gtk2/gtk/gtkalignment.c

844 lines
28 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GTK+ Team and others 1997-2000. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
/**
* SECTION:gtkalignment
* @Short_description: A widget which controls the alignment and size of its child
* @Title: GtkAlignment
*
* The #GtkAlignment widget controls the alignment and size of its child widget.
* It has four settings: xscale, yscale, xalign, and yalign.
*
* The scale settings are used to specify how much the child widget should
* expand to fill the space allocated to the #GtkAlignment.
* The values can range from 0 (meaning the child doesn't expand at all) to
* 1 (meaning the child expands to fill all of the available space).
*
* The align settings are used to place the child widget within the available
* area. The values range from 0 (top or left) to 1 (bottom or right).
* Of course, if the scale settings are both set to 1, the alignment settings
* have no effect.
*
* <note>
* <para>
* Note that the desired effect can in most cases be achieved by using the
* #GtkWidget:halign, #GtkWidget:valign and #GtkWidget:margin properties
* on the child widget, so #GtkAlignment should not be used in new code.
* </para>
* </note>
*/
#include "config.h"
#include "gtkalignment.h"
#include "gtksizerequest.h"
#include "gtkprivate.h"
#include "gtkintl.h"
struct _GtkAlignmentPrivate
{
gfloat xalign;
gfloat yalign;
gfloat xscale;
gfloat yscale;
guint padding_bottom;
guint padding_top;
guint padding_left;
guint padding_right;
};
enum {
PROP_0,
PROP_XALIGN,
PROP_YALIGN,
PROP_XSCALE,
PROP_YSCALE,
PROP_TOP_PADDING,
PROP_BOTTOM_PADDING,
PROP_LEFT_PADDING,
PROP_RIGHT_PADDING
};
static void gtk_alignment_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
static void gtk_alignment_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec);
static void gtk_alignment_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec);
static void gtk_alignment_get_preferred_width (GtkWidget *widget,
gint *minimum_size,
gint *natural_size);
static void gtk_alignment_get_preferred_height (GtkWidget *widget,
gint *minimum_size,
gint *natural_size);
static void gtk_alignment_get_preferred_width_for_height (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size);
static void gtk_alignment_get_preferred_height_for_width (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size);
static void gtk_alignment_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size,
gint *minimum_baseline,
gint *natural_baseline);
G_DEFINE_TYPE_WITH_PRIVATE (GtkAlignment, gtk_alignment, GTK_TYPE_BIN)
static void
gtk_alignment_class_init (GtkAlignmentClass *class)
{
GObjectClass *gobject_class;
GtkWidgetClass *widget_class;
gobject_class = (GObjectClass*) class;
widget_class = (GtkWidgetClass*) class;
gobject_class->set_property = gtk_alignment_set_property;
gobject_class->get_property = gtk_alignment_get_property;
widget_class->size_allocate = gtk_alignment_size_allocate;
widget_class->get_preferred_width = gtk_alignment_get_preferred_width;
widget_class->get_preferred_height = gtk_alignment_get_preferred_height;
widget_class->get_preferred_width_for_height = gtk_alignment_get_preferred_width_for_height;
widget_class->get_preferred_height_for_width = gtk_alignment_get_preferred_height_for_width;
widget_class->get_preferred_height_and_baseline_for_width = gtk_alignment_get_preferred_height_and_baseline_for_width;
g_object_class_install_property (gobject_class,
PROP_XALIGN,
g_param_spec_float("xalign",
P_("Horizontal alignment"),
P_("Horizontal position of child in available space. 0.0 is left aligned, 1.0 is right aligned"),
0.0,
1.0,
0.5,
GTK_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_YALIGN,
g_param_spec_float("yalign",
P_("Vertical alignment"),
P_("Vertical position of child in available space. 0.0 is top aligned, 1.0 is bottom aligned"),
0.0,
1.0,
0.5,
GTK_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_XSCALE,
g_param_spec_float("xscale",
P_("Horizontal scale"),
P_("If available horizontal space is bigger than needed for the child, how much of it to use for the child. 0.0 means none, 1.0 means all"),
0.0,
1.0,
1.0,
GTK_PARAM_READWRITE));
g_object_class_install_property (gobject_class,
PROP_YSCALE,
g_param_spec_float("yscale",
P_("Vertical scale"),
P_("If available vertical space is bigger than needed for the child, how much of it to use for the child. 0.0 means none, 1.0 means all"),
0.0,
1.0,
1.0,
GTK_PARAM_READWRITE));
/**
* GtkAlignment:top-padding:
*
* The padding to insert at the top of the widget.
