Native desktop applications with PHP

Currently the only way to set the icon is to call directly the protected method setWm. If we don't want to follow the approach of extending MainWindow we should still be able to set its icon.

This PR addresses that concern, making public a setIcon method that receives the path for the icon bitmap file. As it was added to the docblock, / should be used as directory separator even on Windows. When trying to use \ I received the following error:

PHP Fatal error:  Uncaught Tkui\TclTk\Exceptions\EvalException: Eval: bitmap "C:WindowsSystem32OneDrive.ico" not defined in C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Tcl.php:63
Stack trace:
#0 C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Interp.php(54): Tkui\TclTk\Tcl->eval(Object(Tkui\TclTk\Interp), 'wm iconbitmap ....')
#1 C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\TkApplication.php(86): Tkui\TclTk\Interp->eval('wm iconbitmap ....')
#2 C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\TkWindowManager.php(209): Tkui\TclTk\TkApplication->tclEval('wm', 'iconbitmap', '.', 'C:\\Windows\\Syst...')
#3 C:\Users\carlo\Documents\code\untitled\index.php(38): Tkui\TclTk\TkWindowManager->setWm('iconbitmap', 'C:\\Windows\\Syst...')
#4 {main}
  thrown in C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Tcl.php on line 63

Fatal error: Uncaught Tkui\TclTk\Exceptions\EvalException: Eval: bitmap "C:WindowsSystem32OneDrive.ico" not defined in C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Tcl.php on line 63

Tkui\TclTk\Exceptions\EvalException: Eval: bitmap "C:WindowsSystem32OneDrive.ico" not defined in C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Tcl.php on line 63

Call Stack:
    0.0002     412616   1. {main}() C:\Users\carlo\Documents\code\untitled\index.php:0
    0.1035     887664   2. Tkui\TclTk\TkWindowManager->setWm($command = 'iconbitmap', ...$value = variadic('C:\\Windows\\System32\\OneDrive.ico')) C:\Users\carlo\Documents\code\untitled\index.php:38
    0.1035     888040   3. Tkui\TclTk\TkApplication->tclEval(...$args = variadic('wm', 'iconbitmap', '.', 'C:\\Windows\\System32\\OneDrive.ico')) C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\TkWindowManager.php:209
    0.1035     888496   4. Tkui\TclTk\Interp->eval($script = 'wm iconbitmap . C:\\Windows\\System32\\OneDrive.ico') C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\TkApplication.php:86
    0.1035     888496   5. Tkui\TclTk\Tcl->eval($interp = class Tkui\TclTk\Interp { private Tkui\TclTk\Tcl $tcl = class Tkui\TclTk\Tcl { private FFI $ffi = class FFI { ... } }; private FFI\CData $interp = class FFI\CData { public $0 = class FFI\CData { ... } }; private ?Psr\Log\LoggerInterface $logger = NULL }, $script = 'wm iconbitmap . C:\\Windows\\System32\\OneDrive.ico') C:\Users\carlo\Documents\code\untitled\vendor\skoro\tkui\src\TclTk\Interp.php:54

Instead of the application name there is only Tk in Gnome desktop environment:

In Gnome DE the application class name should be used. It can be checked by running wish with -name parameter like this:

wish some-script.tcl
wish -name ScriptApp some-script.tcl

Also, digging into tk sources there is toplevel initialization with -class option (tkWindow.c:3314-3322):

    /*
     * Create an argument list for creating the top-level window, using the
     * information parsed from argv, if any.
     */

    cmd = Tcl_NewStringObj("toplevel . -class", -1);

    Tcl_ListObjAppendElement(NULL, cmd, classObj);
    classObj = NULL;

Since the root toplevel is created by Tk initialization routine we need to provide name through Tcl argv global variable.

Now an application name or class can be used in some desktop environments like Gnome where the app name is shown in the Dash to Dock and the top panel but window title in the application switcher. There is also an option to override the app name via .env and APP_NAME parameter but it cannot be overridden like this:

APP_NAME=SomeApp php demos/buttons.php

This is due to usage m1/env package which is cannot read the os environment. As a solution, transition to dotenv could fix that.

PS: not the app name can be overridden but any .env parameter, it will let to override an app theme from the command like this: THEME=dark php app.php

This PR adds Tcl list variables. It supports adding, getting values and get count of elements. Usage is following:

$argv = $interp->createListVariable('argv');
$argv->append('-name', 'value1');

buttons, menu, text, treeview demos are not working with PHP 7.4 which is minimal requirement in composer.json. This PR removes all the PHP 8 new feature to be compatible with 7.4 Mentioned here: https://github.com/skoro/php-tkui/issues/4#issuecomment-1294352704

Since php-gui is already existing this package could be treated as a fork of it but it's not so. This transition changes the package name to tkui and namespaces. The repository should also be renamed.

This is especially actual for Windows users who needs to install TclTk separately by using one of available distribution. Including tcltk will be much simpler for getting started with the package.

What should be done:

• make tcltk compilation script (I manually tried msys2 for compiling and it works but it should be automated)
• strip unneeded files from tcltk to reduce distribution size (demo, help, etc)
• make os detection before app bootstrapping to pickup the included distribution depending on os

Disadvantages:

• the package size will be increased (+ ~10mb)

APP_ICON in .env could be used for overriding the application icon.

Use cases: ?

Problems:

• how to add more than one icon for different resolutions ?

Using PHP8 gives the following improvements:

• nullsafe operator ?-> (HasLogger)
• constructor property promotions
• using Enums instead of consts
• union types: array|Options in widget constructors