Add set_decorations method to Window (#365)

This has been stubbed on all platforms other than X11. The X11 implementation has also been
revised to toggle correctly, as it was previously only able to remove decorations.

CHANGELOG.md

@@ -3,6 +3,7 @@
 - Add support for `Touch` for emscripten backend.
 - Added support for `DroppedFile`, `HoveredFile`, and `HoveredFileCancelled` to X11 backend.
 - **Breaking:** `unix::WindowExt` no longer returns pointers for things that aren't actually pointers; `get_xlib_window` now returns `Option<std::os::raw::c_ulong>` and `get_xlib_screen_id` returns `Option<std::os::raw::c_int>`. Additionally, methods that previously returned `libc::c_void` have been changed to return `std::os::raw::c_void`, which are not interchangeable types, so users wanting the former will need to explicitly cast.
+- Added `set_decorations` method to `Window` to allow decorations to be toggled after the window is built. Presently only implemented on X11.
 
 # Version 0.9.0 (2017-12-01)
 

src/platform/android/mod.rs

@@ -44,7 +44,7 @@ impl EventsLoop {
         MonitorId
     }
 
-  
+
     pub fn poll_events<F>(&mut self, mut callback: F)
         where F: FnMut(::Event)
     {
@@ -101,7 +101,7 @@ impl EventsLoop {
                     None
                 }
             };
-            
+
             if let Some(event) = e {
                 callback(event);
             }
@@ -288,6 +288,11 @@ impl Window {
         // Android has single screen maximized apps so nothing to do
     }
 
+    #[inline]
+    pub fn set_decorations(&self, _decorations: bool) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         RootMonitorId{inner: MonitorId}

src/platform/emscripten/mod.rs

@@ -517,6 +517,11 @@ impl Window {
         // iOS has single screen maximized apps so nothing to do
     }
 
+    #[inline]
+    pub fn set_decorations(&self, _decorations: bool) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> ::MonitorId {
         ::MonitorId{inner: MonitorId}
@@ -693,7 +698,7 @@ fn key_translate_virt(input: [ffi::EM_UTF8; ffi::EM_HTML5_SHORT_STRING_LEN_BYTES
         "PreviousCandidate" => None,
         "Process" => None,
         "SingleCandidate" => None,
-        
+
         "HangulMode" => None,
         "HanjaMode" => None,
         "JunjaMode" => None,

src/platform/ios/mod.rs

@@ -354,6 +354,11 @@ impl Window {
         // iOS has single screen maximized apps so nothing to do
     }
 
+    #[inline]
+    pub fn set_decorations(&self, _decorations: bool) {
+        // N/A
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         RootMonitorId{inner: MonitorId}

src/platform/linux/mod.rs

@@ -248,7 +248,9 @@ impl Window {
     pub fn set_maximized(&self, maximized: bool) {
         match self {
             &Window::X(ref w) => w.set_maximized(maximized),
-            &Window::Wayland(ref _w) => {},
+            &Window::Wayland(ref _w) => {
+                unimplemented!();
+            }
         }
     }
 
@@ -256,7 +258,19 @@ impl Window {
     pub fn set_fullscreen(&self, monitor: Option<RootMonitorId>) {
         match self {
             &Window::X(ref w) => w.set_fullscreen(monitor),
-            &Window::Wayland(ref _w) => {},
+            &Window::Wayland(ref _w) => {
+                unimplemented!();
+            }
+        }
+    }
+
+    #[inline]
+    pub fn set_decorations(&self, decorations: bool) {
+        match self {
+            &Window::X(ref w) => w.set_decorations(decorations),
+            &Window::Wayland(ref _w) => {
+                unimplemented!();
+            }
         }
     }
 

src/platform/linux/x11/window.rs

@@ -432,40 +432,36 @@ impl Window2 {
     pub fn set_decorations(&self, decorations: bool) {
         #[repr(C)]
         struct MotifWindowHints {
-            flags: u32,
-            functions: u32,
-            decorations: u32,
-            input_mode: i32,
-            status: u32,
+            flags: c_ulong,
+            functions: c_ulong,
+            decorations: c_ulong,
+            input_mode: c_long,
+            status: c_ulong,
         }
 