*
* Since: 2.4
*/
g_object_class_install_property (gobject_class,
PROP_TOP_PADDING,
g_param_spec_uint("top-padding",
P_("Top Padding"),
P_("The padding to insert at the top of the widget."),
0,
G_MAXINT,
0,
GTK_PARAM_READWRITE));
/**
* GtkAlignment:bottom-padding:
*
* The padding to insert at the bottom of the widget.
*
* Since: 2.4
*/
g_object_class_install_property (gobject_class,
PROP_BOTTOM_PADDING,
g_param_spec_uint("bottom-padding",
P_("Bottom Padding"),
P_("The padding to insert at the bottom of the widget."),
0,
G_MAXINT,
0,
GTK_PARAM_READWRITE));
/**
* GtkAlignment:left-padding:
*
* The padding to insert at the left of the widget.
*
* Since: 2.4
*/
g_object_class_install_property (gobject_class,
PROP_LEFT_PADDING,
g_param_spec_uint("left-padding",
P_("Left Padding"),
P_("The padding to insert at the left of the widget."),
0,
G_MAXINT,
0,
GTK_PARAM_READWRITE));
/**
* GtkAlignment:right-padding:
*
* The padding to insert at the right of the widget.
*
* Since: 2.4
*/
g_object_class_install_property (gobject_class,
PROP_RIGHT_PADDING,
g_param_spec_uint("right-padding",
P_("Right Padding"),
P_("The padding to insert at the right of the widget."),
0,
G_MAXINT,
0,
GTK_PARAM_READWRITE));
}
static void
gtk_alignment_init (GtkAlignment *alignment)
{
GtkAlignmentPrivate *priv;
alignment->priv = gtk_alignment_get_instance_private (alignment);
priv = alignment->priv;
gtk_widget_set_has_window (GTK_WIDGET (alignment), FALSE);
gtk_widget_set_redraw_on_allocate (GTK_WIDGET (alignment), FALSE);
priv->xalign = 0.5;
priv->yalign = 0.5;
priv->xscale = 1.0;
priv->yscale = 1.0;
/* Initialize padding with default values: */
priv->padding_top = 0;
priv->padding_bottom = 0;
priv->padding_left = 0;
priv->padding_right = 0;
}
/**
* gtk_alignment_new:
* @xalign: the horizontal alignment of the child widget, from 0 (left) to 1
* (right).
* @yalign: the vertical alignment of the child widget, from 0 (top) to 1
* (bottom).
* @xscale: the amount that the child widget expands horizontally to fill up
* unused space, from 0 to 1.
* A value of 0 indicates that the child widget should never expand.
* A value of 1 indicates that the child widget will expand to fill all of the
* space allocated for the #GtkAlignment.
* @yscale: the amount that the child widget expands vertically to fill up
* unused space, from 0 to 1. The values are similar to @xscale.
*
* Creates a new #GtkAlignment.
*
* Returns: the new #GtkAlignment.
