Merge pull request #8047 from electron/fix-incorrect-window-size

Fix incorrect window size after restore on Windows

atom/browser/native_window_views.cc

@@ -327,6 +327,7 @@ NativeWindowViews::NativeWindowViews(
     last_window_state_ = ui::SHOW_STATE_FULLSCREEN;
   else
     last_window_state_ = ui::SHOW_STATE_NORMAL;
+  last_normal_bounds_ = GetBounds();
 #endif
 }
 

atom/browser/native_window_views.h

@@ -211,6 +211,23 @@ class NativeWindowViews : public NativeWindow,
 
   ui::WindowShowState last_window_state_;
 
+  // There's an issue with restore on Windows, that sometimes causes the Window
+  // to receive the wrong size (#2498). To circumvent that, we keep tabs on the
+  // size of the window while in the normal state (not maximized, minimized or
+  // fullscreen), so we restore it correctly.
+  gfx::Rect last_normal_bounds_;
+  gfx::Rect last_normal_bounds_before_move_;
+
+  // last_normal_bounds_ may or may not require update on WM_MOVE. When a
+  // window is maximized, it is moved (WM_MOVE) to maximum size first and then
+  // sized (WM_SIZE). In this case, last_normal_bounds_ should not update. We
+  // keep last_normal_bounds_candidate_ as a candidate which will become valid
+  // last_normal_bounds_ if the moves are consecutive with no WM_SIZE event in
+  // between.
+  gfx::Rect last_normal_bounds_candidate_;
+
+  bool consecutive_moves_;
+
   // In charge of running taskbar related APIs.
   TaskbarHost taskbar_host_;
 

atom/browser/native_window_views_win.cc

@@ -127,6 +127,10 @@ bool NativeWindowViews::PreHandleMSG(
     case WM_SIZE: {
       // Handle window state change.
       HandleSizeEvent(w_param, l_param);
+
+      consecutive_moves_ = false;
+      last_normal_bounds_before_move_ = last_normal_bounds_;
+
       return false;
     }
     case WM_MOVING: {
@@ -134,6 +138,15 @@ bool NativeWindowViews::PreHandleMSG(
         ::GetWindowRect(GetAcceleratedWidget(), (LPRECT)l_param);
       return false;
     }
+    case WM_MOVE: {
+      if (last_window_state_ == ui::SHOW_STATE_NORMAL) {
+        if (consecutive_moves_)
+          last_normal_bounds_ = last_normal_bounds_candidate_;
+        last_normal_bounds_candidate_ = GetBounds();
+        consecutive_moves_ = true;
+      }
+      return false;
+    }
     default:
       return false;
   }
@@ -145,6 +158,9 @@ void NativeWindowViews::HandleSizeEvent(WPARAM w_param, LPARAM l_param) {
   switch (w_param) {
     case SIZE_MAXIMIZED:
       last_window_state_ = ui::SHOW_STATE_MAXIMIZED;
+      if (consecutive_moves_) {
+        last_normal_bounds_ = last_normal_bounds_before_move_;
+      }
       NotifyWindowMaximize();
       break;
     case SIZE_MINIMIZED:
@@ -152,20 +168,35 @@ void NativeWindowViews::HandleSizeEvent(WPARAM w_param, LPARAM l_param) {
       NotifyWindowMinimize();
       break;
     case SIZE_RESTORED:
-      switch (last_window_state_) {
-        case ui::SHOW_STATE_MAXIMIZED:
-          last_window_state_ = ui::SHOW_STATE_NORMAL;
-          NotifyWindowUnmaximize();
-          break;
-        case ui::SHOW_STATE_MINIMIZED:
-          if (IsFullscreen()) {
-            last_window_state_ = ui::SHOW_STATE_FULLSCREEN;
-            NotifyWindowEnterFullScreen();
-          } else {
+      if (last_window_state_ == ui::SHOW_STATE_NORMAL) {
+        // Window was resized so we save it's new size.
+        last_normal_bounds_ = GetBounds();
+        last_normal_bounds_before_move_ = last_normal_bounds_;
+      } else {
+        switch (last_window_state_) {
+          case ui::SHOW_STATE_MAXIMIZED:
             last_window_state_ = ui::SHOW_STATE_NORMAL;
-            NotifyWindowRestore();
-          }
-          break;
+
+            // Don't force out last known bounds onto the window as Windows
+            // actually gets these correct
+
+            NotifyWindowUnmaximize();
+            break;
+          case ui::SHOW_STATE_MINIMIZED:
+            if (IsFullscreen()) {
+              last_window_state_ = ui::SHOW_STATE_FULLSCREEN;
+              NotifyWindowEnterFullScreen();
+            } else {
+              last_window_state_ = ui::SHOW_STATE_NORMAL;
+
+              // When the window is restored we resize it to the previous known
+              // normal size.
+              SetBounds(last_normal_bounds_, false);
+
+              NotifyWindowRestore();
+            }
+            break;
+        }
       }
       break;
   }

spec/api-browser-window-spec.js

@@ -1320,6 +1320,34 @@ describe('browser-window module', function () {
     })
   })
 
+  describe('BrowserWindow.restore()', function () {
+    it('should restore the previous window size', function () {
+      if (w != null) w.destroy()
+
+      w = new BrowserWindow({
+        minWidth: 800,
+        width: 800
+      })
+
+      const initialSize = w.getSize()
+      w.minimize()
+      w.restore()
+      assertBoundsEqual(w.getSize(), initialSize)
+    })
+  })
+
+  describe('BrowserWindow.unmaximize()', function () {
+    it('should restore the previous window position', function () {
+      if (w != null) w.destroy()
+      w = new BrowserWindow()
+
+      const initialPosition = w.getPosition()
+      w.maximize()
+      w.unmaximize()
+      assertBoundsEqual(w.getPosition(), initialPosition)
+    })
+  })
+
   describe('parent window', function () {
     let c = null