Label
Labels are the main method of placing non-editable text in windows, for instance to place a title next to a Entry widget. You can specify the text in the constructor, or later with the set_text() or set_markup() methods.
The width of the label will be adjusted automatically. You can produce multi-line labels by putting line breaks ("\n") in the label string.
The label text can be justified using the set_justify() method. The widget is also capable of word-wrapping, which can be activated with set_line_wrap().
Gtk::Label support some simple formatting, for instance allowing you to make some text bold, colored, or larger. You can do this by providing a string to set_markup(), using the Pango Markup syntax. For instance, <b>bold text</b> and <s>strikethrough text</s> .
- 7.1.1. Example
7.1.1. Example
Below is a short example to illustrate these functions. This example makes use of the Frame widget to better demonstrate the label styles. (The Frame widget is explained in the Frame section.)
File: examplewindow.h (For use with gtkmm 3, not gtkmm 2)
#ifndef GTKMM_EXAMPLEWINDOW_H #define GTKMM_EXAMPLEWINDOW_H #include <gtkmm.h> class ExampleWindow : public Gtk::Window { public: ExampleWindow(); virtual ~ExampleWindow(); protected: //Child widgets: Gtk::HBox m_HBox; Gtk::VBox m_VBox, m_VBox2; Gtk::Frame m_Frame_Normal, m_Frame_Multi, m_Frame_Left, m_Frame_Right, m_Frame_LineWrapped, m_Frame_FilledWrapped, m_Frame_Underlined; Gtk::Label m_Label_Normal, m_Label_Multi, m_Label_Left, m_Label_Right, m_Label_LineWrapped, m_Label_FilledWrapped, m_Label_Underlined; }; #endif //GTKMM_EXAMPLEWINDOW_H
File: examplewindow.cc (For use with gtkmm 3, not gtkmm 2)
#include "examplewindow.h" #include <iostream> ExampleWindow::ExampleWindow() : m_HBox(false, 5), m_VBox(false, 5), m_Frame_Normal("Normal Label"), m_Frame_Multi("Multi-line Label"), m_Frame_Left("Left Justified Label"), m_Frame_Right("Right Justified Label"), m_Frame_LineWrapped("Line wrapped label"), m_Frame_FilledWrapped("Filled, wrapped label"), m_Frame_Underlined("Underlined label"), m_Label_Normal("_This is a Normal label", true), m_Label_Multi("This is a Multi-line label.\nSecond line\nThird line"), m_Label_Left("This is a Left-Justified\nMulti-line label.\nThird line"), m_Label_Right("This is a Right-Justified\n" "Multi-line label.\nFourth line, (j/k)"), m_Label_Underlined("This label is underlined!\n" "This one is underlined in quite a funky fashion") { set_title("Label"); set_border_width(5); add(m_HBox); m_HBox.pack_start(m_VBox, Gtk::PACK_SHRINK); m_Frame_Normal.add(m_Label_Normal); m_VBox.pack_start(m_Frame_Normal, Gtk::PACK_SHRINK); m_Frame_Multi.add(m_Label_Multi); m_VBox.pack_start(m_Frame_Multi, Gtk::PACK_SHRINK); m_Label_Left.set_justify(Gtk::JUSTIFY_LEFT); m_Frame_Left.add(m_Label_Left); m_VBox.pack_start(m_Frame_Left, Gtk::PACK_SHRINK); m_Label_Right.set_justify(Gtk::JUSTIFY_RIGHT); m_Frame_Right.add(m_Label_Right); m_VBox.pack_start(m_Frame_Right, Gtk::PACK_SHRINK); m_HBox.pack_start(m_VBox2, Gtk::PACK_SHRINK); m_Label_LineWrapped.set_text( "This is an example of a line-wrapped label. It " \ /* add a big space to the next line to test spacing */ \ "should not be taking up the entire " "width allocated to it, but automatically " \ "wraps the words to fit. " \ "The time has come, for all good men, to come to " \ "the aid of their party. " \ "The sixth sheik's six sheep's sick.\n" \ " It supports multiple paragraphs correctly, " \ "and correctly adds " \ "many extra spaces. "); m_Label_LineWrapped.set_line_wrap(); m_Frame_LineWrapped.add(m_Label_LineWrapped); m_VBox2.pack_start(m_Frame_LineWrapped, Gtk::PACK_SHRINK); m_Label_FilledWrapped.set_text( "This is an example of a line-wrapped, filled label. " \ "It should be taking " \ "up the entire width allocated to it. " \ "Here is a sentence to prove " \ "my point. Here is another sentence. " \ "Here comes the sun, do de do de do.\n" \ " This is a new paragraph.\n" \ " This is another newer, longer, better " \ "paragraph. It is coming to an end, " \ "unfortunately."); m_Label_FilledWrapped.set_justify(Gtk::JUSTIFY_FILL); m_Label_FilledWrapped.set_line_wrap(); m_Frame_FilledWrapped.add(m_Label_FilledWrapped); m_VBox2.pack_start(m_Frame_FilledWrapped, Gtk::PACK_SHRINK); m_Label_Underlined.set_justify(Gtk::JUSTIFY_LEFT); m_Label_Underlined.set_pattern ( "_________________________ _ _________ _ ______" " __ _______ ___"); m_Frame_Underlined.add(m_Label_Underlined); m_VBox2.pack_start(m_Frame_Underlined, Gtk::PACK_SHRINK); show_all_children(); } ExampleWindow::~ExampleWindow() { }
File: main.cc (For use with gtkmm 3, not gtkmm 2)
#include "examplewindow.h" #include <gtkmm/main.h> int main(int argc, char *argv[]) { Gtk::Main kit(argc, argv); ExampleWindow window; //Shows the window and returns when it is closed. Gtk::Main::run(window); return 0; }