*/
GtkWidget*
gtk_alignment_new (gfloat xalign,
gfloat yalign,
gfloat xscale,
gfloat yscale)
{
GtkAlignment *alignment;
GtkAlignmentPrivate *priv;
alignment = g_object_new (GTK_TYPE_ALIGNMENT, NULL);
priv = alignment->priv;
priv->xalign = CLAMP (xalign, 0.0, 1.0);
priv->yalign = CLAMP (yalign, 0.0, 1.0);
priv->xscale = CLAMP (xscale, 0.0, 1.0);
priv->yscale = CLAMP (yscale, 0.0, 1.0);
return GTK_WIDGET (alignment);
}
static void
gtk_alignment_set_property (GObject *object,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GtkAlignment *alignment = GTK_ALIGNMENT (object);
GtkAlignmentPrivate *priv = alignment->priv;
switch (prop_id)
{
case PROP_XALIGN:
gtk_alignment_set (alignment,
g_value_get_float (value),
priv->yalign,
priv->xscale,
priv->yscale);
break;
case PROP_YALIGN:
gtk_alignment_set (alignment,
priv->xalign,
g_value_get_float (value),
priv->xscale,
priv->yscale);
break;
case PROP_XSCALE:
gtk_alignment_set (alignment,
priv->xalign,
priv->yalign,
g_value_get_float (value),
priv->yscale);
break;
case PROP_YSCALE:
gtk_alignment_set (alignment,
priv->xalign,
priv->yalign,
priv->xscale,
g_value_get_float (value));
break;
/* Padding: */
case PROP_TOP_PADDING:
gtk_alignment_set_padding (alignment,
g_value_get_uint (value),
priv->padding_bottom,
priv->padding_left,
priv->padding_right);
break;
case PROP_BOTTOM_PADDING:
gtk_alignment_set_padding (alignment,
priv->padding_top,
g_value_get_uint (value),
priv->padding_left,
priv->padding_right);
break;
case PROP_LEFT_PADDING:
gtk_alignment_set_padding (alignment,
priv->padding_top,
priv->padding_bottom,
g_value_get_uint (value),
priv->padding_right);
break;
case PROP_RIGHT_PADDING:
gtk_alignment_set_padding (alignment,
priv->padding_top,
priv->padding_bottom,
priv->padding_left,
g_value_get_uint (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gtk_alignment_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GtkAlignment *alignment = GTK_ALIGNMENT (object);
GtkAlignmentPrivate *priv = alignment->priv;
switch (prop_id)
{
case PROP_XALIGN:
g_value_set_float(value, priv->xalign);
break;
case PROP_YALIGN:
g_value_set_float(value, priv->yalign);
break;
case PROP_XSCALE:
g_value_set_float(value, priv->xscale);
break;
case PROP_YSCALE:
g_value_set_float(value, priv->yscale);
break;
/* Padding: */
case PROP_TOP_PADDING:
g_value_set_uint (value, priv->padding_top);
break;
case PROP_BOTTOM_PADDING:
g_value_set_uint (value, priv->padding_bottom);
break;
case PROP_LEFT_PADDING:
g_value_set_uint (value, priv->padding_left);
break;
case PROP_RIGHT_PADDING:
g_value_set_uint (value, priv->padding_right);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
/**
* gtk_alignment_set:
* @alignment: a #GtkAlignment.
* @xalign: the horizontal alignment of the child widget, from 0 (left) to 1
* (right).
* @yalign: the vertical alignment of the child widget, from 0 (top) to 1
* (bottom).
* @xscale: the amount that the child widget expands horizontally to fill up
* unused space, from 0 to 1.
* A value of 0 indicates that the child widget should never expand.
* A value of 1 indicates that the child widget will expand to fill all of the
* space allocated for the #GtkAlignment.
* @yscale: the amount that the child widget expands vertically to fill up
* unused space, from 0 to 1. The values are similar to @xscale.
*
* Sets the #GtkAlignment values.
