ui/views/shadow_border.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/views/shadow_border.h"
   6
   7 #include "ui/gfx/canvas.h"
   8 #include "ui/gfx/geometry/insets.h"
   9 #include "ui/gfx/geometry/rect.h"
  10 #include "ui/gfx/skia_util.h"
  11 #include "ui/views/view.h"
  12
  13 namespace views {
  14
  15 namespace {
  16
  17 gfx::Insets GetInsetsFromShadowValue(const gfx::ShadowValue& shadow) {
  18   std::vector<gfx::ShadowValue> shadows;
  19   shadows.push_back(shadow);
  20   return -gfx::ShadowValue::GetMargin(shadows);
  21 }
  22
  23 }  // namespace
  24
  25 ShadowBorder::ShadowBorder(const gfx::ShadowValue& shadow)
  26     : views::Border(),
  27       shadow_value_(shadow),
  28       insets_(GetInsetsFromShadowValue(shadow)) {
  29 }
  30
  31 ShadowBorder::~ShadowBorder() {
  32 }
  33
  34 // TODO(sidharthms): Re-painting a shadow looper on every paint call may yield
  35 // poor performance. Ideally we should be caching the border to bitmaps.
  36 void ShadowBorder::Paint(const views::View& view, gfx::Canvas* canvas) {
  37   SkPaint paint;
  38   std::vector<gfx::ShadowValue> shadows;
  39   shadows.push_back(shadow_value_);
  40   skia::RefPtr<SkDrawLooper> looper = gfx::CreateShadowDrawLooper(shadows);
  41   paint.setLooper(looper.get());
  42   paint.setColor(SK_ColorTRANSPARENT);
  43   paint.setStrokeJoin(SkPaint::kRound_Join);
  44   gfx::Rect bounds(view.size());
  45   bounds.Inset(-gfx::ShadowValue::GetMargin(shadows));
  46   canvas->DrawRect(bounds, paint);
  47 }
  48
  49 gfx::Insets ShadowBorder::GetInsets() const {
  50   return insets_;
  51 }
  52
  53 gfx::Size ShadowBorder::GetMinimumSize() const {
  54   return gfx::Size(shadow_value_.blur(), shadow_value_.blur());
  55 }
  56
  57 }  // namespace views