GTK+系統中的對話框(GTK+ dialogs)
在接下來的章節中我們將着重介紹GTK+系統中的對話框。
對話框窗口是衆多GUI應用程序中不可或缺的部分。對話框經常是很多人進行信息交流的橋樑。在計算機中,對話框也經常扮演着我們和應用程序進行對話的工具。對話框可以用來輸入數據,修改數據,或者改變應用程序的使用設置信息。對話框是一個人機交互的重要手段。
消息對話框(Message dialogs)
消息對話框可以方便的在你的應用程序中,跳出來顯示一些有用的信息。當然可以包含文字或者圖象。
#include <gtk/gtk.h> void show_info(GtkWidget *widget, gpointer window) { GtkWidget *dialog; dialog = gtk_message_dialog_new(window, GTK_DIALOG_DESTROY_WITH_PARENT, GTK_MESSAGE_INFO, GTK_BUTTONS_OK, "Download Completed", "title"); gtk_window_set_title(GTK_WINDOW(dialog), "Information"); gtk_dialog_run(GTK_DIALOG(dialog)); gtk_widget_destroy(dialog); } void show_error(GtkWidget *widget, gpointer window) { GtkWidget *dialog; dialog = gtk_message_dialog_new(window, GTK_DIALOG_DESTROY_WITH_PARENT, GTK_MESSAGE_ERROR, GTK_BUTTONS_OK, "Error loading file"); gtk_window_set_title(GTK_WINDOW(dialog), "Error"); gtk_dialog_run(GTK_DIALOG(dialog)); gtk_widget_destroy(dialog); } void show_question(GtkWidget *widget, gpointer window) { GtkWidget *dialog; dialog = gtk_message_dialog_new(window, GTK_DIALOG_DESTROY_WITH_PARENT, GTK_MESSAGE_QUESTION, GTK_BUTTONS_YES_NO, "Are you sure to quit?"); gtk_window_set_title(GTK_WINDOW(dialog), "Question"); gtk_dialog_run(GTK_DIALOG(dialog)); gtk_widget_destroy(dialog); } void show_warning(GtkWidget *widget, gpointer window) { GtkWidget *dialog; dialog = gtk_message_dialog_new(window, GTK_DIALOG_DESTROY_WITH_PARENT, GTK_MESSAGE_WARNING, GTK_BUTTONS_OK, "Unallowed operation"); gtk_window_set_title(GTK_WINDOW(dialog), "Warning"); gtk_dialog_run(GTK_DIALOG(dialog)); gtk_widget_destroy(dialog); } int main( int argc, char *argv[]) { GtkWidget *window; GtkWidget *table; GtkWidget *info; GtkWidget *warn; GtkWidget *que; GtkWidget *err; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); gtk_window_set_default_size(GTK_WINDOW(window), 220, 150); gtk_window_set_title(GTK_WINDOW(window), "Message dialogs"); table = gtk_table_new(2, 2, TRUE); gtk_table_set_row_spacings(GTK_TABLE(table), 2); gtk_table_set_col_spacings(GTK_TABLE(table), 2); info = gtk_button_new_with_label("Info"); warn = gtk_button_new_with_label("Warning"); que = gtk_button_new_with_label("Question"); err = gtk_button_new_with_label("Error"); gtk_table_attach(GTK_TABLE(table), info, 0, 1, 0, 1, GTK_FILL, GTK_FILL, 3, 3); gtk_table_attach(GTK_TABLE(table), warn, 1, 2, 0, 1, GTK_FILL, GTK_FILL, 3, 3); gtk_table_attach(GTK_TABLE(table), que, 0, 1, 1, 2, GTK_FILL, GTK_FILL, 3, 3); gtk_table_attach(GTK_TABLE(table), err, 1, 2, 1, 2, GTK_FILL, GTK_FILL, 3, 