Merge pull request #12904 from electron/fix-12875

Allow frameless transparent windows to be sized smaller than 64x64 on Windows

atom/browser/native_window.cc

@@ -4,6 +4,7 @@
 
 #include "atom/browser/native_window.h"
 
+#include <algorithm>
 #include <string>
 #include <utility>
 #include <vector>
@@ -15,10 +16,35 @@
 #include "native_mate/dictionary.h"
 #include "ui/views/widget/widget.h"
 
+#if defined(OS_WIN)
+#include "ui/base/win/shell.h"
+#include "ui/display/win/screen_win.h"
+#endif
+
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(atom::NativeWindowRelay);
 
 namespace atom {
 
+namespace {
+
+#if defined(OS_WIN)
+gfx::Size GetExpandedWindowSize(const NativeWindow* window, gfx::Size size) {
+  if (!window->transparent() || !ui::win::IsAeroGlassEnabled())
+    return size;
+
+  gfx::Size min_size = display::win::ScreenWin::ScreenToDIPSize(
+      window->GetAcceleratedWidget(), gfx::Size(64, 64));
+
+  // Some AMD drivers can't display windows that are less than 64x64 pixels,
+  // so expand them to be at least that size. http://crbug.com/286609
+  gfx::Size expanded(std::max(size.width(), min_size.width()),
+                     std::max(size.height(), min_size.height()));
+  return expanded;
+}
+#endif
+
+}  // namespace
+
 NativeWindow::NativeWindow(const mate::Dictionary& options,
                            NativeWindow* parent)
     : widget_(new views::Widget),
@@ -254,6 +280,19 @@ gfx::Size NativeWindow::GetMaximumSize() const {
   return GetSizeConstraints().GetMaximumSize();
 }
 
+gfx::Size NativeWindow::GetContentMinimumSize() const {
+  return GetContentSizeConstraints().GetMinimumSize();
+}
+
+gfx::Size NativeWindow::GetContentMaximumSize() const {
+  gfx::Size maximum_size = GetContentSizeConstraints().GetMaximumSize();
+#if defined(OS_WIN)
+  return GetExpandedWindowSize(this, maximum_size);
+#else
+  return maximum_size;
+#endif
+}
+
 void NativeWindow::SetSheetOffset(const double offsetX, const double offsetY) {
   sheet_offset_x_ = offsetX;
   sheet_offset_y_ = offsetY;

atom/browser/native_window.h

@@ -102,6 +102,8 @@ class NativeWindow : public base::SupportsUserData,
   virtual gfx::Size GetMinimumSize() const;
   virtual void SetMaximumSize(const gfx::Size& size);
   virtual gfx::Size GetMaximumSize() const;
+  virtual gfx::Size GetContentMinimumSize() const;
+  virtual gfx::Size GetContentMaximumSize() const;
   virtual void SetSheetOffset(const double offsetX, const double offsetY);
   virtual double GetSheetOffsetX();
   virtual double GetSheetOffsetY();

atom/browser/ui/views/frameless_view.cc

@@ -100,11 +100,11 @@ gfx::Size FramelessView::CalculatePreferredSize() const {
 }
 
 gfx::Size FramelessView::GetMinimumSize() const {
-  return window_->GetContentSizeConstraints().GetMinimumSize();
+  return window_->GetContentMinimumSize();
 }
 
 gfx::Size FramelessView::GetMaximumSize() const {
-  return window_->GetContentSizeConstraints().GetMaximumSize();
+  return window_->GetContentMaximumSize();
 }
 
 const char* FramelessView::GetClassName() const {

spec/api-browser-window-spec.js

@@ -2235,6 +2235,24 @@ describe('BrowserWindow module', () => {
           assert.equal(w.isResizable(), false)
         }
       })
+
+      if (process.platform === 'win32') {
+        it('works for a window smaller than 64x64', () => {
+          w.destroy()
+          w = new BrowserWindow({
+            show: false,
+            frame: false,
+            resizable: false,
+            transparent: true
+          })
+          w.setContentSize(60, 60)
+          assertBoundsEqual(w.getContentSize(), [60, 60])
+          w.setContentSize(30, 30)
+          assertBoundsEqual(w.getContentSize(), [30, 30])
+          w.setContentSize(10, 10)
+          assertBoundsEqual(w.getContentSize(), [10, 10])
+        })
+      }
     })
 
     describe('loading main frame state', () => {