*/
void
gtk_alignment_set (GtkAlignment *alignment,
gfloat xalign,
gfloat yalign,
gfloat xscale,
gfloat yscale)
{
GtkAlignmentPrivate *priv;
GtkWidget *child;
g_return_if_fail (GTK_IS_ALIGNMENT (alignment));
priv = alignment->priv;
xalign = CLAMP (xalign, 0.0, 1.0);
yalign = CLAMP (yalign, 0.0, 1.0);
xscale = CLAMP (xscale, 0.0, 1.0);
yscale = CLAMP (yscale, 0.0, 1.0);
if ( (priv->xalign != xalign)
|| (priv->yalign != yalign)
|| (priv->xscale != xscale)
|| (priv->yscale != yscale))
{
g_object_freeze_notify (G_OBJECT (alignment));
if (priv->xalign != xalign)
{
priv->xalign = xalign;
g_object_notify (G_OBJECT (alignment), "xalign");
}
if (priv->yalign != yalign)
{
priv->yalign = yalign;
g_object_notify (G_OBJECT (alignment), "yalign");
}
if (priv->xscale != xscale)
{
priv->xscale = xscale;
g_object_notify (G_OBJECT (alignment), "xscale");
}
if (priv->yscale != yscale)
{
priv->yscale = yscale;
g_object_notify (G_OBJECT (alignment), "yscale");
}
g_object_thaw_notify (G_OBJECT (alignment));
child = gtk_bin_get_child (GTK_BIN (alignment));
if (child)
gtk_widget_queue_resize (child);
gtk_widget_queue_draw (GTK_WIDGET (alignment));
}
}
static void
gtk_alignment_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkAlignment *alignment = GTK_ALIGNMENT (widget);
GtkAlignmentPrivate *priv = alignment->priv;
GtkBin *bin;
GtkAllocation child_allocation;
GtkWidget *child;
gint width, height;
gint border_width;
gint padding_horizontal, padding_vertical;
gint baseline;
padding_horizontal = 0;
padding_vertical = 0;
gtk_widget_set_allocation (widget, allocation);
bin = GTK_BIN (widget);
child = gtk_bin_get_child (bin);
if (child && gtk_widget_get_visible (child))
{
gint child_nat_width;
gint child_nat_height;
gint child_width, child_height;
double yalign, yscale;
border_width = gtk_container_get_border_width (GTK_CONTAINER (alignment));
padding_horizontal = priv->padding_left + priv->padding_right;
padding_vertical = priv->padding_top + priv->padding_bottom;
width = MAX (1, allocation->width - padding_horizontal - 2 * border_width);
height = MAX (1, allocation->height - padding_vertical - 2 * border_width);
baseline = gtk_widget_get_allocated_baseline (widget);
if (baseline != -1)
baseline -= border_width + priv->padding_top;
/* If we get a baseline set that means we're baseline aligned, and the parent
honored that. In that case we have to ignore yalign/yscale as we need
yalign based on the baseline and always FILL mode to ensure we can place
the baseline anywhere */
if (baseline != -1)
{
yalign = 0;
yscale = 1.0;
}
else
{
yalign = priv->yalign;
yscale = priv->yscale;
}
if (gtk_widget_get_request_mode (child) == GTK_SIZE_REQUEST_HEIGHT_FOR_WIDTH)
{
gtk_widget_get_preferred_width (child, NULL, &child_nat_width);
child_width = MIN (width, child_nat_width);
gtk_widget_get_preferred_height_for_width (child, child_width, NULL, &child_nat_height);
child_height = MIN (height, child_nat_height);
}
else
{
gtk_widget_get_preferred_height (child, NULL, &child_nat_height);
child_height = MIN (height, child_nat_height);
gtk_widget_get_preferred_width_for_height (child, child_height, NULL, &child_nat_width);
child_width = MIN (width, child_nat_width);
}
if (width > child_width)
child_allocation.width = (child_width *
(1.0 - priv->xscale) +
width * priv->xscale);
else
child_allocation.width = width;
if (height > child_height)
child_allocation.height = (child_height *
(1.0 - yscale) +
height * yscale);
else
child_allocation.height = height;
if (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
child_allocation.x = (1.0 - priv->xalign) * (width - child_allocation.width) + allocation->x + border_width + priv->padding_right;
else
child_allocation.x = priv->xalign * (width - child_allocation.width) + allocation->x + border_width + priv->padding_left;
child_allocation.y = yalign * (height - child_allocation.height) + allocation->y + border_width + priv->padding_top;