3); gtk_container_add(GTK_CONTAINER(window), table); gtk_container_set_border_width(GTK_CONTAINER(window), 15); g_signal_connect(G_OBJECT(info), "clicked", G_CALLBACK(show_info), (gpointer) window); g_signal_connect(G_OBJECT(warn), "clicked", G_CALLBACK(show_warning), (gpointer) window); g_signal_connect(G_OBJECT(que), "clicked", G_CALLBACK(show_question), (gpointer) window); g_signal_connect(G_OBJECT(err), "clicked", G_CALLBACK(show_error), (gpointer) window); g_signal_connect_swapped(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), G_OBJECT(window)); gtk_widget_show_all(window); gtk_main(); return 0; }
在上面的示例中,我們展示了四種消息對話框。Information, Warning, Question和 Error 消息對話框。
GtkWidget *dialog; dialog = gtk_message_dialog_new(window, GTK_DIALOG_DESTROY_WITH_PARENT, GTK_MESSAGE_QUESTION, GTK_BUTTONS_YES_NO, "Are you sure to quit?");
在函數show_question() 中,我們安排跳出了一個對話框。至於消息對話框是用函數gtk_message_dialog_new()
。 至於函數中的參數設置是在說明你想要顯示那種樣式的對話框。系統常量 GTK_MESSAGE_QUESTION
是在說明我們想要生成一個question對話框。系統常量GTK_BUTTONS_YES_NO
將生成“yes“和”no “兩個按鈕。最後一個參數是我們想要在對話框中顯示的文字。
gtk_window_set_title(GTK_WINDOW(dialog), "Warning"); gtk_dialog_run(GTK_DIALOG(dialog)); gtk_widget_destroy(dialog);
這裏,我們爲我們剛剛身成的消息對話框設置一個標題。最後運行這個對話框,接着設置了這個對話框必須手動關閉。
GTK應用程序信息對話框(GtkAboutDialog)
GTK應用程序對話框的是用來顯示應用程序中的有關提示信息的。GTK應用程序對話框可以顯示應用程序的logo ,名稱,版本,版權,網站或者認證之類的信息。當然也可以在其中,給程序的作者,文檔整理者,翻譯者帶來名譽上的聲望。
#include <gtk/gtk.h> void show_about(GtkWidget *widget, gpointer data) { GdkPixbuf *pixbuf = gdk_pixbuf_new_from_file("battery.png", NULL); GtkWidget *dialog = gtk_about_dialog_new(); gtk_about_dialog_set_name(GTK_ABOUT_DIALOG(dialog), "Battery"); gtk_about_dialog_set_version(GTK_ABOUT_DIALOG(dialog), "0.9"); gtk_about_dialog_set_copyright(GTK_ABOUT_DIALOG(dialog), "(c) Jan Bodnar"); gtk_about_dialog_set_comments(GTK_ABOUT_DIALOG(dialog), "Battery is a simple tool for battery checking."); gtk_about_dialog_set_website(GTK_ABOUT_DIALOG(dialog), "http://www.batteryhq.net"); gtk_about_dialog_set_logo(GTK_ABOUT_DIALOG(dialog), pixbuf); g_object_unref(pixbuf), pixbuf = NULL; gtk_dialog_run(GTK_DIALOG (dialog)); gtk_widget_destroy(dialog); } int main( int argc, char *argv[]) { GtkWidget *window; GtkWidget *about; GdkPixbuf *battery; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); gtk_window_set_default_size(GTK_WINDOW(window), 220, 150); gtk_window_set_title(GTK_WINDOW(window), "Battery"); gtk_container_set_border_width(GTK_CONTAINER(window), 15); gtk_widget_add_events(window, GDK_BUTTON_PRESS_MASK); battery = gtk_image_get_pixbuf(GTK_IMAGE( gtk_image_new_from_file("battery.png"))); g_signal_connect(G_OBJECT(window), "button-press-event", G_CALLBACK(show_about), (gpointer) window); g_signal_connect_swapped(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), G_OBJECT(window)); gtk_widget_show_all(window); gtk_main(); return 0; }
