Added e-sorter.lo and e-selection-model.lo.

2001-02-27  Christopher James Lahey  <clahey@ximian.com>

	* gal/Makefile.am: Added e-sorter.lo and e-selection-model.lo.

	* gal/util/Makefile.am: Added e-sorter.c and e-sorter.h.

	* gal/util/e-sorter.c, gal/util/e-sorter.h: New class.  This is a
	new simple virtual class for use with ESelectionModel.  It
	implements the same set of methods as ETableSorter but the default
	behavior is as if the sorting was a no-op.

	* gal/widgets/Makefile.am: Added e-selection-model.c and
	e-selection-model.h.

	* gal/widgets/e-selection-model.c,
	gal/widgets/e-selection-model.h: New class.  Implements all of the
	semantics of ETableSelectionModel except for the connection to the
	ETableModel.

svn path=/trunk/; revision=8421

2 files changed, 906 insertions, 0 deletions

diff --git a/widgets/misc/e-selection-model.c b/widgets/misc/e-selection-model.c
new file mode 100644
index 0000000000..e1f558f1e0
--- /dev/null
+++ b/widgets/misc/e-selection-model.c
@@ -0,0 +1,806 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * e-selection-model.c: a Selection Model
+ *
+ * Author:
+ *   Christopher James Lahey <clahey@ximian.com>
+ *
+ * (C) 2000, 2001 Ximian, Inc.
+ */
+#include <config.h>
+#include <gtk/gtksignal.h>
+#include "e-selection-model.h"
+#include "gal/util/e-util.h"
+#include <gdk/gdkkeysyms.h>
+
+#define ESM_CLASS(e) ((ESelectionModelClass *)((GtkObject *)e)->klass)
+
+#define PARENT_TYPE gtk_object_get_type ()
+
+#define ONES ((guint32) 0xffffffff)
+
+#define BOX(n) ((n) / 32)
+#define OFFSET(n) (31 - ((n) % 32))
+#define BITMASK(n) ((guint32)(((guint32) 0x1) << OFFSET((n))))
+#define BITMASK_LEFT(n) ((((n) % 32) == 0) ? 0 : (ONES << (32 - ((n) % 32))))
+#define BITMASK_RIGHT(n) ((guint32)(((guint32) ONES) >> ((n) % 32)))
+
+static GtkObjectClass *e_selection_model_parent_class;
+
+static void esm_select_single_row (ESelectionModel *selection, int row);
+
+enum {
+	CURSOR_CHANGED,
+	CURSOR_ACTIVATED,
+	SELECTION_CHANGED,
+	LAST_SIGNAL
+};
+
+static guint e_selection_model_signals [LAST_SIGNAL] = { 0, };
+
+enum {
+	ARG_0,
+	ARG_SORTER,
+	ARG_CURSOR_ROW,
+	ARG_CURSOR_COL,
+	ARG_SELECTION_MODE,
+	ARG_CURSOR_MODE,
+};
+
+void
+e_selection_model_insert_row(ESelectionModel *esm, int row)
+{
+	int box;
+	int i;
+	if(esm->row_count >= 0) {
+		/* Add another word if needed. */
+		if ((esm->row_count & 0x1f) == 0) {
+			esm->selection = g_renew(gint, esm->selection, (esm->row_count >> 5) + 1);
+			esm->selection[esm->row_count >> 5] = 0;
+		}
+
+		/* The box is the word that our row is in. */
+		box = BOX(row);
+		/* Shift all words to the right of our box right one bit. */
+		for (i = esm->row_count >> 5; i > box; i--) {
+			esm->selection[i] = (esm->selection[i] >> 1) | (esm->selection[i - 1] << 31);
+		}
+
+		/* Shift right half of box one bit to the right. */
+		esm->selection[box] = (esm->selection[box] & BITMASK_LEFT(row)) | ((esm->selection[box] & BITMASK_RIGHT(row)) >> 1);
+		esm->row_count ++;
+	}
+	if (esm->cursor_row >= row)
+		esm->cursor_row ++;
+}
+
+void
+e_selection_model_delete_row(ESelectionModel *esm, int row)