gtk_widget_size_allocate_with_baseline (child, &child_allocation, baseline);
}
}
static void
gtk_alignment_get_preferred_size (GtkWidget *widget,
GtkOrientation orientation,
gint for_size,
gint *minimum_size,
gint *natural_size,
gint *minimum_baseline,
gint *natural_baseline)
{
GtkAlignment *alignment = GTK_ALIGNMENT (widget);
GtkAlignmentPrivate *priv = alignment->priv;
GtkWidget *child;
guint minimum, natural;
guint top_offset;
guint border;
if (minimum_baseline)
*minimum_baseline = -1;
if (natural_baseline)
*natural_baseline = -1;
border = gtk_container_get_border_width (GTK_CONTAINER (widget));
natural = minimum = border * 2;
top_offset = border;
if ((child = gtk_bin_get_child (GTK_BIN (widget))) && gtk_widget_get_visible (child))
{
gint child_min, child_nat;
gint child_min_baseline = -1, child_nat_baseline = -1;
/* Request extra space for the padding: */
if (orientation == GTK_ORIENTATION_HORIZONTAL)
{
minimum += (priv->padding_left + priv->padding_right);
if (for_size < 0)
gtk_widget_get_preferred_width (child, &child_min, &child_nat);
else
{
gint min_height;
gtk_widget_get_preferred_height (child, &min_height, NULL);
for_size -= (priv->padding_top + priv->padding_bottom);
if (for_size > min_height)
for_size = (min_height * (1.0 - priv->yscale) +
for_size * priv->yscale);
gtk_widget_get_preferred_width_for_height (child, for_size, &child_min, &child_nat);
}
}
else
{
minimum += (priv->padding_top + priv->padding_bottom);
top_offset += priv->padding_top;
if (for_size < 0)
gtk_widget_get_preferred_height_and_baseline_for_width (child, -1, &child_min, &child_nat, &child_min_baseline, &child_nat_baseline);
else
{
gint min_width;
gtk_widget_get_preferred_width (child, &min_width, NULL);
for_size -= (priv->padding_left + priv->padding_right);
if (for_size > min_width)
for_size = (min_width * (1.0 - priv->xscale) +
for_size * priv->xscale);
gtk_widget_get_preferred_height_and_baseline_for_width (child, for_size, &child_min, &child_nat, &child_min_baseline, &child_nat_baseline);
}
if (minimum_baseline && child_min_baseline >= 0)
*minimum_baseline = child_min_baseline + top_offset;
if (natural_baseline && child_nat_baseline >= 0)
*natural_baseline = child_nat_baseline + top_offset;
}
natural = minimum;
minimum += child_min;
natural += child_nat;
}
if (minimum_size)
*minimum_size = minimum;
if (natural_size)
*natural_size = natural;
}
static void
gtk_alignment_get_preferred_width (GtkWidget *widget,
gint *minimum_size,
gint *natural_size)
{
gtk_alignment_get_preferred_size (widget, GTK_ORIENTATION_HORIZONTAL, -1, minimum_size, natural_size, NULL, NULL);
}
static void
gtk_alignment_get_preferred_height (GtkWidget *widget,
gint *minimum_size,
gint *natural_size)
{
gtk_alignment_get_preferred_size (widget, GTK_ORIENTATION_VERTICAL, -1, minimum_size, natural_size, NULL, NULL);
}
static void
gtk_alignment_get_preferred_width_for_height (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size)
{
gtk_alignment_get_preferred_size (widget, GTK_ORIENTATION_HORIZONTAL, for_size, minimum_size, natural_size, NULL, NULL);
}
static void
gtk_alignment_get_preferred_height_for_width (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size)
{
gtk_alignment_get_preferred_size (widget, GTK_ORIENTATION_VERTICAL, for_size, minimum_size, natural_size, NULL, NULL);
}
static void
gtk_alignment_get_preferred_height_and_baseline_for_width (GtkWidget *widget,
gint for_size,
gint *minimum_size,
gint *natural_size,
gint *minimum_baseline,
gint *natural_baseline)
{
gtk_alignment_get_preferred_size (widget, GTK_ORIENTATION_VERTICAL, for_size, minimum_size, natural_size, minimum_baseline, natural_baseline);
}
/**
* gtk_alignment_set_padding:
* @alignment: a #GtkAlignment
* @padding_top: the padding at the top of the widget
* @padding_bottom: the padding at the bottom of the widget
* @padding_left: the padding at the left of the widget
* @padding_right: the padding at the right of the widget.
