == node ||
          (node->children && (tree_view->priv->cursor_tree == node->children ||
                              _gtk_rbtree_contains (node->children, tree_view->priv->cursor_tree)))))
       {
         ...
         cursor_changed = TRUE;
       }
     ...
     if (cursor_changed)
       {
         if (cursor_node)
           {
             ...
             gtk_tree_view_real_set_cursor (tree_view, cursor_path, CLEAR_AND_SELECT | CURSOR_INVALID);
             ...
           }
         ...
       }
     ...
   }
   ```

   

   om-11-2024 committed Nov 21, 2024
   Configuration menu

   • View commit details
   • Copy full SHA for b48723f
   • Browse repository at this point

   Copy the full SHA

   b48723f View commit details

   Browse the repository at this point in the history