Grab mouse capture in the WM_POINTERDOWN message handler in the omnibox.

chrome/browser/ui/views/omnibox/omnibox_view_win.cc

Index: chrome/browser/ui/views/omnibox/omnibox_view_win.cc
===================================================================
--- chrome/browser/ui/views/omnibox/omnibox_view_win.cc	(revision 160963)
+++ chrome/browser/ui/views/omnibox/omnibox_view_win.cc	(working copy)
@@ -1371,6 +1371,11 @@
     // Enable TSF support of RichEdit.
     SetEditStyle(SES_USECTF, SES_USECTF);
   }
+
+  if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
+    bool touch_mode = RegisterTouchWindow(m_hWnd, TWF_WANTPALM) == TRUE;

[Peter Kasting, 2012/10/11 23:13:34]

Nit: Just auto-convert to bool, don't explicitly check "== TRUE"

[ananta, 2012/10/11 23:48:41]

Replaced with !! as auto conversion gets a compiler warning.

[Peter Kasting, 2012/10/12 00:19:59]

Suck.  In that case, maybe it'd be even better to declare touch_mode as BOOL --
the DCHECK() will still work.

+    DCHECK(touch_mode);
+  }
   SetMsgHandled(FALSE);
   return 0;
 }
@@ -1394,6 +1399,11 @@
   return 0;
 }
 
+void OmniboxViewWin::OnDestroy() {
+  if (base::win::GetVersion() >= base::win::VERSION_WIN8)
+    UnregisterTouchWindow(m_hWnd);
+}
+
 LRESULT OmniboxViewWin::OnImeComposition(UINT message,
                                          WPARAM wparam,
                                          LPARAM lparam) {
@@ -1446,6 +1456,26 @@
   return DefWindowProc(message, wparam, lparam);
 }
 
+LRESULT OmniboxViewWin::OnTouchEvent(UINT message,
+                                     WPARAM wparam,
+                                     LPARAM lparam) {
+  if (wparam == 1) {

[Peter Kasting, 2012/10/11 23:13:34]

Shouldn't this also check "&& !model()->has_focus()"?

[ananta, 2012/10/11 23:48:41]

We can't do that as the WM_POINTERDOWN handler which sets focus is invoked
before the touch handler.

[ananta, 2012/10/11 23:53:11]

I moved the SetFocus call from OnPointerDown to the TOUCHEVENTF_DOWN if below.

+    TOUCHINPUT point = {0};
+    if (GetTouchInputInfo(reinterpret_cast<HTOUCHINPUT>(lparam), 1,
+                          &point, sizeof(TOUCHINPUT))) {
+      // There is a bug in Windows 8 where in the generated mouse messages
+      // after touch go to the window which previously had focus. We set
+      // capture here to ensure that the generated mouse messages come to us.

[Peter Kasting, 2012/10/11 23:13:34]

Nit: If you move this comment to be at the beginning of the function, you can
add something like:

"...previously had focus.  This means that if a user taps the omnibox to give it
focus, we don't get the simulated WM_LBUTTONDOWN, and thus don't properly select
all the text.  To ensure we get this message, we capture the mouse when the user
is doing a single-point tap on an unfocused model."

[ananta, 2012/10/11 23:48:41]

Done.

+      if (point.dwFlags & TOUCHEVENTF_DOWN)
+        SetCapture();
+      else if (point.dwFlags & TOUCHEVENTF_UP)
+        ReleaseCapture();
+    }
+  }
+  SetMsgHandled(false);
+  return 0;
+}
+
 LRESULT OmniboxViewWin::OnPointerDown(UINT message,
                                       WPARAM wparam,
                                       LPARAM lparam) {
@@ -1456,16 +1486,13 @@
     TrackMousePosition(kLeft, CPoint(GET_X_LPARAM(lparam),
                                      GET_Y_LPARAM(lparam)));
   }
-
   SetMsgHandled(false);
-
   return 0;
 }
 
 LRESULT OmniboxViewWin::OnPointerUp(UINT message, WPARAM wparam,
                                     LPARAM lparam) {
   SetMsgHandled(false);

[Peter Kasting, 2012/10/11 23:13:34]

Nit: If this is all this function does, can't we just remove the WM_POINTERUP
macro from the header or something?

[ananta, 2012/10/11 23:48:41]

Done.

-
   return 0;
 }