+{
+	int box;
+	int i;
+	int last;
+	int selected = FALSE;
+	if(esm->row_count >= 0) {
+		guint32 bitmask;
+		box = row >> 5;
+		last = esm->row_count >> 5;
+
+		/* Build bitmasks for the left and right half of the box */
+		bitmask = BITMASK_RIGHT(row) >> 1;
+		selected = e_selection_model_is_row_selected(esm, row);
+		/* Shift right half of box one bit to the left. */
+		esm->selection[box] = (esm->selection[box] & BITMASK_LEFT(row))| ((esm->selection[box] & bitmask) << 1);
+
+		/* Shift all words to the right of our box left one bit. */
+		if (box < last) {
+			esm->selection[box] &= esm->selection[box + 1] >> 31;
+
+			for (i = box + 1; i < last; i++) {
+				esm->selection[i] = (esm->selection[i] << 1) | (esm->selection[i + 1] >> 31);
+			}
+			/* this over-runs our memory! */
+			/*esm->selection[i] = esm->selection[i] << 1; */
+		}
+		esm->row_count --;
+		/* Remove the last word if not needed. */
+		if ((esm->row_count & 0x1f) == 0) {
+			esm->selection = g_renew(gint, esm->selection, esm->row_count >> 5);
+		}
+		if (selected && esm->mode == GTK_SELECTION_SINGLE) {
+			esm_select_single_row (esm, row > 0 ? row - 1 : 0);
+		}
+	}
+	if (esm->cursor_row >= row && esm->cursor_row > 0)
+		esm->cursor_row --;
+}
+
+inline static void
+add_sorter(ESelectionModel *esm, ESorter *sorter)
+{
+	esm->sorter = sorter;
+	if (sorter) {
+		gtk_object_ref(GTK_OBJECT(sorter));
+	}
+}
+
+inline static void
+drop_sorter(ESelectionModel *esm)
+{
+	if (esm->sorter) {
+		gtk_object_unref(GTK_OBJECT(esm->sorter));
+	}
+	esm->sorter = NULL;
+}
+
+static void
+esm_destroy (GtkObject *object)
+{
+	ESelectionModel *esm;
+
+	esm = E_SELECTION_MODEL (object);
+
+	drop_sorter(esm);
+
+	g_free(esm->selection);
+}
+
+static void
+esm_get_arg (GtkObject *o, GtkArg *arg, guint arg_id)
+{
+	ESelectionModel *esm = E_SELECTION_MODEL (o);
+
+	switch (arg_id){
+	case ARG_SORTER:
+		GTK_VALUE_OBJECT (*arg) = GTK_OBJECT(esm->sorter);
+		break;
+
+	case ARG_CURSOR_ROW:
+		GTK_VALUE_INT(*arg) = esm->cursor_row;
+		break;
+
+	case ARG_CURSOR_COL:
+		GTK_VALUE_INT(*arg) = esm->cursor_col;
+		break;
+
+	case ARG_SELECTION_MODE:
+		GTK_VALUE_ENUM(*arg) = esm->mode;
+		break;
+
+	case ARG_CURSOR_MODE:
+		GTK_VALUE_ENUM(*arg) = esm->cursor_mode;
+		break;
+	}
+}
+
+static void
+esm_set_arg (GtkObject *o, GtkArg *arg, guint arg_id)
+{
+	ESelectionModel *esm = E_SELECTION_MODEL (o);
+	
+	switch (arg_id){
+	case ARG_SORTER:
+		drop_sorter(esm);
+		add_sorter(esm, GTK_VALUE_OBJECT (*arg) ? E_SORTER(GTK_VALUE_OBJECT (*arg)) : NULL);
+		break;
+
+	case ARG_CURSOR_ROW:
+		e_selection_model_do_something(esm, GTK_VALUE_INT(*arg), esm->cursor_col, 0);
+		break;
+
+	case ARG_CURSOR_COL:
+		e_selection_model_do_something(esm, esm->cursor_row, GTK_VALUE_INT(*arg), 0);
+		break;
+
+	case ARG_SELECTION_MODE:
+		esm->mode = GTK_VALUE_ENUM(*arg);
+		if (esm->mode == GTK_SELECTION_SINGLE) {
+			e_selection_model_do_something(esm, esm->cursor_row, esm->cursor_col, 0);
+		}
+		break;
+
+	case ARG_CURSOR_MODE:
+		esm->cursor_mode = GTK_VALUE_ENUM(*arg);
+		break;
+	}
+}
+
+static void
+e_selection_model_init (ESelectionModel *selection)
