Makes our tables (task manager, keywords ...) not flicker when

resizing by doing nothing when we get erase background.

BUG=804753
TEST=make sure you don't get any painting artifacts in the task
manager and keyword editor.


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@1292 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 38 insertions, 5 deletions

diff --git a/chrome/views/table_view.cc b/chrome/views/table_view.cc
index d70576e..a0d9fba 100644
--- a/chrome/views/table_view.cc
+++ b/chrome/views/table_view.cc
@@ -49,8 +49,8 @@ TableView::TableView(TableModel* model,
       autosize_columns_(autosize_columns),
       resizable_columns_(resizable_columns),
       list_view_(NULL),
-      list_view_original_handler_(NULL),
       header_original_handler_(NULL),
+      original_handler_(NULL),
       table_view_wrapper_(this),
       custom_cell_font_(NULL),
       content_offset_(0) {
@@ -393,6 +393,28 @@ bool TableView::GetCellColors(int row,
   return false;
 }
 
+LRESULT CALLBACK TableView::TableWndProc(HWND window,
+                                         UINT message,
+                                         WPARAM w_param,
+                                         LPARAM l_param) {
+  TableView* table_view = reinterpret_cast<TableViewWrapper*>(
+      GetWindowLongPtr(window, GWLP_USERDATA))->table_view;
+
+  switch (message) {
+    case WM_ERASEBKGND:
+      // We make WM_ERASEBKGND do nothing (returning 1 indicates we handled
+      // the request). We do this so that the table view doesn't flicker during
+      // resizing.
+      return 1;
+
+    default:
+      break;
+  }
+  DCHECK(table_view->original_handler_);
+  return CallWindowProc(table_view->original_handler_, window, message, w_param,
+                        l_param);
+}
+
 LRESULT CALLBACK TableView::TableHeaderWndProc(HWND window, UINT message,
                                                WPARAM w_param, LPARAM l_param) {
   TableView* table_view = reinterpret_cast<TableViewWrapper*>(
@@ -512,6 +534,11 @@ HWND TableView::CreateNativeControl(HWND parent_container) {
         &TableView::TableHeaderWndProc);
   }
 
+  SetWindowLongPtr(list_view_, GWLP_USERDATA,
+      reinterpret_cast<LONG_PTR>(&table_view_wrapper_));
+  original_handler_ =
+      win_util::SetWindowProc(list_view_, &TableView::TableWndProc);
+
   // Bug 964884: detach the IME attached to this window.
   // We should attach IMEs only when we need to input CJK strings.
   ::ImmAssociateContextEx(list_view_, NULL, 0);
diff --git a/chrome/views/table_view.h b/chrome/views/table_view.h
index bcc74d3..0668120 100644
--- a/chrome/views/table_view.h
+++ b/chrome/views/table_view.h
@@ -416,6 +416,13 @@ class TableView : public NativeControl,
   // The TableColumn visible at position pos.
   const TableColumn& GetColumnAtPosition(int pos);
 
+  // Window procedure of the list view class. We subclass the list view to
+  // ignore WM_ERASEBKGND, which gives smoother painting during resizing.
+  static LRESULT CALLBACK TableWndProc(HWND window,
+                                       UINT message,
+                                       WPARAM w_param,
+                                       LPARAM l_param);
+
   // Window procedure of the header class. We subclass the header of the table
   // to disable resizing of columns.
   static LRESULT CALLBACK TableHeaderWndProc(HWND window, UINT message,
@@ -468,14 +475,13 @@ class TableView : public NativeControl,
   // a wrapper around the List-View window.
   HWND list_view_;
 
-  // The list view original proc handler. It is required when subclassing the
-  // list view.
-  WNDPROC list_view_original_handler_;
-
   // The list view's header original proc handler. It is required when
   // subclassing.
   WNDPROC header_original_handler_;
 
+  // Window procedure of the listview before we subclassed it.
+  WNDPROC original_handler_;
+
   // A wrapper around 'this' used when "subclassing" the list view and header.
   TableViewWrapper table_view_wrapper_;