src/geanywraplabel.c

   1 /*
   2  *      geanywraplabel.c - this file is part of Geany, a fast and lightweight IDE
   3  *
   4  *      Copyright 2009-2012 Enrico Tröger <enrico(dot)troeger(at)uvena(dot)de>
   5  *      Copyright 2009-2012 Nick Treleaven <nick(dot)treleaven(at)btinternet(dot)com>
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; either version 2 of the License, or
  10  *      (at your option) any later version.
  11  *
  12  *      This program is distributed in the hope that it will be useful,
  13  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *      GNU General Public License for more details.
  16  *
  17  *      You should have received a copy of the GNU General Public License along
  18  *      with this program; if not, write to the Free Software Foundation, Inc.,
  19  *      51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  */
  21
  22 /*
  23  * A GtkLabel subclass that can wrap to any width, unlike GtkLabel which has a fixed wrap point.
  24  * (inspired by libview's WrapLabel, http://view.sourceforge.net)
  25  */
  26
  27
  28 #include "geany.h"
  29 #include "utils.h"
  30 #include "geanywraplabel.h"
  31
  32
  33 struct _GeanyWrapLabelClass
  34 {
  35         GtkLabelClass parent_class;
  36 };
  37
  38 typedef struct
  39 {
  40         gint wrap_width;
  41         gint wrap_height;
  42 } GeanyWrapLabelPrivate;
  43
  44 struct _GeanyWrapLabel
  45 {
  46         GtkLabel parent;
  47         GeanyWrapLabelPrivate *priv;
  48 };
  49
  50
  51 #if GTK_CHECK_VERSION(3, 0, 0)
  52 static gboolean geany_wrap_label_draw(GtkWidget *widget, cairo_t *cr);
  53 static void geany_wrap_label_get_preferred_width (GtkWidget *widget,
  54                 gint *minimal_width, gint *natural_width);
  55 static void geany_wrap_label_get_preferred_height (GtkWidget *widget,
  56                 gint *minimal_height, gint *natural_height);
  57 static void geany_wrap_label_get_preferred_width_for_height (GtkWidget *widget,
  58                 gint height, gint *minimal_width, gint *natural_width);
  59 static void geany_wrap_label_get_preferred_height_for_width (GtkWidget *widget,
  60                 gint width, gint *minimal_height, gint *natural_height);
  61 static GtkSizeRequestMode geany_wrap_label_get_request_mode(GtkWidget *widget);
  62 #else
  63 static gboolean geany_wrap_label_expose         (GtkWidget *widget, GdkEventExpose *event);
  64 static void geany_wrap_label_size_request       (GtkWidget *widget, GtkRequisition *req);
  65 #endif
  66 static void geany_wrap_label_size_allocate      (GtkWidget *widget, GtkAllocation *alloc);
  67 static void geany_wrap_label_set_wrap_width     (GtkWidget *widget, gint width);
  68 static void geany_wrap_label_label_notify       (GObject *object, GParamSpec *pspec, gpointer data);
  69
  70 G_DEFINE_TYPE(GeanyWrapLabel, geany_wrap_label, GTK_TYPE_LABEL)
  71
  72
  73 static void geany_wrap_label_class_init(GeanyWrapLabelClass *klass)
  74 {
  75         GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
  76
  77         widget_class->size_allocate = geany_wrap_label_size_allocate;
  78 #if GTK_CHECK_VERSION(3, 0, 0)
  79         widget_class->draw = geany_wrap_label_draw;
  80         widget_class->get_preferred_width = geany_wrap_label_get_preferred_width;
  81         widget_class->get_preferred_width_for_height = geany_wrap_label_get_preferred_width_for_height;
  82         widget_class->get_preferred_height = geany_wrap_label_get_preferred_height;
  83         widget_class->get_preferred_height_for_width = geany_wrap_label_get_preferred_height_for_width;
  84         widget_class->get_request_mode = geany_wrap_label_get_request_mode;
  85 #else
  86         widget_class->size_request = geany_wrap_label_size_request;
  87         widget_class->expose_event = geany_wrap_label_expose;
  88 #endif
  89
  90         g_type_class_add_private(klass, sizeof (GeanyWrapLabelPrivate));
  91 }
  92
  93
  94 static void geany_wrap_label_init(GeanyWrapLabel *self)
  95 {
  96         self->priv = G_TYPE_INSTANCE_GET_PRIVATE(self,
  97                 GEANY_WRAP_LABEL_TYPE, GeanyWrapLabelPrivate);
  98
  99         self->priv->wrap_width = 0;
 100         self->priv->wrap_height = 0;
 101
 102         g_signal_connect(self, "notify::label", G_CALLBACK(geany_wrap_label_label_notify), NULL);
 103         gtk_misc_set_alignment(GTK_MISC(self), 0.0, 0.0);
 104 }
 105
 106
 107 /* Sets the point at which the text should wrap. */
 108 static void geany_wrap_label_set_wrap_width(GtkWidget *widget, gint width)
 109 {
 110         GeanyWrapLabel *self = GEANY_WRAP_LABEL(widget);
 111         PangoLayout *layout;
 112
 113         if (width <= 0)
 114                 return;
 115
 116         layout = gtk_label_get_layout(GTK_LABEL(widget));
 117
 118         /*
 119         * We may need to reset the wrap width, so do this regardless of whether
 120         * or not we've changed the width.