+{
+	selection->selection = NULL;
+	selection->row_count = -1;
+	selection->selection_start_row = 0;
+	selection->cursor_row = -1;
+	selection->cursor_col = -1;
+	selection->mode = GTK_SELECTION_MULTIPLE;
+	selection->cursor_mode = E_CURSOR_SIMPLE;
+}
+
+static void
+e_selection_model_class_init (ESelectionModelClass *klass)
+{
+	GtkObjectClass *object_class;
+
+	e_selection_model_parent_class = gtk_type_class (gtk_object_get_type ());
+
+	object_class = GTK_OBJECT_CLASS(klass);
+
+	object_class->destroy = esm_destroy;
+	object_class->get_arg = esm_get_arg;
+	object_class->set_arg = esm_set_arg;
+
+	e_selection_model_signals [CURSOR_CHANGED] =
+		gtk_signal_new ("cursor_changed",
+				GTK_RUN_LAST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (ESelectionModelClass, cursor_changed),
+				gtk_marshal_NONE__INT_INT,
+				GTK_TYPE_NONE, 2, GTK_TYPE_INT, GTK_TYPE_INT);
+
+	e_selection_model_signals [CURSOR_ACTIVATED] =
+		gtk_signal_new ("cursor_activated",
+				GTK_RUN_LAST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (ESelectionModelClass, cursor_activated),
+				gtk_marshal_NONE__INT_INT,
+				GTK_TYPE_NONE, 2, GTK_TYPE_INT, GTK_TYPE_INT);
+
+	e_selection_model_signals [SELECTION_CHANGED] =
+		gtk_signal_new ("selection_changed",
+				GTK_RUN_LAST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (ESelectionModelClass, selection_changed),
+				gtk_marshal_NONE__NONE,
+				GTK_TYPE_NONE, 0);
+
+	klass->cursor_changed    = NULL;
+	klass->cursor_activated  = NULL;
+	klass->selection_changed = NULL;
+
+	gtk_object_class_add_signals (object_class, e_selection_model_signals, LAST_SIGNAL);
+
+	gtk_object_add_arg_type ("ESelectionModel::sorter", GTK_TYPE_OBJECT,
+				 GTK_ARG_READWRITE, ARG_SORTER);
+	gtk_object_add_arg_type ("ESelectionModel::cursor_row", GTK_TYPE_INT,
+				 GTK_ARG_READWRITE, ARG_CURSOR_ROW);
+	gtk_object_add_arg_type ("ESelectionModel::cursor_col", GTK_TYPE_INT,
+				 GTK_ARG_READWRITE, ARG_CURSOR_COL);
+	gtk_object_add_arg_type ("ESelectionModel::selection_mode", GTK_TYPE_ENUM,
+				 GTK_ARG_READWRITE, ARG_SELECTION_MODE);
+	gtk_object_add_arg_type ("ESelectionModel::cursor_mode", GTK_TYPE_ENUM,
+				 GTK_ARG_READWRITE, ARG_CURSOR_MODE);
+}
+
+E_MAKE_TYPE(e_selection_model, "ESelectionModel", ESelectionModel,
+	    e_selection_model_class_init, e_selection_model_init, PARENT_TYPE);
+
+/** 
+ * e_selection_model_is_row_selected
+ * @selection: #ESelectionModel to check
+ * @n: The row to check
+ *
+ * This routine calculates whether the given row is selected.
+ *
+ * Returns: %TRUE if the given row is selected
+ */
+gboolean
+e_selection_model_is_row_selected (ESelectionModel *selection,
+				   gint                 n)
+{
+	if (selection->row_count < n)
+		return 0;
+	else
+		return (selection->selection[BOX(n)] >> OFFSET(n)) & 0x1;
+}
+
+/** 
+ * e_selection_model_foreach
+ * @selection: #ESelectionModel to traverse
+ * @callback: The callback function to call back.
+ * @closure: The closure
+ *
+ * This routine calls the given callback function once for each
+ * selected row, passing closure as the closure.
