Clip Views textfield drag images to selected text.

ui/views/controls/textfield/textfield.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/textfield/textfield.h"
 
 #include <string>
 
 #include "base/debug/trace_event.h"
 #include "grit/ui_strings.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/clipboard/scoped_clipboard_writer.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
 #include "ui/base/dragdrop/drag_utils.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_switches_util.h"
 #include "ui/events/event.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/insets.h"
 #include "ui/native_theme/native_theme.h"
 #include "ui/views/background.h"
 #include "ui/views/controls/focusable_border.h"
+#include "ui/views/controls/label.h"
 #include "ui/views/controls/menu/menu_item_view.h"
 #include "ui/views/controls/menu/menu_runner.h"
 #include "ui/views/controls/native/native_view_host.h"
 #include "ui/views/controls/textfield/textfield_controller.h"
 #include "ui/views/drag_utils.h"
 #include "ui/views/ime/input_method.h"
 #include "ui/views/metrics.h"
 #include "ui/views/painter.h"
 #include "ui/views/views_delegate.h"
 #include "ui/views/widget/widget.h"
 
 #if defined(OS_WIN)
 #include "base/win/win_util.h"
 #endif
 
+namespace views {
+
 namespace {
 
 // Default placeholder text color.
 const SkColor kDefaultPlaceholderTextColor = SK_ColorLTGRAY;
 
-void ConvertRectToScreen(const views::View* src, gfx::Rect* r) {
+void ConvertRectToScreen(const View* src, gfx::Rect* r) {
   DCHECK(src);
 
   gfx::Point new_origin = r->origin();
-  views::View::ConvertPointToScreen(src, &new_origin);
+  View::ConvertPointToScreen(src, &new_origin);
   r->set_origin(new_origin);
 }
 
 }  // namespace
 
-namespace views {
-
 // static
 const char Textfield::kViewClassName[] = "Textfield";
 
 // static
 size_t Textfield::GetCaretBlinkMs() {
   static const size_t default_value = 500;
 #if defined(OS_WIN)
   static const size_t system_value = ::GetCaretBlinkTime();
   if (system_value != 0)
     return (system_value == INFINITE) ? 0 : system_value;
@@ skipping 753 matching lines @@
 // Textfield, TextfieldModel::Delegate overrides:
 
 void Textfield::OnCompositionTextConfirmedOrCleared() {
   if (!skip_input_method_cancel_composition_)
     GetInputMethod()->CancelComposition(this);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // Textfield, ContextMenuController overrides:
 
-void Textfield::ShowContextMenuForView(
-    View* source,
-    const gfx::Point& point,
-    ui::MenuSourceType source_type) {
+void Textfield::ShowContextMenuForView(View* source,
+                                       const gfx::Point& point,
+                                       ui::MenuSourceType source_type) {
   UpdateContextMenu();
-  if (context_menu_runner_->RunMenuAt(GetWidget(), NULL,
-          gfx::Rect(point, gfx::Size()), views::MenuItemView::TOPLEFT,
-          source_type,
-          MenuRunner::HAS_MNEMONICS | views::MenuRunner::CONTEXT_MENU) ==
-      MenuRunner::MENU_DELETED)
-    return;
+  ignore_result(context_menu_runner_->RunMenuAt(GetWidget(), NULL,
+      gfx::Rect(point, gfx::Size()), MenuItemView::TOPLEFT, source_type,
+      MenuRunner::HAS_MNEMONICS | MenuRunner::CONTEXT_MENU));
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-// Textfield, views::DragController overrides:
+// Textfield, DragController overrides:
 
-void Textfield::WriteDragDataForView(views::View* sender,
+void Textfield::WriteDragDataForView(View* sender,
                                      const gfx::Point& press_pt,
                                      OSExchangeData* data) {
-  DCHECK_NE(ui::DragDropTypes::DRAG_NONE,
-            GetDragOperationsForView(sender, press_pt));
-  data->SetString(model_->GetSelectedText());
+  const base::string16& selected_text(GetSelectedText());
+  data->SetString(selected_text);
+  Label label(selected_text, GetFontList());
+  const SkColor background = GetBackgroundColor();
+  label.SetBackgroundColor(SkColorSetA(background, SK_AlphaTRANSPARENT));
+  label.SetBoundsRect(gfx::Rect(label.GetPreferredSize()));

[sky, 2014/03/05 23:28:43]

Should this be capped in anyway? What if the text is really really long?

[msw, 2014/03/06 00:00:42]

Good point! I tried some very long strings and it drew a broken canvas on Linux
Desktop Aura and crashed ChromeOS! I changed this to cap at the display width
(and textfield height) and now the same tests draw the beginning of the string
as you might expect without crashing CrOS. Thoughts?

   scoped_ptr<gfx::Canvas> canvas(
-      views::GetCanvasForDragImage(GetWidget(), size()));
-  GetRenderText()->DrawSelectedTextForDrag(canvas.get());
-  drag_utils::SetDragImageOnDataObject(*canvas, size(),
-                                       press_pt.OffsetFromOrigin(),
-                                       data);
+      GetCanvasForDragImage(GetWidget(), label.size()));
+  label.SetEnabledColor(GetTextColor());
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+  // Desktop Linux Aura does not yet support transparency in drag images.
+  canvas->DrawColor(background);
+#endif
+  label.Paint(canvas.get());
+  static const gfx::Vector2d kOffset(-15, 0);

[sky, 2014/03/05 23:28:43]

nit: no static here.
Also, shouldn't the offset be based on the font size?

[msw, 2014/03/06 00:00:42]

Removed static. No, a (0,0) offset here puts the top left of the text drag image
at the cursor point. The 15px X-axis offset places it next to the cursor like
Unity on Goobuntu (so it's not overlapped and obscured by the cursor). The
Y-axis offset value here is ignored and clamped to 0 by
X11WholeScreenMoveLoop::SetDragImage. I think it looks okay, but perhaps we want
to change that in a followup CL?

+  drag_utils::SetDragImageOnDataObject(*canvas, label.size(), kOffset, data);
   if (controller_)
     controller_->OnWriteDragData(data);
 }
 
-int Textfield::GetDragOperationsForView(views::View* sender,
-                                        const gfx::Point& p) {
+int Textfield::GetDragOperationsForView(View* sender, const gfx::Point& p) {
   int drag_operations = ui::DragDropTypes::DRAG_COPY;
   if (!enabled() || text_input_type_ == ui::TEXT_INPUT_TYPE_PASSWORD ||
       !GetRenderText()->IsPointInSelection(p)) {
     drag_operations = ui::DragDropTypes::DRAG_NONE;
   } else if (sender == this && !read_only()) {
     drag_operations =
         ui::DragDropTypes::DRAG_MOVE | ui::DragDropTypes::DRAG_COPY;
   }
   if (controller_)
     controller_->OnGetDragOperationsForTextfield(&drag_operations);
@@ skipping 612 matching lines @@
       const size_t length = selection_clipboard_text.length();
       range = gfx::Range(range.start() + length, range.end() + length);
     }
     model_->MoveCursorTo(gfx::SelectionModel(range, affinity));
     UpdateAfterChange(true, true);
     OnAfterUserAction();
   }
 }
 
 }  // namespace views