上面的代碼中我們用了構件GtkAboutDialog 以及該構件的一些特性。我們單擊應用程序客戶端窗口,該GTK應用程序信息對話框就會跳出來。:—)
GtkWidget *dialog = gtk_about_dialog_new();
我們要生成一個新的GtkAboutDialog構件。
gtk_about_dialog_set_name(GTK_ABOUT_DIALOG(dialog), "Battery"); gtk_about_dialog_set_version(GTK_ABOUT_DIALOG(dialog), "0.9"); gtk_about_dialog_set_copyright(GTK_ABOUT_DIALOG(dialog), "(c) Jan Bodnar");
這個函數是用來設置一個名字,版本以及版權的。
GdkPixbuf *pixbuf = gdk_pixbuf_new_from_file("battery.png", NULL); ... gtk_about_dialog_set_logo(GTK_ABOUT_DIALOG(dialog), pixbuf); g_object_unref(pixbuf), pixbuf = NULL;
這段代碼爲我們的對話框設置了一個logo圖標。
GTK字體選擇對話框(GtkFontSelectionDialog)
GTK字體選擇對話框是用來讓我們選擇字體的。這在一些應用程序中很有代表性。尤其是一些文字處理或者文字排版的軟件。
#include <gtk/gtk.h> void select_font(GtkWidget *widget, gpointer label) { GtkResponseType result; GtkWidget *dialog = gtk_font_selection_dialog_new("Select Font"); result = gtk_dialog_run(GTK_DIALOG(dialog)); if (result == GTK_RESPONSE_OK || result == GTK_RESPONSE_APPLY) { PangoFontDescription *font_desc; gchar *fontname = gtk_font_selection_dialog_get_font_name( GTK_FONT_SELECTION_DIALOG(dialog)); font_desc = pango_font_description_from_string(fontname); gtk_widget_modify_font(GTK_WIDGET(label), font_desc); g_free(fontname); } gtk_widget_destroy(dialog); } int main( int argc, char *argv[]) { GtkWidget *window; GtkWidget *label; GtkWidget *vbox; GtkWidget *toolbar; GtkToolItem *font; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); gtk_window_set_default_size(GTK_WINDOW(window), 280, 200); gtk_window_set_title(GTK_WINDOW(window), "Font Selection Dialog"); vbox = gtk_vbox_new(FALSE, 0); gtk_container_add(GTK_CONTAINER(window), vbox); toolbar = gtk_toolbar_new(); gtk_toolbar_set_style(GTK_TOOLBAR(toolbar), GTK_TOOLBAR_ICONS); gtk_container_set_border_width(GTK_CONTAINER(toolbar), 2); font = gtk_tool_button_new_from_stock(GTK_STOCK_SELECT_FONT); gtk_toolbar_insert(GTK_TOOLBAR(toolbar), font, -1); gtk_box_pack_start(GTK_BOX(vbox), toolbar, FALSE, FALSE, 5); label = gtk_label_new("ZetCode"); gtk_label_set_justify(GTK_LABEL(label), GTK_JUSTIFY_CENTER); gtk_box_pack_start(GTK_BOX(vbox), label, TRUE, FALSE, 5); g_signal_connect(G_OBJECT(font), "clicked", G_CALLBACK(select_font), label); g_signal_connect_swapped(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), NULL); gtk_widget_show_all(window); gtk_main(); return 0; }
在上面的代碼示例中,我們在窗口的中央放置了一個簡單標籤;如果你點擊工具欄按鈕,那麼字體選擇對話框就會跳出來 .