+ */
+void 
+e_selection_model_foreach     (ESelectionModel *selection,
+			       EForeachFunc callback,
+			       gpointer closure)
+{
+	int i;
+	int last = (selection->row_count + 31) / 32;
+	for (i = 0; i < last; i++) {
+		if (selection->selection[i]) {
+			int j;
+			guint32 value = selection->selection[i];
+			for (j = 0; j < 32; j++) {
+				if (value & 0x80000000) {
+					callback(i * 32 + j, closure);
+				}
+				value <<= 1;
+			}
+		}
+	}
+}
+
+#define OPERATE(object, i,mask,grow) ((grow) ? (((object)->selection[(i)]) |= ((guint32) ~(mask))) : (((object)->selection[(i)]) &= (mask)))
+
+static void
+change_one_row(ESelectionModel *selection, int row, gboolean grow)
+{
+	int i;
+	i = BOX(row);
+
+	OPERATE(selection, i, ~BITMASK(row), grow);
+}
+
+static void
+change_selection(ESelectionModel *selection, int start, int end, gboolean grow)
+{
+	int i, last;
+	if (start != end) {
+		if (selection->sorter && e_sorter_needs_sorting(selection->sorter)) {
+			for ( i = start; i < end; i++) {
+				change_one_row(selection, e_sorter_sorted_to_model(selection->sorter, i), grow);
+			}
+		} else {
+			i = BOX(start);
+			last = BOX(end);
+
+			if (i == last) {
+				OPERATE(selection, i, BITMASK_LEFT(start) | BITMASK_RIGHT(end), grow);
+			} else {
+				OPERATE(selection, i, BITMASK_LEFT(start), grow);
+				if (grow)
+					for (i ++; i < last; i++)
+						selection->selection[i] = ONES;
+				else
+					for (i ++; i < last; i++)
+						selection->selection[i] = 0;
+				OPERATE(selection, i, BITMASK_RIGHT(end), grow);
+			}
+		}
+	}
+}
+
+static void
+esm_select_single_row (ESelectionModel *selection, int row)
+{
+	int i;
+	for (i = 0; i < ((selection->row_count + 31) / 32); i++) {
+		if (!((i == BOX(row) && selection->selection[i] == BITMASK(row)) ||
+		      (i != BOX(row) && selection->selection[i] == 0))) {
+			g_free(selection->selection);
+			selection->selection = g_new0(gint, (selection->row_count + 31) / 32);
+			selection->selection[BOX(row)] = BITMASK(row);
+
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals [SELECTION_CHANGED]);
+			break;
+		}
+	}
+
+	selection->selection_start_row = row;
+}
+
+static void
+esm_toggle_single_row (ESelectionModel *selection, int row)
+{
+	if (selection->selection[BOX(row)] & BITMASK(row))
+		selection->selection[BOX(row)] &= ~BITMASK(row);
+	else
+		selection->selection[BOX(row)] |= BITMASK(row);
+	selection->selection_start_row = row;
+	gtk_signal_emit(GTK_OBJECT(selection),
+			e_selection_model_signals [SELECTION_CHANGED]);
+}
+
+static void
+esm_move_selection_end (ESelectionModel *selection, int row)
+{
+	int old_start;
+	int old_end;
+	int new_start;
+	int new_end;
+	if (selection->sorter && e_sorter_needs_sorting(selection->sorter)) {
+		old_start = MIN (e_sorter_model_to_sorted(selection->sorter, selection->selection_start_row),
+				 e_sorter_model_to_sorted(selection->sorter, selection->cursor_row));
+		old_end = MAX (e_sorter_model_to_sorted(selection->sorter, selection->selection_start_row),
+			       e_sorter_model_to_sorted(selection->sorter, selection->cursor_row)) + 1;
+		new_start = MIN (e_sorter_model_to_sorted(selection->sorter, selection->selection_start_row),
+				 e_sorter_model_to_sorted(selection->sorter, row));
+		new_end = MAX (e_sorter_model_to_sorted(selection->sorter, selection->selection_start_row),
+			       e_sorter_model_to_sorted(selection->sorter, row)) + 1;
+	} else {
+		old_start = MIN (selection->selection_start_row, selection->cursor_row);
+		old_end = MAX (selection->selection_start_row, selection->cursor_row) + 1;
+		new_start = MIN (selection->selection_start_row, row);
+		new_end = MAX (selection->selection_start_row, row) + 1;
+	}
+	/* This wouldn't work nearly so smoothly if one end of the selection weren't held in place. */
+	if (old_start < new_start)
+		change_selection(selection, old_start, new_start, FALSE);
+	if (new_start < old_start)
+		change_selection(selection, new_start, old_start, TRUE);
+	if (old_end < new_end)
+		change_selection(selection, old_end, new_end, TRUE);
+	if (new_end < old_end)
+		change_selection(selection, new_end, old_end, FALSE);
+	gtk_signal_emit(GTK_OBJECT(selection),
+			e_selection_model_signals [SELECTION_CHANGED]);
+}
+
+static void
+esm_set_selection_end (ESelectionModel *selection, int row)
+{
+	esm_select_single_row(selection, selection->selection_start_row);
+	selection->cursor_row = selection->selection_start_row;
+	esm_move_selection_end(selection, row);
+}
+
+/** 
+ * e_selection_model_do_something
+ * @selection: #ESelectionModel to do something to.
