Partial support for #3

ReadMe.md

@@ -15,6 +15,7 @@ A [Zig language](https://ziglang.org/) idiomatic and type-checked bindings for [
 - [Image](docs/image.md)
 - [List](docs/list.md)
 - [Tree](docs/tree.md)
+- [MDI](docs/mdi.md)
 - [Simple notepad (in progress)](docs/simple_notepad.md)
 
 ![Simple Notepad Windows](docs/SimpleNotepadWindows.gif)

docs/mdi.md

@@ -0,0 +1,27 @@
+# IUP for Zig
+[![Lines of code](https://img.shields.io/tokei/lines/github/batiati/IUPforZig)]()
+[![GitHub code size in bytes](https://img.shields.io/github/languages/code-size/batiati/IUPforZig)]()
+[![made with Zig](https://img.shields.io/badge/made%20with%20%E2%9D%A4%20-Zig-orange)]()
+[![made with Zig](https://img.shields.io/badge/unlicensed-public%20domain-brightgreen)]()
+
+## WIP Work in Progress
+
+A [Zig language](https://ziglang.org/) idiomatic and type-checked bindings for [IUP Portable User Interface Toolkit](https://webserver2.tecgraf.puc-rio.br/iup/)
+
+## MDI example
+
+Creates a MDI dialog with multiple children
+
+Source code: [mdi_example.zig](../src/mdi_example.zig).
+
+> Type `zig build mdi` to run this example.
+
+Converted from original example in C
+https://webserver2.tecgraf.puc-rio.br/iup/examples/C/mdi.c
+
+## Screenshots
+
+Windows Classic
+
+![MDI Windows](MdiWindows.gif)
+

src/MainLoop.zig

@@ -6,11 +6,11 @@ const iup = @import("iup.zig");
 /// Global handler for unhandled errors thrown inside callback functions
 pub const ErrorHandlerFn = fn (Element, anyerror) anyerror!void;
 
-const Self = @This();
+const MainLoop = @This();
 const Element = iup.Element;
 
-var exitError: ?anyerror = null;
-var errorHandler: ?ErrorHandlerFn = null;
+var exit_error: ?anyerror = null;
+var error_handler: ?ErrorHandlerFn = null;
 
 ///
 /// Initializes the IUP toolkit. Must be called before any other IUP function.
@@ -21,8 +21,8 @@ pub fn open() iup.Error!void {
 ///
 /// Sets a callback function to handle errors returned inside the main loop
 /// Rethrow the error to terminate the application
-pub fn setErrorHandler(errorHandler: ?ErrorHandlerFn) void {
-    Self.errorHandler = errorHandler;
+pub fn setErrorHandler(value: ?ErrorHandlerFn) void {
+    MainLoop.error_handler = value;
 }
 
 ///
@@ -34,11 +34,11 @@ pub fn exitLoop() void {
 ///
 /// Called by the message loop
 pub fn onError(element: Element, err: anyerror) i32 {
-    if (Self.errorHandler) |func| {
+    if (MainLoop.error_handler) |func| {
         if (func(element, err)) {
             return interop.consts.IUP_DEFAULT;
-        } else |rethrow| {
-            exitError = rethrow;
+        } else |rethrown| {
+            MainLoop.exit_error = rethrown;
         }
     }
 
@@ -60,7 +60,7 @@ pub fn onError(element: Element, err: anyerror) i32 {
 /// causing the IupMainLoop to return. To avoid that set LOCKLOOP=YES before hiding the last dialog.
 pub fn beginLoop() !void {
     interop.beginLoop();
-    if (exitError) |err| return err;
+    if (exit_error) |err| return err;
 }
 
 ///

src/button_example.zig

@@ -43,9 +43,9 @@ fn create_dialog() !*Dialog {
                                 .setTitle("Button with image")
                                 .setName("btn_image")
                                 .setCanFocus(false)
-                                .setImPress(img_press.getHandleName())
-                                .setImage(img_release.getHandleName())
-                                .setIMinActive(img_inactive.getHandleName()) //wrong name!
+                                .setImPress(img_press)
+                                .setImage(img_release)
+                                .setIMinActive(img_inactive) //wrong name!
                                 .setButtonCallback(btn_image_button),
                             Button.init()
                                 .setTitle("on/off")
@@ -133,7 +133,7 @@ const images = struct {
     /// Defines pressed button's image
     pub fn getRelease() !*Image {
         return try (Image.init(16, 16, pixelmap[0..])
-            .setHandleName("img_release")
+            .setHandle("img_release")
             .setColors(1, .{ .r = 215, .g = 215, .b = 215 })
             .setColors(2, .{ .r = 40, .g = 40, .b = 40 })
             .setColors(3, .{ .r = 30, .g = 50, .b = 210 })
@@ -143,7 +143,7 @@ const images = struct {
 
     pub fn getPress() !*Image {
         return try (Image.init(16, 16, pixelmap[0..])
-            .setHandleName("img_press")
+            .setHandle("img_press")
             .setColors(1, .{ .r = 40, .g = 40, .b = 40 })
             .setColors(2, .{ .r = 215, .g = 215, .b = 215 })
             .setColors(3, .{ .r = 0, .g = 20, .b = 180 })
@@ -153,7 +153,7 @@ const images = struct {
 
     pub fn getInactive() !*Image {
         return try (Image.init(16, 16, pixelmap[0..])
-            .setHandleName("img_inactive")
+            .setHandle("img_inactive")
             .setColors(1, .{ .r = 215, .g = 215, .b = 215 })
             .setColors(2, .{ .r = 40, .g = 40, .b = 40 })
             .setColors(3, .{ .r = 100, .g = 100, .b = 100 })

src/commons.zig

@@ -4,6 +4,8 @@ const interop = @import("interop.zig");
 const ascii = std.ascii;
 const testing = std.testing;
 
+pub const NativeType = enum { Void, Control, Canvas, Dialog, Image, Menu, Other };
+
 pub const Error = error{
     ///
     /// Open function must be called before any action
@@ -20,6 +22,10 @@ pub const Error = error{
     ///
     /// Wrong child usage
     InvalidChild,
+
+    ///
+    /// Wrong element usage
+    InvalidElement,
 };
 
 pub const CallbackResult = error{