simple_vision

Overview

simple_vision is a comprehensive GUI toolkit for Eiffel that provides a fluent API for building desktop applications. It wraps EiffelVision2 with modern naming conventions, rich widgets, form validation, state machines, and Cairo graphics.

Part of the Simple Eiffel ecosystem.

Quick Start

Installation

1. Set the environment variable:

   export SIMPLE_EIFFEL=/d/prod

2. Add to your ECF file:

   <library name="simple_vision" location="$SIMPLE_EIFFEL/simple_vision/simple_vision.ecf"/>

Hello World

class
    MY_APP

inherit
    SV_APPLICATION

create
    make_and_launch

feature {NONE} -- Initialization

    make_and_launch
        do
            default_create
            launch
        end

    build_main_window
        local
            sv: SV_QUICK
        do
            create sv.make
            main_window := sv.window ("My App")
                .sized (400, 300)
                .child (
                    sv.column_of (<<
                        sv.text ("Hello, simple_vision!"),
                        sv.button ("Click Me").on_click (agent handle_click)
                    >>)
                    .padding (20)
                    .spacing (10)
                )
        end

    handle_click
        do
            print ("Button clicked!%N")
        end

end

Widget Gallery

Widget Factory (SV_QUICK)

local
    sv: SV_QUICK
do
    create sv.make

    -- Windows
    sv.window ("Title")

    -- Containers
    sv.row                              -- Horizontal box
    sv.column                           -- Vertical box
    sv.row_of (<<widget1, widget2>>)    -- Row with children
    sv.tabs                             -- Tab panel
    sv.horizontal_splitter              -- Left/right split

    -- Basic Widgets
    sv.text ("Label text")
    sv.button ("Click Me")
    sv.text_field
    sv.checkbox ("Enable feature")
    sv.radios (<<"Option 1", "Option 2">>)
    sv.dropdown_with (<<"Choice A", "Choice B">>)

    -- Masked Fields (Phase 6.75)
    sv.phone_field
    sv.email_field
    sv.date_field
    sv.credit_card_field

    -- Dialogs
    sv.info_box ("Information message")
    sv.question_box ("Are you sure?")
    sv.open_file_dialog
    sv.color_picker
end

Form Validation

simple_vision includes a form validation system with built-in rules for common scenarios.

local
    sv: SV_QUICK
    my_form: SV_FORM
do
    create sv.make

    my_form := sv.form
        .add_field (sv.field ("username")
            .widget (sv.text_field)
            .required
            .min_length (3)
            .max_length (20))
        .add_field (sv.field ("email")
            .widget (sv.email_field)
            .required)
        .add_field (sv.field ("age")
            .widget (sv.spin_box_range (18, 120))
            .range (18, 120))
        .on_valid (agent handle_submit)
end

Built-in Validation Rules

State Machines

Declarative UI state management with fluent API and JSON configuration support.

local
    sv: SV_QUICK
    machine: SV_STATE_MACHINE
do
    create sv.make

    -- Create programmatically
    machine := sv.state_machine ("auth")
    machine.state ("logged_out").described_as ("User not logged in").do_nothing
    machine.state ("logging_in").described_as ("Authentication in progress").do_nothing
    machine.state ("logged_in").described_as ("User authenticated").do_nothing

    machine.on ("login").from_state ("logged_out").to ("logging_in").apply.do_nothing
    machine.on ("success").from_state ("logging_in").to ("logged_in").apply.do_nothing
    machine.on ("logout").from_state ("logged_in").to ("logged_out").apply.do_nothing

    machine.set_initial ("logged_out")

    -- Trigger transitions
    machine.trigger ("login")
    print ("Current state: " + machine.current_state.name + "%N")

    -- Or load from JSON file
    if attached sv.state_machine_from_file ("auth.json") as m then
        m.trigger ("login")
    end
end

Theming

Built-in support for dark mode, color schemes, and UI scaling.

local
    sv: SV_QUICK
do
    create sv.make

    -- Dark mode
    sv.set_dark_mode (True)
    sv.toggle_dark_mode

    -- Color schemes
    sv.set_color_scheme ("blue")
    sv.set_color_scheme ("green")
    sv.set_color_scheme ("purple")

    -- UI scaling
    sv.set_ui_scale (1.25)  -- 125%
    sv.increase_ui_scale
    sv.decrease_ui_scale
    sv.reset_ui_scale
end

Cairo Graphics (Phase 7)

Custom drawing with Cairo integration and waveform visualization for audio applications.

local
    sv: SV_QUICK
    canvas: SV_CAIRO_CANVAS
do
    create sv.make

    -- Create drawing canvas
    canvas := sv.canvas (400, 300)
        .background_hex (0xFFFFFF)
        .on_draw (agent draw_content)

    -- Waveform display for audio
    waveform := sv.waveform (300, 100)
        .foreground_hex (0x3498DB)
        .background_hex (0x2C3E50)
end

draw_content (a_context: CAIRO_CONTEXT)
    do
        a_context.set_color_hex (0x3498DB)
            .fill_rect (10, 10, 100, 50)
            .do_nothing
        a_context.set_color_hex (0xE74C3C)
            .stroke_circle (200, 150, 40)
            .do_nothing
    end

API Classes