+ * @row: The row to do something in.
+ * @col: The col to do something in.
+ * @state: The state in which to do something.
+ *
+ * This routine does whatever is appropriate as if the user clicked
+ * the mouse in the given row and column.
+ */
+void
+e_selection_model_do_something (ESelectionModel *selection,
+				      guint                 row,
+				      guint                 col,
+				      GdkModifierType       state)
+{
+	gint shift_p = state & GDK_SHIFT_MASK;
+	gint ctrl_p = state & GDK_CONTROL_MASK;
+
+	if (row == -1 && col != -1)
+		row = 0;
+	if (col == -1 && row != -1)
+		col = 0;
+
+	if (selection->row_count < 0) {
+		selection->row_count = e_selection_model_get_row_count(selection);
+		if (selection->row_count < 0)
+			return;
+		g_free(selection->selection);
+		selection->selection = g_new0(gint, (selection->row_count + 31) / 32);
+	}
+	if (selection->row_count >= 0 && row < selection->row_count) {
+		switch (selection->mode) {
+		case GTK_SELECTION_SINGLE:
+			esm_select_single_row (selection, row);
+			break;
+		case GTK_SELECTION_BROWSE:
+		case GTK_SELECTION_MULTIPLE:
+		case GTK_SELECTION_EXTENDED:
+			if (shift_p) {
+				esm_set_selection_end (selection, row);
+			} else {
+				if (ctrl_p) {
+					esm_toggle_single_row (selection, row);
+				} else {
+					esm_select_single_row (selection, row);
+				}
+			}
+			break;
+		}
+		if (selection->cursor_row != row ||
+		    selection->cursor_col != col) {
+			selection->cursor_row = row;
+			selection->cursor_col = col;
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_CHANGED], row, col);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], row, col);
+		}
+	}
+}
+
+/** 
+ * e_selection_model_maybe_do_something
+ * @selection: #ESelectionModel to do something to.
+ * @row: The row to do something in.
+ * @col: The col to do something in.
+ * @state: The state in which to do something.
+ *
+ * If this row is selected, this routine just moves the cursor row and
+ * column.  Otherwise, it does the same thing as
+ * e_selection_model_do_something().  This is for being used on
+ * right clicks and other events where if the user hit the selection,
+ * they don't want it to change.