 121         */
 122         pango_layout_set_width(layout, width * PANGO_SCALE);
 123         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
 124         pango_layout_get_pixel_size(layout, NULL, &self->priv->wrap_height);
 125
 126         if (self->priv->wrap_width != width)
 127         {
 128                 self->priv->wrap_width = width;
 129                 gtk_widget_queue_resize(widget);
 130         }
 131 }
 132
 133
 134 /* updates the wrap width when the label text changes */
 135 static void geany_wrap_label_label_notify(GObject *object, GParamSpec *pspec, gpointer data)
 136 {
 137         GeanyWrapLabel *self = GEANY_WRAP_LABEL(object);
 138
 139         geany_wrap_label_set_wrap_width(GTK_WIDGET(object), self->priv->wrap_width);
 140 }
 141
 142
 143 #if GTK_CHECK_VERSION(3, 0, 0)
 144 /* makes sure the layout is setup for rendering and chains to parent renderer */
 145 static gboolean geany_wrap_label_draw(GtkWidget *widget, cairo_t *cr)
 146 {
 147         GeanyWrapLabel *self = GEANY_WRAP_LABEL(widget);
 148         PangoLayout *layout = gtk_label_get_layout(GTK_LABEL(widget));
 149
 150         pango_layout_set_width(layout, self->priv->wrap_width * PANGO_SCALE);
 151         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
 152
 153         return (* GTK_WIDGET_CLASS(geany_wrap_label_parent_class)->draw)(widget, cr);
 154 }
 155
 156
 157 static void geany_wrap_label_get_preferred_width (GtkWidget *widget,
 158                 gint *minimal_width, gint *natural_width)
 159 {
 160         *minimal_width = *natural_width = 0;
 161 }
 162
 163
 164 static void geany_wrap_label_get_preferred_width_for_height (GtkWidget *widget,
 165                 gint height, gint *minimal_width, gint *natural_width)
 166 {
 167         PangoLayout *layout = gtk_label_get_layout(GTK_LABEL(widget));;
 168
 169         pango_layout_set_height(layout, height * PANGO_SCALE);
 170         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
 171         pango_layout_get_pixel_size(layout, natural_width, NULL);
 172
 173         *minimal_width = 0;
 174 }
 175
 176
 177 static void geany_wrap_label_get_preferred_height (GtkWidget *widget,
 178                 gint *minimal_height, gint *natural_height)
 179 {
 180         *minimal_height = *natural_height = GEANY_WRAP_LABEL(widget)->priv->wrap_height;
 181 }
 182
 183
 184 static void geany_wrap_label_get_preferred_height_for_width (GtkWidget *widget,
 185                 gint width, gint *minimal_height, gint *natural_height)
 186 {
 187         PangoLayout *layout = gtk_label_get_layout(GTK_LABEL(widget));
 188
 189         pango_layout_set_width(layout, width * PANGO_SCALE);
 190         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
 191         pango_layout_get_pixel_size(layout, NULL, natural_height);
 192
 193         *minimal_height = *natural_height;
 194 }
 195
 196
 197 static GtkSizeRequestMode geany_wrap_label_get_request_mode(GtkWidget *widget)
 198 {
 199         return GTK_SIZE_REQUEST_WIDTH_FOR_HEIGHT;
 200 }
 201
 202 #else /* GTK3 */
 203
 204 /* makes sure the layout is setup for rendering and chains to parent renderer */
 205 static gboolean geany_wrap_label_expose(GtkWidget *widget, GdkEventExpose *event)
 206 {
 207         GeanyWrapLabel *self = GEANY_WRAP_LABEL(widget);
 208         PangoLayout *layout = gtk_label_get_layout(GTK_LABEL(widget));
 209
 210         pango_layout_set_width(layout, self->priv->wrap_width * PANGO_SCALE);
 211         pango_layout_set_wrap(layout, PANGO_WRAP_WORD_CHAR);
 212
 213         return (* GTK_WIDGET_CLASS(geany_wrap_label_parent_class)->expose_event)(widget, event);
 214 }
 215
 216
 217 /* Forces the height to be the size necessary for the Pango layout, while allowing the
 218  * width to be flexible. */
 219 static void geany_wrap_label_size_request(GtkWidget *widget, GtkRequisition *req)
 220 {
 221         req->width = 0;
 222         req->height = GEANY_WRAP_LABEL(widget)->priv->wrap_height;
 223 }
 224 #endif /* GTK3 */
 225
 226
 227 /* Sets the wrap width to the width allocated to us. */
 228 static void geany_wrap_label_size_allocate(GtkWidget *widget, GtkAllocation *alloc)
 229 {
 230         (* GTK_WIDGET_CLASS(geany_wrap_label_parent_class)->size_allocate)(widget, alloc);
 231
 232         geany_wrap_label_set_wrap_width(widget, alloc->width);
 233
 234 #if GTK_CHECK_VERSION(3, 0, 0)
 235 {
 236         /* ask the parent to recompute our size, because it seems GTK3 size
 237          * caching is too aggressive */
 238         GtkWidget *parent = gtk_widget_get_parent(widget);
 239         if (GTK_IS_CONTAINER(parent))
 240                 gtk_container_check_resize(GTK_CONTAINER(parent));
 241 }
 242 #endif
 243 }
 244
 245
 246 GtkWidget *geany_wrap_label_new(const gchar *text)
 247 {
 248         return g_object_new(GEANY_WRAP_LABEL_TYPE, "label", text, NULL);
 249 }