Ruby栏目

[翻译]Ruby GTK教程5——对话框

对话框

在这部分的Ruby GTK教程我们将介绍对话框。


对话框是现代GUI应用程序不可缺的一部分。对话是两个或者更多人之间交谈。在计算机程序中对话是一个用于与应用程序交互的窗口。对话框用于输入数据、修改数据、修改设置等。对话框在用户与计算机程序之间的交流具有重要意义。


消息盒子


消息对话框是应用程序便于给用户提供消息的对话框。消息由文本和图片数据组成。


#!/usr/bin/ruby

# ZetCode Ruby GTK tutorial
#
# This example shows message
# dialogs
#
# author: jan bodnar
# website: www.zetcode.com
# last modified: June 2009

require ‘gtk2’


class RubyApp < Gtk::Window

    def initialize
        super

        set_title “Messages”
        signal_connect “destroy” do
            Gtk.main_quit
        end

        init_ui

        set_default_size 250, 100
        set_window_position Gtk::Window::POS_CENTER

        show_all
    end

    def init_ui

        table = Gtk::Table.new 2, 2, true

        info = Gtk::Button.new “Information”
        warn = Gtk::Button.new “Warning”
        ques = Gtk::Button.new “Question”
        erro = Gtk::Button.new “Error”

        info.signal_connect “clicked” do
            on_info
        end

        warn.signal_connect “clicked” do
            on_warn
        end

        ques.signal_connect “clicked” do
            on_ques
        end

        erro.signal_connect “clicked” do
            on_erro
        end

        table.attach info, 0, 1, 0, 1
        table.attach warn, 1, 2, 0, 1
        table.attach ques, 0, 1, 1, 2
        table.attach erro, 1, 2, 1, 2

        add table

    end

    def on_info
        md = Gtk::MessageDialog.new(self,
            Gtk::Dialog::DESTROY_WITH_PARENT, Gtk::MessageDialog::INFO,
            Gtk::MessageDialog::BUTTONS_CLOSE, “Download completed”)
        md.run
        md.destroy
    end


    def on_erro
        md = Gtk::MessageDialog.new(self, Gtk::Dialog::MODAL |
            Gtk::Dialog::DESTROY_WITH_PARENT, Gtk::MessageDialog::ERROR,
            Gtk::MessageDialog::BUTTONS_CLOSE, “Error loading file”)
        md.run
        md.destroy
    end


    def on_ques
        md = Gtk::MessageDialog.new(self,
            Gtk::Dialog::DESTROY_WITH_PARENT, Gtk::MessageDialog::QUESTION,
            Gtk::MessageDialog::BUTTONS_CLOSE, “Are you sure to quit?”)
        md.run
        md.destroy
    end

    def on_warn
        md = Gtk::MessageDialog.new(self,
            Gtk::Dialog::DESTROY_WITH_PARENT, Gtk::MessageDialog::WARNING,
            Gtk::MessageDialog::BUTTONS_CLOSE, “Unallowed operation”)
        md.run
        md.destroy
    end
end

Gtk.init
    window = RubyApp.new
Gtk.main

我们的例子中显示了四种消息对话框。信息、警告、询问和错误消息对话框。


info = Gtk::Button.new “Information”
warn = Gtk::Button.new “Warning”
ques = Gtk::Button.new “Question”
erro = Gtk::Button.new “Error”

创建四个按钮。每个按钮将显示不同种类的消息对话框。


def on_info
    md = Gtk::MessageDialog.new(self,
        Gtk::Dialog::DESTROY_WITH_PARENT, Gtk::MessageDialog::INFO,
        Gtk::MessageDialog::BUTTONS_CLOSE, “Download completed”)
    md.run
    md.destroy
end

如果我们点击了info按钮，信息对话框将显示。Gtk::MessageDialog::INFO指定了对话框的类型。Gtk::MessageDialog::BUTTONS_CLOSE指定在对话框中显示的按钮。最后一个参数是要显示的消息。对话框使用run方法显示。程序员必须也要调用destroy或者hide方法。

image1 image2

image3 image4


关于对话框(AboutDialog)


关于对话框显示了应用程序的信息。关于对话框可以显示logo、应用程序名、版本号、版权、网站或者授权信息。它也可能给出作者、文档编写才、翻译者和设计师的信息。


#!/usr/bin/ruby

# ZetCode Ruby GTK tutorial
#
# This example demonstrates the
# AboutDialog dialog
#
# author: jan bodnar
# website: www.zetcode.com
# last modified: June 2009

require ‘gtk2’


class RubyApp < Gtk::Window

    def initialize
        super

        set_title “About dialog”
        signal_connect “destroy” do
            Gtk.main_quit
        end

        init_ui

        set_default_size 300, 150
        set_window_position Gtk::Window::POS_CENTER

        show_all
    end

    def init_ui

        button = Gtk::Button.new “About”
        button.set_size_request 80, 30

        button.signal_connect “clicked” do
            on_clicked
        end

        fix = Gtk::Fixed.new
        fix.put button, 20, 20

        add fix

    end

    def on_clicked
        about = Gtk::AboutDialog.new
        about.set_program_name “Battery”
        about.set_version “0.1”
        about.set_copyright “(c) Jan Bodnar”
        about.set_comments “Battery is a simple tool for battery checking”
        about.set_website “http://www.zetcode.com“
        about.set_logo Gdk::Pixbuf.new “battery.png”
        about.run
        about.destroy
    end
end