+ */
+void
+e_selection_model_maybe_do_something      (ESelectionModel *selection,
+						 guint                 row,
+						 guint                 col,
+						 GdkModifierType       state)
+{
+	if (e_selection_model_is_row_selected(selection, row)) {
+		selection->cursor_row = row;
+		selection->cursor_col = col;
+	} else {
+		e_selection_model_do_something(selection, row, col, state);
+	}
+}
+
+static gint
+move_selection (ESelectionModel *selection,
+		gboolean              up,
+		GdkModifierType       state)
+{
+	int row = selection->cursor_row;
+	int col = selection->cursor_col;
+	int cursor_activated = TRUE;
+
+	gint shift_p = state & GDK_SHIFT_MASK;
+	gint ctrl_p = state & GDK_CONTROL_MASK;
+
+	row = e_sorter_model_to_sorted(selection->sorter, row);
+	if (up)
+		row--;
+	else
+		row++;
+	if (row < 0)
+		row = 0;
+	if (row >= selection->row_count)
+		row = selection->row_count - 1;
+	row = e_sorter_sorted_to_model(selection->sorter, row);
+
+	switch (selection->mode) {
+	case GTK_SELECTION_BROWSE:
+		if (shift_p) {
+			esm_set_selection_end (selection, row);
+		} else if (!ctrl_p) {
+			esm_select_single_row (selection, row);
+		} else
+			cursor_activated = FALSE;
+		break;
+	case GTK_SELECTION_SINGLE:
+	case GTK_SELECTION_MULTIPLE:
+	case GTK_SELECTION_EXTENDED:
+		esm_select_single_row (selection, row);
+		break;
+	}
+	if (row != -1) {
+		selection->cursor_row = row;
+		gtk_signal_emit(GTK_OBJECT(selection),
+				e_selection_model_signals[CURSOR_CHANGED], row, col);
+		if (cursor_activated)
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], row, col);
+	}
+	return TRUE;
+}
+
+/** 
+ * e_selection_model_key_press
+ * @selection: #ESelectionModel to affect.
+ * @key: The event.
+ *
+ * This routine does whatever is appropriate as if the user pressed
+ * the given key.
+ *
+ * Returns: %TRUE if the #ESelectionModel used the key.
+ */
+gint
+e_selection_model_key_press      (ESelectionModel *selection,
+					GdkEventKey          *key)
+{
+	switch (key->keyval) {
+	case GDK_Up:
+		return move_selection(selection, TRUE, key->state);
+		break;
+	case GDK_Down:
+		return move_selection(selection, FALSE, key->state);
+		break;
+	case GDK_space:
+	case GDK_KP_Space:
+		if (selection->mode != GTK_SELECTION_SINGLE) {
+			esm_toggle_single_row (selection, selection->cursor_row);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], selection->cursor_row, selection->cursor_col);
+			return TRUE;
+		}
+		break;
+	case GDK_Return:
+	case GDK_KP_Enter:
+		if (selection->mode != GTK_SELECTION_SINGLE) {
+			esm_select_single_row (selection, selection->cursor_row);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], selection->cursor_row, selection->cursor_col);
+			return TRUE;
+		}
+		break;
+	case GDK_Home:
+	case GDK_KP_Home:
+		if (selection->cursor_mode == E_CURSOR_LINE) {
+			int row = 0;
+
+			row = e_sorter_sorted_to_model(selection->sorter, row);
+			selection->cursor_row = row;
+
+			esm_select_single_row (selection, selection->cursor_row);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_CHANGED], selection->cursor_row, selection->cursor_col);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], selection->cursor_row, selection->cursor_col);
+			return TRUE;
+		}
+		break;
+	case GDK_End:
+	case GDK_KP_End:
+		if (selection->cursor_mode == E_CURSOR_LINE) {
+			int row = selection->row_count - 1;
+
+			row = e_sorter_sorted_to_model(selection->sorter, row);
+			selection->cursor_row = row;
+
+			esm_select_single_row (selection, selection->cursor_row);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_CHANGED], selection->cursor_row, selection->cursor_col);
+			gtk_signal_emit(GTK_OBJECT(selection),
+					e_selection_model_signals[CURSOR_ACTIVATED], selection->cursor_row, selection->cursor_col);
+			return TRUE;
+		}
+		break;
+	}
+	return FALSE;
+}
+
+/** 
+ * e_selection_model_clear
+ * @selection: #ESelectionModel to clear
+ *
+ * This routine clears the selection to no rows selected.