GtkWidget *dialog = gtk_font_selection_dialog_new("Select Font"); result = gtk_dialog_run(GTK_DIALOG(dialog));
我們生成了一個字體選擇對話框構件即 GtkFontSelectionDialog。
if (result == GTK_RESPONSE_OK || result == GTK_RESPONSE_APPLY) { PangoFontDescription *font_desc; gchar *fontname = gtk_font_selection_dialog_get_font_name( GTK_FONT_SELECTION_DIALOG(dialog)); font_desc = pango_font_description_from_string(fontname); gtk_widget_modify_font(GTK_WIDGET(label), font_desc); g_free(fontname); }
如果用戶點擊“OK“按鈕。我們就得到了字體的相關信息,並且把該設置信息作用於前面生成的標籤。
GTK色彩選擇對話框(GtkColorSelectionDialog)
顧名思義GTK色彩選擇對話框就是一個用於顏色選擇的對話框。
#include <gtk/gtk.h> void select_font(GtkWidget *widget, gpointer label) { GtkResponseType result; GtkColorSelection *colorsel; GtkWidget *dialog = gtk_color_selection_dialog_new("Font Color"); result = gtk_dialog_run(GTK_DIALOG(dialog)); if (result == GTK_RESPONSE_OK) { GdkColor color; colorsel = GTK_COLOR_SELECTION( GTK_COLOR_SELECTION_DIALOG(dialog)->colorsel); gtk_color_selection_get_current_color(colorsel, &color); gtk_widget_modify_fg(GTK_WIDGET(label), GTK_STATE_NORMAL, &color); } gtk_widget_destroy(dialog); } int main( int argc, char *argv[]) { GtkWidget *window; GtkWidget *widget; GtkWidget *label; GtkWidget *vbox; GtkWidget *toolbar; GtkToolItem *font; gtk_init(&argc, &argv); window = gtk_window_new(GTK_WINDOW_TOPLEVEL); gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER); gtk_window_set_default_size(GTK_WINDOW(window), 280, 200); gtk_window_set_title(GTK_WINDOW(window), "Color Selection Dialog"); vbox = gtk_vbox_new(FALSE, 0); gtk_container_add(GTK_CONTAINER(window), vbox); toolbar = gtk_toolbar_new(); gtk_toolbar_set_style(GTK_TOOLBAR(toolbar), GTK_TOOLBAR_ICONS); gtk_container_set_border_width(GTK_CONTAINER(toolbar), 2); font = gtk_tool_button_new_from_stock(GTK_STOCK_SELECT_COLOR); gtk_toolbar_insert(GTK_TOOLBAR(toolbar), font, -1); gtk_box_pack_start(GTK_BOX(vbox), toolbar, FALSE, FALSE, 5); label = gtk_label_new("ZetCode"); gtk_label_set_justify(GTK_LABEL(label), GTK_JUSTIFY_CENTER); gtk_box_pack_start(GTK_BOX(vbox), label, TRUE, FALSE, 5); g_signal_connect(G_OBJECT(font), "clicked", G_CALLBACK(select_font), label); g_signal_connect_swapped(G_OBJECT(window), "destroy", G_CALLBACK(gtk_main_quit), NULL); gtk_widget_show_all(window); gtk_main(); return 0; }
這個示例與前面的字體選擇對話框非常的類似。不過這裏我們要完成的任務是改變標籤文字的顏色。
GtkWidget *dialog = gtk_color_selection_dialog_new("Font Color"); result = gtk_dialog_run(GTK_DIALOG(dialog));
當然首先是生成一個 GtkColorSelectionDialog
構件。
if (result == GTK_RESPONSE_OK) { GdkColor color; colorsel = GTK_COLOR_SELECTION( GTK_COLOR_SELECTION_DIALOG(dialog)->colorsel); gtk_color_selection_get_current_color(colorsel, &color); gtk_widget_modify_fg(GTK_WIDGET(label), GTK_STATE_NORMAL, &color); }
當我們點擊OK後,我們就得到了相關的顏色設置信息,並我們把這個設置用於改變標籤文字的顏色。