Add maximized property to NativeOptions (#649)

egui_glium/src/backend.rs

@@ -83,6 +83,7 @@ fn create_display(
 ) -> glium::Display {
     let mut window_builder = glutin::window::WindowBuilder::new()
         .with_always_on_top(native_options.always_on_top)
+        .with_maximized(native_options.maximized)
         .with_decorations(native_options.decorated)
         .with_resizable(native_options.resizable)
         .with_title(app.name())

epi/src/lib.rs

@@ -163,6 +163,9 @@ pub struct NativeOptions {
     /// Sets whether or not the window will always be on top of other windows.
     pub always_on_top: bool,
 
+    /// Show window in maximized mode
+    pub maximized: bool,
+
     /// On desktop: add window decorations (i.e. a frame around your app)?
     /// If false it will be difficult to move and resize the app.
     pub decorated: bool,
@@ -191,6 +194,7 @@ impl Default for NativeOptions {
     fn default() -> Self {
         Self {
             always_on_top: false,
+            maximized: false,
             decorated: true,
             drag_and_drop_support: false,
             icon_data: None,