Gtk.init
    window = RubyApp.new
Gtk.main

代码伅使用了AboutDialog的一些特性。


about = Gtk::AboutDialog.new

创建一个AboutDialog。


about.set_program_name “Battery”
about.set_version “0.1”
about.set_copyright “(c) Jan Bodnar”

这里我们指定名称、版本号和版权信息。


about.set_logo Gdk::Pixbuf.new “battery.png”

这行创建一个logo。

image5

图片：AboutDialog


字体选择对话框


FontSelectionDialog是一个用于选择字体的对话框。它典型的应用于文本编辑或者格式化的应用程序中。


#!/usr/bin/ruby

# ZetCode Ruby GTK tutorial
#
# This example works with the
# FontSelectionDialog
#
# author: jan bodnar
# website: www.zetcode.com
# last modified: June 2009

require ‘gtk2’


class RubyApp < Gtk::Window

    def initialize
        super

        set_title “FontSelectionDialog”
        signal_connect “destroy” do
            Gtk.main_quit
        end

        init_ui

        set_default_size 300, 150
        set_window_position Gtk::Window::POS_CENTER

        show_all
    end

    def init_ui

        set_border_width 10
        @label = Gtk::Label.new “The only victory over love is flight.”
        button = Gtk::Button.new “Select font”

        button.signal_connect “clicked” do
            on_clicked
        end

        fix = Gtk::Fixed.new
        fix.put button, 100, 30
        fix.put @label, 30, 90
        add fix

    end

    def on_clicked
        fdia = Gtk::FontSelectionDialog.new “Select font name”
        response = fdia.run

        if response == Gtk::Dialog::RESPONSE_OK
            font_desc = Pango::FontDescription.new fdia.font_name
            if font_desc
                @label.modify_font font_desc
            end
        end
        fdia.destroy
    end
end

Gtk.init
    window = RubyApp.new
Gtk.main

这个代码例子我们创建了一个按钮和一个标签。点击按钮之后显示字体选择对话框。


fdia = Gtk::FontSelectionDialog.new “Select font name”

创建FontSelectionDialog。


if response == Gtk::Dialog::RESPONSE_OK
    font_desc = Pango::FontDescription.new fdia.font_name
    if font_desc
        @label.modify_font font_desc
    end
end

如果点击确定按钮，标签的字体会变为我们在对话框中选中的。

image6

图片：FontSelectionDialog


颜色选择对话框


ColorSelectionDialog是用于选择颜色的对话框。


#!/usr/bin/ruby

# ZetCode Ruby GTK tutorial
#
# This example works with the
# ColorSelectionDialog
#
# author: jan bodnar
# website: www.zetcode.com
# last modified: June 2009

require ‘gtk2’


class RubyApp < Gtk::Window

    def initialize
        super

        set_title “ColorSelectionDialog”
        signal_connect “destroy” do
            Gtk.main_quit
        end

        init_ui

        set_default_size 350, 150
        set_window_position Gtk::Window::POS_CENTER

        show_all
    end

    def init_ui

        set_border_width 10
        @label = Gtk::Label.new “The only victory over love is flight.”
        button = Gtk::Button.new “Select color”

        button.signal_connect “clicked” do
            on_clicked
        end

        fix = Gtk::Fixed.new
        fix.put button, 100, 30
        fix.put @label, 30, 90
        add fix
    end

    def on_clicked
        cdia = Gtk::ColorSelectionDialog.new “Select color”
        response = cdia.run

        if response == Gtk::Dialog::RESPONSE_OK
            colorsel = cdia.colorsel
            color = colorsel.current_color
            @label.modify_fg Gtk::STATE_NORMAL, color
        end

        cdia.destroy
    end
end

Gtk.init
    window = RubyApp.new
Gtk.main

这个例子与前一个例子很相似。这次我们是改变标签的颜色。


cdia = Gtk::ColorSelectionDialog.new “Select color”

创建ColorSelectionDialog。


if response == Gtk::Dialog::RESPONSE_OK
    colorsel = cdia.colorsel
    color = colorsel.current_color
    @label.modify_fg Gtk::STATE_NORMAL, color
end

如果按下OK按钮，我们得到颜色值并修改标签的颜色。


image7

图片：ColorSelectionDialog


这部分的Ruby GTK教程我们展示了对话框。



原文地址： http://zetcode.com/gui/rubygtk/dialogs/

翻译：龙昌 admin@longchangjin.cn