+ */
+void
+e_selection_model_clear(ESelectionModel *selection)
+{
+	g_free(selection->selection);
+	selection->selection = NULL;
+	selection->row_count = -1;
+	selection->cursor_row = -1;
+	selection->cursor_col = -1;
+	gtk_signal_emit(GTK_OBJECT(selection),
+			e_selection_model_signals [CURSOR_CHANGED], -1, -1);
+	gtk_signal_emit(GTK_OBJECT(selection),
+			e_selection_model_signals [SELECTION_CHANGED]);
+}
+
+#define PART(x,n) (((x) & (0x01010101 << n)) >> n)
+#define SECTION(x, n) (((x) >> (n * 8)) & 0xff)
+
+/** 
+ * e_selection_model_selected_count
+ * @selection: #ESelectionModel to count
+ *
+ * This routine calculates the number of rows selected.
+ *
+ * Returns: The number of rows selected in the given model.
+ */
+gint
+e_selection_model_selected_count (ESelectionModel *selection)
+{
+	gint count;
+	int i;
+	int last;
+
+	if (!selection->selection)
+		return 0;
+
+	count = 0;
+
+	last = BOX(selection->row_count - 1);
+
+	for (i = 0; i <= last; i++) {
+		int j;
+		guint32 thiscount = 0;
+		for (j = 0; j < 8; j++)
+			thiscount += PART(selection->selection[i], j);
+		for (j = 0; j < 4; j++)
+			count += SECTION(thiscount, j);
+	}
+
+	return count;
+}
+
+/** 
+ * e_selection_model_select_all
+ * @selection: #ESelectionModel to select all
+ *
+ * This routine selects all the rows in the given
+ * #ESelectionModel.
+ */
+void
+e_selection_model_select_all (ESelectionModel *selection)
+{
+	int i;
+	
+	if (selection->row_count < 0) {
+		selection->row_count = e_selection_model_get_row_count(selection);
+		if (selection->row_count < 0)
+			return;
+		g_free (selection->selection);
+		selection->selection = g_new0 (gint, (selection->row_count + 31) / 32);
+	}
+	
+	if (!selection->selection)
+		selection->selection = g_new0 (gint, (selection->row_count + 31) / 32);
+	
+	for (i = 0; i < (selection->row_count + 31) / 32; i ++) {
+		selection->selection[i] = ONES;
+	}
+
+	/* need to zero out the bits corresponding to the rows not
+	   selected in the last full 32 bit mask */
+	if (selection->row_count % 32) {
+		int unselected_mask = 0;
+		int num_unselected_in_last_byte = 32 - selection->row_count % 32;
+
+		for (i = 0; i < num_unselected_in_last_byte; i ++)
+			unselected_mask |= 1 << i;
+
+		selection->selection[(selection->row_count + 31) / 32 - 1] &= ~unselected_mask;
+	}
+
+	selection->cursor_col = 0;
+	selection->cursor_row = 0;
+	selection->selection_start_row = 0;
+	gtk_signal_emit (GTK_OBJECT (selection),
+			 e_selection_model_signals [CURSOR_CHANGED], 0, 0);
+	gtk_signal_emit (GTK_OBJECT (selection),
+			 e_selection_model_signals [SELECTION_CHANGED]);
+}
+
+/** 
+ * e_selection_model_invert_selection
+ * @selection: #ESelectionModel to invert
+ *
+ * This routine inverts all the rows in the given
+ * #ESelectionModel.