-        let wm_hints = unsafe {
-            (self.x.display.xlib.XInternAtom)(self.x.display.display, b"_MOTIF_WM_HINTS\0".as_ptr() as *const _, 0)
+        let wm_hints = unsafe { util::get_atom(&self.x.display, b"_MOTIF_WM_HINTS\0") }
+            .expect("Failed to call XInternAtom (_MOTIF_WM_HINTS)");
+
+        let hints = MotifWindowHints {
+            flags: 2, // MWM_HINTS_DECORATIONS
+            functions: 0,
+            decorations: decorations as _,
+            input_mode: 0,
+            status: 0,
         };
-        self.x.display.check_errors().expect("Failed to call XInternAtom");
 
-        if !decorations {
-            let hints = MotifWindowHints {
-                flags: 2, // MWM_HINTS_DECORATIONS
-                functions: 0,
-                decorations: 0,
-                input_mode: 0,
-                status: 0,
-            };
-
-            unsafe {
-                (self.x.display.xlib.XChangeProperty)(
-                    self.x.display.display, self.x.window,
-                    wm_hints, wm_hints, 32 /* Size of elements in struct */,
-                    ffi::PropModeReplace, &hints as *const MotifWindowHints as *const u8,
-                    5 /* Number of elements in struct */);
-                (self.x.display.xlib.XFlush)(self.x.display.display);
-            }
-        } else {
-            unsafe {
-                (self.x.display.xlib.XDeleteProperty)(self.x.display.display, self.x.window, wm_hints);
-                (self.x.display.xlib.XFlush)(self.x.display.display);
-            }
+        unsafe {
+            (self.x.display.xlib.XChangeProperty)(
+                self.x.display.display,
+                self.x.window,
+                wm_hints,
+                wm_hints,
+                32, // struct members are longs
+                ffi::PropModeReplace,
+                &hints as *const _ as *const u8,
+                5 // struct has 5 members
+            );
+            (self.x.display.xlib.XFlush)(self.x.display.display);
         }
 
         self.x.display.check_errors().expect("Failed to set decorations");

src/platform/macos/window.rs

@@ -643,6 +643,11 @@ impl Window2 {
         unimplemented!()
     }
 
+    #[inline]
+    pub fn set_decorations(&self, _decorations: bool) {
+        unimplemented!()
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         unimplemented!()

src/platform/windows/window.rs

@@ -45,7 +45,7 @@ impl Window {
     {
         let mut w_attr = Some(w_attr.clone());
         let mut pl_attr = Some(pl_attr.clone());
-        
+
         let (tx, rx) = channel();
 
         events_loop.execute_in_thread(move |inserter| {
@@ -288,6 +288,11 @@ impl Window {
         unimplemented!()
     }
 
+    #[inline]
+    pub fn set_decorations(&self, _decorations: bool) {
+        unimplemented!()
+    }
+
     #[inline]
     pub fn get_current_monitor(&self) -> RootMonitorId {
         unimplemented!()
@@ -298,7 +303,7 @@ impl Drop for Window {
     #[inline]
     fn drop(&mut self) {
         unsafe {
-            // We are sending WM_CLOSE, and our callback will process this by calling DefWindowProcW, 
+            // We are sending WM_CLOSE, and our callback will process this by calling DefWindowProcW,
             // which in turn will send a WM_DESTROY.
             user32::PostMessageW(self.window.0, winapi::WM_CLOSE, 0, 0);
         }

src/window.rs

@@ -313,6 +313,12 @@ impl Window {
         self.window.set_fullscreen(monitor)
     }
 
+    /// Turn window decorations on or off.
+    #[inline]
+    pub fn set_decorations(&self, decorations: bool) {
+        self.window.set_decorations(decorations)
+    }
+
     /// Returns the current monitor the window is on or the primary monitor is nothing
     /// matches
     pub fn get_current_monitor(&self) -> MonitorId {