*
* Sets the padding on the different sides of the widget.
* The padding adds blank space to the sides of the widget. For instance,
* this can be used to indent the child widget towards the right by adding
* padding on the left.
*
* Since: 2.4
*/
void
gtk_alignment_set_padding (GtkAlignment *alignment,
guint padding_top,
guint padding_bottom,
guint padding_left,
guint padding_right)
{
GtkAlignmentPrivate *priv;
GtkWidget *child;
g_return_if_fail (GTK_IS_ALIGNMENT (alignment));
priv = alignment->priv;
g_object_freeze_notify (G_OBJECT (alignment));
if (priv->padding_top != padding_top)
{
priv->padding_top = padding_top;
g_object_notify (G_OBJECT (alignment), "top-padding");
}
if (priv->padding_bottom != padding_bottom)
{
priv->padding_bottom = padding_bottom;
g_object_notify (G_OBJECT (alignment), "bottom-padding");
}
if (priv->padding_left != padding_left)
{
priv->padding_left = padding_left;
g_object_notify (G_OBJECT (alignment), "left-padding");
}
if (priv->padding_right != padding_right)
{
priv->padding_right = padding_right;
g_object_notify (G_OBJECT (alignment), "right-padding");
}
g_object_thaw_notify (G_OBJECT (alignment));
/* Make sure that the widget and children are redrawn with the new setting: */
child = gtk_bin_get_child (GTK_BIN (alignment));
if (child)
gtk_widget_queue_resize (child);
gtk_widget_queue_draw (GTK_WIDGET (alignment));
}
/**
* gtk_alignment_get_padding:
* @alignment: a #GtkAlignment
* @padding_top: (out) (allow-none): location to store the padding for
* the top of the widget, or %NULL
* @padding_bottom: (out) (allow-none): location to store the padding
* for the bottom of the widget, or %NULL
* @padding_left: (out) (allow-none): location to store the padding
* for the left of the widget, or %NULL
* @padding_right: (out) (allow-none): location to store the padding
* for the right of the widget, or %NULL
*
* Gets the padding on the different sides of the widget.
* See gtk_alignment_set_padding ().
*
* Since: 2.4
*/
void
gtk_alignment_get_padding (GtkAlignment *alignment,
guint *padding_top,
guint *padding_bottom,
guint *padding_left,
guint *padding_right)
{
GtkAlignmentPrivate *priv;
g_return_if_fail (GTK_IS_ALIGNMENT (alignment));
priv = alignment->priv;
if(padding_top)
*padding_top = priv->padding_top;
if(padding_bottom)
*padding_bottom = priv->padding_bottom;
if(padding_left)
*padding_left = priv->padding_left;
if(padding_right)
*padding_right = priv->padding_right;
}