use php\swing\UIForm;
    use php\swing\UIEditorArea;
    use php\swing\UIButton;
    use php\io\Stream;
    use php\io\FileStream;
    use php\lang\System;

    $form = new UIForm();
    $form->size = [550, 600];
    $form->title = 'Stream::getContents';
    $form->moveToCenter();

    $form->on('windowClosing', function(){
       System::halt(0);
    });

    $u = new UIEditorArea();
    $u->size = [450, 450];
    $u->position = [40, 20];
    $u->contentType = "text/html";
    $u->text = "";
    $form->add($u);

    $button = new UIButton();
    $button->size = [100, 30];
    $button->position = [200, 500];
    $button->text = 'OK!';
    $button->on('click', function() use ($u) {
    $u->text = Stream::getContents('http://community.develstudio.ru/forum.php');
    });
    $form->add($button);

    $form->visible = true;