Implement taking partial screenshot.

BUG=108763
TEST=manually && aura_shell_unittests passed


Review URL: http://codereview.chromium.org/9368051

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@122281 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 123 insertions, 0 deletions

diff --git a/ash/wm/partial_screenshot_view.cc b/ash/wm/partial_screenshot_view.cc
new file mode 100644
index 0000000..bb83c5e
--- /dev/null
+++ b/ash/wm/partial_screenshot_view.cc
@@ -0,0 +1,123 @@
+// 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 "ash/wm/partial_screenshot_view.h"
+
+#include "ash/screenshot_delegate.h"
+#include "ash/shell.h"
+#include "ash/shell_window_ids.h"
+#include "ash/wm/partial_screenshot_event_filter.h"
+#include "ui/aura/cursor.h"
+#include "ui/aura/root_window.h"
+#include "ui/aura/window.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/rect.h"
+#include "ui/views/view.h"
+#include "ui/views/widget/widget.h"
+
+namespace ash {
+
+PartialScreenshotView::PartialScreenshotView(
+    ScreenshotDelegate* screenshot_delegate)
+    : is_dragging_(false),
+      screenshot_delegate_(screenshot_delegate),
+      window_(NULL) {
+}
+
+PartialScreenshotView::~PartialScreenshotView() {
+  screenshot_delegate_ = NULL;
+  // Do not delete the |window_| here because |window_| has the
+  // ownership to this object. In case that finishing browser happens
+  // while |window_| != NULL, |window_| is still removed correctly by
+  // its parent container.
+  window_ = NULL;
+}
+
+// static
+void PartialScreenshotView::StartPartialScreenshot(
+    ScreenshotDelegate* screenshot_delegate) {
+  views::Widget* widget = new views::Widget;
+  PartialScreenshotView* view = new PartialScreenshotView(
+      screenshot_delegate);
+
+  views::Widget::InitParams params(
+      views::Widget::InitParams::TYPE_WINDOW_FRAMELESS);
+  params.transparent = true;
+  params.delegate = view;
+  // The partial screenshot rectangle has to be at the real top of
+  // the screen.
+  params.parent = Shell::GetInstance()->GetContainer(
+      internal::kShellWindowId_OverlayContainer);
+
+  widget->Init(params);
+  widget->SetContentsView(view);
+  widget->SetBounds(aura::RootWindow::GetInstance()->bounds());
+  widget->GetNativeView()->SetName("PartialScreenshotView");
+  widget->StackAtTop();
+  widget->Show();
+
+  view->set_window(widget->GetNativeWindow());
+  Shell::GetInstance()->partial_screenshot_filter()->Activate(view);
+}
+
+void PartialScreenshotView::Cancel() {
+  DCHECK(window_);
+  window_->Hide();
+  Shell::GetInstance()->partial_screenshot_filter()->Deactivate();
+  MessageLoop::current()->DeleteSoon(FROM_HERE, window_);
+}
+
+gfx::NativeCursor PartialScreenshotView::GetCursor(
+    const views::MouseEvent& event) {
+  // Always use "crosshair" cursor.
+  return aura::kCursorCross;
+}
+
+void PartialScreenshotView::OnPaint(gfx::Canvas* canvas) {
+  if (is_dragging_) {
+    // Screenshot area representation: black rectangle with white
+    // rectangle inside.
+    gfx::Rect screenshot_rect = GetScreenshotRect();
+    canvas->DrawRect(screenshot_rect, SK_ColorBLACK);
+    screenshot_rect.Inset(1, 1, 1, 1);
+    canvas->DrawRect(screenshot_rect, SK_ColorWHITE);
+  }
+}
+
+bool PartialScreenshotView::OnMousePressed(const views::MouseEvent& event) {
+  start_position_ = event.location();
+  is_dragging_ = true;
+  return true;
+}
+
+bool PartialScreenshotView::OnMouseDragged(const views::MouseEvent& event) {
+  current_position_ = event.location();
+  SchedulePaint();
+  return true;
+}
+
+bool PartialScreenshotView::OnMouseWheel(const views::MouseWheelEvent& event) {
+  // Do nothing but do not propagate events futhermore.
+  return true;
+}
+
+void PartialScreenshotView::OnMouseReleased(const views::MouseEvent& event) {
+  is_dragging_ = false;
+  Cancel();
+  if (screenshot_delegate_) {
+    aura::RootWindow *root_window = aura::RootWindow::GetInstance();
+    screenshot_delegate_->HandleTakePartialScreenshot(
+        root_window, root_window->bounds().Intersect(GetScreenshotRect()));
+  }
+}
+
+gfx::Rect PartialScreenshotView::GetScreenshotRect() const {
+  int left = std::min(start_position_.x(), current_position_.x());
+  int top = std::min(start_position_.y(), current_position_.y());
+  int width = ::abs(start_position_.x() - current_position_.x());
+  int height = ::abs(start_position_.y() - current_position_.y());
+  return gfx::Rect(left, top, width, height);
+}
+
+}  // namespace ash