examplewindow.cc

Developing with Gnome一书examples例子代码

#include "ExampleWindow.h"
#include <sstream>

ExampleWindow::ExampleWindow(
  BaseObjectType* base_object,
  const Glib::RefPtr<Gnome::Glade::Xml>& glade_xml)
  : Gtk::Window(base_object)
{
  // Get the client and tell it we want to monitor /apps/nautilus/preferences
  d_conf_client = Gnome::Conf::Client::get_default_client();
  d_conf_client->add_dir("/apps/nautilus/preferences");


  /* First, setup the checkbutton for the always_use_browser key */

  // Get the check_button
  glade_xml->get_widget("BrowserMode", d_browser_checkbutton);

  // Connect the check_button to a callback that can toggle it when the option
  // is changed by some outside program.
  d_conf_client->notify_add(
    "/apps/nautilus/preferences/always_use_browser",
    sigc::mem_fun(*this, &ExampleWindow::browser_key_changed)
    );

  // Connect the check_button's clicked callback up so that it can change the
  // gconf setting.
  d_browser_checkbutton->signal_clicked().connect(
    sigc::mem_fun(*this, &ExampleWindow::browser_key_toggled) );

  // Determine whether button should start activated or not
  d_old_browser_setting = 
    d_conf_client->get_bool("/apps/nautilus/preferences/always_use_browser");
  d_browser_checkbutton->set_active(d_old_browser_setting);


  /* Second, setup the text entry for the show_image_thumbnails key */

  // Get the Entry
  glade_xml->get_widget("ShowThumbnailsEntry", d_show_thumbnail_entry);

  // Connect the show thumbnail entry to a callback that can toggle it
  // when the option is changed by some outside program.
  d_conf_client->notify_add(
    "/apps/nautilus/preferences/show_image_thumbnails",
    sigc::mem_fun(*this, &ExampleWindow::show_thumbnails_key_changed)
    );

  // Connect the show thumbnail entry's activated callback up so that
  // it can change the gconf setting.
  d_show_thumbnail_entry->signal_activate().connect(
    sigc::mem_fun(*this, &ExampleWindow::show_thumbnails_modified) );

  // Determine the starting value of this key
  d_old_show_thumbnails_setting =
    d_conf_client->get_string(
      "/apps/nautilus/preferences/show_image_thumbnails");
  d_show_thumbnail_entry->set_text(d_old_show_thumbnails_setting);


  /* Third, setup the text entry for the thumbnail_limit key */

  // Get the Entry
  glade_xml->get_widget("ThumbnailLimitEntry", d_thumbnail_limit_entry);

  // Connect the thumbnail limit entry to a callback that can toggle
  // it when the option is changed by some outside program.
  d_conf_client->notify_add(
    "/apps/nautilus/preferences/thumbnail_limit",
    sigc::mem_fun(*this, &ExampleWindow::thumbnail_limit_key_changed)
    );

  // Connect the thumbnail limit entry's activated callback up so that
  // it can change the gconf setting.
  d_thumbnail_limit_entry->signal_activate().connect(
    sigc::mem_fun(*this, &ExampleWindow::thumbnail_limit_modified) );

  // Determine the starting value of this key
  d_old_thumbnail_limit =
    d_conf_client->get_int("/apps/nautilus/preferences/thumbnail_limit");
  gchar temp_string[20];
  sprintf(temp_string, "%d", d_old_thumbnail_limit);
  d_thumbnail_limit_entry->set_text(temp_string);



  // Get the close button and connect it to hide
  Gtk::Button* close_button;
  glade_xml->get_widget("CloseButton", close_button);
  close_button->signal_clicked().connect(
    sigc::mem_fun(*this, &Gtk::Widget::hide));
}

ExampleWindow::~ExampleWindow()
{
}

void
ExampleWindow::browser_key_changed(guint cnxn_id, Gnome::Conf::Entry entry)
{
  // Make sure the preference has a valid value
  if (entry.get_value().get_type() == Gnome::Conf::VALUE_BOOL) {
    // Get the new value
    bool new_browser_setting = entry.get_value().get_bool();

