window

`window()` creates a top-level custom Expr window. Add GUI components with `add()`, optionally attach a `menu()` object, then call `show()`.

A window is a host GUI object. It is shown asynchronously and should normally be kept in a session variable or object property while it is open.

`window` is not cloneable because it represents live host window state and callback state.

Creates a window object.

Default configuration:

Example:

w = window()
    .title('Parameters')
    .size(360, 180)
    .buttons(false, true, true);
 
w.show();

Window properties are read-only. Use methods such as `title()`, `size()`, `position()`, `modal()`, and `buttons()` to change the window.

Example:

w = window().title('Probe').size(300, 160);
print(w.title, ' ', w.size_width, ' x ', w.size_height);

`clone()` is not supported for `window`.

Sets the window title.

Example:

w = window().title('Tool Setup');

Sets the window size in pixels. Width and height are clamped to at least `1`.

Example:

w = window().size(420, 240);

Sets the top-left window position in pixels. `-1, -1` lets the host choose the position.

Example:

w = window().position(100, 80);

Enables or disables the built-in Apply, OK, and Close buttons.

Example:

w = window().buttons(true, true, true);

Sets whether the window is modal. With this form, taskbar visibility is chosen automatically: non-modal windows are shown in the taskbar, modal windows are not.

Example:

w = window().modal(false);

Sets modal state and taskbar visibility explicitly.

Example:

w = window().modal(false, true);

Enables or disables user resizing.

Example:

w = window().resizable(false);

Adds a GUI component to the window content area. A component can belong to only one window.

Example:

w = window().title('Input').size(300, 140);
w.add(label().position(20, 20).size(180, 24).text('Name'));
w.add(textinput().position(20, 48).size(220, 24).text('Part 1'));
w.show();

Attaches a `menu()` object to the window.

Example:

function on_open()
{
    print('Open');
}
 
m = menu();
file = m.add('File');
file.add('Open', on_open);
 
w = window().menu(m).show();

Shows the window asynchronously and returns the window object immediately. Calling `show()` again after the window was closed creates and shows the live host window again.

Example:

w = window().title('Status').size(280, 120);
w.show();

Requests the Close action. This follows the same request flow as `request_close()`, so an `on_request()` callback can veto the close by returning `false`.

Example:

w.close();

Returns whether the live host window currently exists and is visible.

Example:

if (w.is_visible())
{
    print('Window is open');
}

Simulates clicking the visible built-in Apply button. If the Apply button is not available or disabled, no action is performed.

Simulates clicking the visible built-in OK button. If the OK button is not available or disabled, no action is performed.

Simulates clicking the visible built-in Close button. If the Close button is not available or disabled, no action is performed.

Runs the Apply request flow even if the Apply button is not visible. This calls `on_request(2)` but does not close the window.

Runs the OK request flow even if the OK button is not visible. This calls `on_request(1)`. If the request is allowed, the window closes and `on_closed(1)` is called.

Runs the Close request flow even if the Close button is not visible. This calls `on_request(0)`. If the request is allowed, the window closes and `on_closed(0)` is called.

Sets a callback that is called when the live window is shown.

Sets a callback that is called when Apply, OK, or Close is requested.

For OK and Close requests, return `false` to keep the window open. Return `true` or return no value to allow the close. For Apply requests, the return value is ignored because Apply does not close the window.

Result codes:

Sets a callback that is called after the window closes.

Result codes are the same as for `on_request()`.

Sets a callback that is called after the window content area is resized.

The callback receives content-area bounds, not the outer operating-system window frame.

class Demo()
{
    request_count = 0;
    closed_count = 0;
    last_code = -1;
    wnd = none();
 
    function on_request(code)
    {
        request_count = request_count + 1;
        last_code = code;
 
        // Veto the first close attempt.
        if (code == 0 && request_count == 1)
        {
            return false;
        }
 
        return true;
    }
 
    function on_closed(code)
    {
        closed_count = closed_count + 1;
        last_code = code;
    }
 
    function show()
    {
        wnd = window()
            .title('Demo')
            .size(300, 160)
            .buttons(false, true, true)
            .on_request(this.on_request)
            .on_closed(this.on_closed);
 
        wnd.add(label().position(20, 20).size(220, 24).text('Custom window'));
        wnd.show();
    }
}
 
demo = Demo();
demo.show();

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