+ */
+void
+e_selection_model_invert_selection (ESelectionModel *selection)
+{
+	int i;
+	
+	if (selection->row_count < 0) {
+		selection->row_count = e_selection_model_get_row_count (selection);
+		if (selection->row_count < 0)
+			return;
+		g_free (selection->selection);
+		selection->selection = g_new0 (gint, (selection->row_count + 31) / 32);
+	}
+	
+	if (!selection->selection)
+		selection->selection = g_new0 (gint, (selection->row_count + 31) / 32);
+	
+	for (i = 0; i < (selection->row_count + 31) / 32; i ++) {
+		selection->selection[i] = ~selection->selection[i];
+	}
+	
+	selection->cursor_col = -1;
+	selection->cursor_row = -1;
+	selection->selection_start_row = 0;
+	gtk_signal_emit (GTK_OBJECT (selection),
+			 e_selection_model_signals [CURSOR_CHANGED], -1, -1);
+	gtk_signal_emit (GTK_OBJECT (selection),
+			 e_selection_model_signals [SELECTION_CHANGED]);
+}
+
+int
+e_selection_model_get_row_count (ESelectionModel *selection)
+{
+	g_return_val_if_fail(selection != NULL, 0);
+	g_return_val_if_fail(E_IS_SELECTION_MODEL(selection), 0);
+
+	if (ESM_CLASS(selection)->get_row_count)
+		return ESM_CLASS(selection)->get_row_count (selection);
+	else
+		return 0;
+}
diff --git a/widgets/misc/e-selection-model.h b/widgets/misc/e-selection-model.h
new file mode 100644
index 0000000000..564a3e6e50
--- /dev/null
+++ b/widgets/misc/e-selection-model.h
@@ -0,0 +1,100 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+#ifndef _E_SELECTION_MODEL_H_
+#define _E_SELECTION_MODEL_H_
+
+#include <gtk/gtkobject.h>
+#include <gal/util/e-sorter.h>
+#include <gdk/gdktypes.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+#define E_SELECTION_MODEL_TYPE        (e_selection_model_get_type ())
+#define E_SELECTION_MODEL(o)          (GTK_CHECK_CAST ((o), E_SELECTION_MODEL_TYPE, ESelectionModel))
+#define E_SELECTION_MODEL_CLASS(k)    (GTK_CHECK_CLASS_CAST((k), E_SELECTION_MODEL_TYPE, ESelectionModelClass))
+#define E_IS_SELECTION_MODEL(o)       (GTK_CHECK_TYPE ((o), E_SELECTION_MODEL_TYPE))
+#define E_IS_SELECTION_MODEL_CLASS(k) (GTK_CHECK_CLASS_TYPE ((k), E_SELECTION_MODEL_TYPE))
+
+typedef void (*EForeachFunc) (int model_row,
+			      gpointer closure);
+
+/* list selection modes */
+typedef enum {
+	E_CURSOR_LINE,
+	E_CURSOR_SIMPLE,
+	E_CURSOR_SPREADSHEET,
+} ECursorMode;
+
+typedef struct {
+	GtkObject     base;
+
+	ESorter *sorter;
+
+	gint row_count;
+        guint32 *selection;
+
+	gint cursor_row;
+	gint cursor_col;
+	gint selection_start_row;
+
+	guint model_changed_id;
+	guint model_row_inserted_id, model_row_deleted_id;
+
+	guint frozen : 1;
+	guint selection_model_changed : 1;
+	guint group_info_changed : 1;
+
+	GtkSelectionMode mode;
+	ECursorMode cursor_mode;
+} ESelectionModel;
+
+typedef struct {
+	GtkObjectClass parent_class;
+
+	gint (*get_row_count)     (ESelectionModel *selection);
+
+	/*
+	 * Signals
+	 */
+
+	void (*cursor_changed)    (ESelectionModel *selection, int row, int col);
+	void (*cursor_activated)  (ESelectionModel *selection, int row, int col);
+	void (*selection_changed) (ESelectionModel *selection);
+
+} ESelectionModelClass;
+
+GtkType   e_selection_model_get_type            (void);
+gboolean  e_selection_model_is_row_selected     (ESelectionModel *selection,
+						 gint             n);
+void      e_selection_model_foreach             (ESelectionModel *selection,
+						 EForeachFunc     callback,
+						 gpointer         closure);
+void      e_selection_model_do_something        (ESelectionModel *selection,
+						 guint            row,
+						 guint            col,
+						 GdkModifierType  state);
+void      e_selection_model_maybe_do_something  (ESelectionModel *selection,
+						 guint            row,
+						 guint            col,
+						 GdkModifierType  state);
+gint      e_selection_model_key_press           (ESelectionModel *selection,
+						 GdkEventKey     *key);
+void      e_selection_model_clear               (ESelectionModel *selection);
+gint      e_selection_model_selected_count      (ESelectionModel *selection);
+void      e_selection_model_select_all          (ESelectionModel *selection);
+void      e_selection_model_invert_selection    (ESelectionModel *selection);
+void      e_selection_model_insert_row          (ESelectionModel *esm,
+						 int              row);
+void      e_selection_model_delete_row          (ESelectionModel *esm,
+						 int              row);
+
+/* Virtual Function */
+gint      e_selection_model_get_row_count       (ESelectionModel *esm);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+
+#endif /* _E_SELECTION_MODEL_H_ */