    // Try to handle asynchronous-ness of GConf and prevent calling
    // checkbutton_toggled again if this function was called as a
    // result of the d_conf_client->set() function call.
    if (new_browser_setting != d_old_browser_setting) {
      d_old_browser_setting = new_browser_setting;
      d_browser_checkbutton->set_active(new_browser_setting);
    }
  }
}

void
ExampleWindow::browser_key_toggled()
{
  // Determine whether the checkbutton is already set or not
  bool is_set = d_browser_checkbutton->get_active();
 
  // Try to handle asynchronous-ness of GConf and prevent calling
  // key_changed again if this function was called as a result of the
  // d_checkbutton->set_active() function call.
  if (is_set != d_old_browser_setting) {
    d_old_browser_setting = is_set;
    d_conf_client->set("/apps/nautilus/preferences/always_use_browser", is_set);
  }
}

void
ExampleWindow::show_thumbnails_key_changed(
  guint cnxn_id, 
  Gnome::Conf::Entry entry)
{
  // Make sure the preference has a valid value
  if (entry.get_value().get_type() == Gnome::Conf::VALUE_STRING) {
    // Get the new value
    Glib::ustring new_setting = entry.get_value().get_string();

    // Check if it seems valid, give a warning if it doesn't
    if ((new_setting != "always") &&
        (new_setting != "local_only") &&
        (new_setting != "never"))
    {
      g_warning("Unrecognized value specified by external program...\n");
    }

    // Use the new value if it's different than the old
    if (new_setting != d_old_show_thumbnails_setting) {
      d_old_show_thumbnails_setting = new_setting;
      d_show_thumbnail_entry->set_text(new_setting);
    }
  }
}

void
ExampleWindow::show_thumbnails_modified()
{
  // Get the current value
  Glib::ustring cur_value = d_show_thumbnail_entry->get_text();
 
  if ((cur_value == "always")     ||
      (cur_value == "local_only") ||
      (cur_value == "never")) {
    if (cur_value != d_old_show_thumbnails_setting) {
      d_old_show_thumbnails_setting = cur_value;
      d_conf_client->set("/apps/nautilus/preferences/show_image_thumbnails",
                         cur_value);
    }
  } else {
    g_warning("This program needs an error window to warn you that you typed an invalid value.\n");
    d_show_thumbnail_entry->set_text(d_old_show_thumbnails_setting);
  }
}

void
ExampleWindow::thumbnail_limit_key_changed(
  guint cnxn_id, 
  Gnome::Conf::Entry entry)
{
  // Make sure the preference has a valid value
  if (entry.get_value().get_type() == Gnome::Conf::VALUE_INT) {
    // Get the new value
    gint new_value = entry.get_value().get_int();

    // Check if it seems valid, give a warning if it doesn't
    if (new_value < 0) {
      g_warning("Bad value seems to have been set by external program.\n");
    }

    // Use the new value if it's different than the old
    if (new_value != d_old_thumbnail_limit) {
      d_old_thumbnail_limit = new_value;
      gchar temp_string[20];
      sprintf(temp_string, "%d", d_old_thumbnail_limit);
      d_thumbnail_limit_entry->set_text(temp_string);
    }
  }
}

void
ExampleWindow::thumbnail_limit_modified()
{
  // Get the current value
  Glib::ustring cur_value = d_thumbnail_limit_entry->get_text();
  /*
  size_type bad_char_position = cur_value.find_first_not_of("1234567890");

  gint new_value = 0;
  if (bad_char_position != string::npos)
    new_value = atoi(cur_value->c_str());
  */

  std::istringstream sstr(cur_value);
  gint new_value;
  sstr >> new_value;

  if ( !sstr.fail() && new_value >= 0) {
    if (new_value != d_old_thumbnail_limit) {
      d_old_thumbnail_limit = new_value;
      d_conf_client->set("/apps/nautilus/preferences/thumbnail_limit",
                         new_value);
    }
  } else {
    g_warning("This program needs an error window to warn you that you typed an invalid value.\n");
    gchar temp_string[20];
    sprintf(temp_string, "%d", d_old_thumbnail_limit);
    d_thumbnail_limit_entry->set_text(temp_string);
  }
}