Adds a horizontal split view.

BUG=674
TEST=none

Review URL: http://codereview.chromium.org/7930

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@3897 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 185 insertions, 1 deletions

diff --git a/chrome/views/single_split_view.cc b/chrome/views/single_split_view.cc
new file mode 100644
index 0000000..613d3e22
--- /dev/null
+++ b/chrome/views/single_split_view.cc
@@ -0,0 +1,118 @@
+// Copyright (c) 2006-2008 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 "chrome/views/single_split_view.h"
+
+#include "base/gfx/skia_utils.h"
+#include "chrome/common/gfx/chrome_canvas.h"
+
+namespace views {
+
+// Size of the divider in pixels.
+static const int kDividerSize = 6;
+
+SingleSplitView::SingleSplitView(View* leading,
+                                 View* trailing) : divider_x_(-1) {
+  AddChildView(leading);
+  AddChildView(trailing);
+}
+
+void SingleSplitView::PaintBackground(ChromeCanvas* canvas) {
+  canvas->drawColor(gfx::COLORREFToSkColor(GetSysColor(COLOR_3DFACE)),
+                    SkPorterDuff::kSrc_Mode);
+}
+
+void SingleSplitView::Layout() {
+  if (GetChildViewCount() != 2)
+    return;
+
+  View* leading = GetChildViewAt(0);
+  View* trailing = GetChildViewAt(1);
+  if (divider_x_ < 0)
+    divider_x_ = (width() - kDividerSize) / 2;
+  else
+    divider_x_ = std::min(divider_x_, width() - kDividerSize);
+  leading->SetBounds(0, 0, divider_x_, height());
+  trailing->SetBounds(divider_x_ + kDividerSize, 0,
+                      width() - divider_x_ - kDividerSize, height());
+
+  SchedulePaint();
+
+  // Invoke super's implementation so that the children are layed out.
+  View::Layout();
+}
+
+gfx::Size SingleSplitView::GetPreferredSize() {
+  int width = 0;
+  int height = 0;
+  for (int i = 0; i < 2 && i < GetChildViewCount(); ++i) {
+    View* view = GetChildViewAt(i);
+    gfx::Size pref = view->GetPreferredSize();
+    width += pref.width();
+    height = std::max(height, pref.height());
+  }
+  width += kDividerSize;
+  return gfx::Size(width, height);
+}
+
+HCURSOR SingleSplitView::GetCursorForPoint(Event::EventType event_type,
+                                           int x,
+                                           int y) {
+  if (IsPointInDivider(x)) {
+    static HCURSOR resize_cursor = LoadCursor(NULL, IDC_SIZEWE);
+    return resize_cursor;
+  }
+  return NULL;
+}
+
+bool SingleSplitView::OnMousePressed(const MouseEvent& event) {
+  if (!IsPointInDivider(event.x()))
+    return false;
+  drag_info_.initial_mouse_x = event.x();
+  drag_info_.initial_divider_x = divider_x_;
+  return true;
+}
+
+bool SingleSplitView::OnMouseDragged(const MouseEvent& event) {
+  if (GetChildViewCount() < 2)
+    return false;
+
+  int delta_x = event.x() - drag_info_.initial_mouse_x;
+  if (UILayoutIsRightToLeft())
+    delta_x *= -1;
+  // Honor the minimum size when resizing.
+  int new_width = std::max(GetChildViewAt(0)->GetMinimumSize().width(),
+                           drag_info_.initial_divider_x + delta_x);
+
+  // And don't let the view get bigger than our width.
+  new_width = std::min(width() - kDividerSize, new_width);
+
+  if (new_width != divider_x_) {
+    set_divider_x(new_width);
+    Layout();
+  }
+  return true;
+}
+
+void SingleSplitView::OnMouseReleased(const MouseEvent& event, bool canceled) {
+  if (GetChildViewCount() < 2)
+    return;
+
+  if (canceled && drag_info_.initial_divider_x != divider_x_) {
+    set_divider_x(drag_info_.initial_divider_x);
+    Layout();
+  }
+}
+
+bool SingleSplitView::IsPointInDivider(int x) {
+  if (GetChildViewCount() < 2)
+    return false;
+
+  View* leading = GetChildViewAt(0);
+  int divider_relative_x =
+      x - MirroredXCoordinateInsideView(leading->width());
+  return (divider_relative_x >= 0 && divider_relative_x < kDividerSize);
+}
+
+}  // namespace views
diff --git a/chrome/views/single_split_view.h b/chrome/views/single_split_view.h
new file mode 100644
index 0000000..b23a086
--- /dev/null
+++ b/chrome/views/single_split_view.h
@@ -0,0 +1,58 @@
+// Copyright (c) 2006-2008 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.
+
+#ifndef CHROME_VIEWS_SINGLE_SPLIT_VIEW_H_
+#define CHROME_VIEWS_SINGLE_SPLIT_VIEW_H_
+
+#include "chrome/views/view.h"
+
+namespace views {
+
+// SingleSplitView lays out two views horizontally. A splitter exists between
+// the two views that the user can drag around to resize the views.
+class SingleSplitView : public views::View {
+ public:
+  SingleSplitView(View* leading, View* trailing);
+
+  virtual void PaintBackground(ChromeCanvas* canvas);
+  virtual void Layout();
+
+  // SingleSplitView's preferred size is the sum of the preferred widths
+  // and the max of the heights.
+  virtual gfx::Size GetPreferredSize();
+
+  // Overriden to return a resize cursor when over the divider.
+  virtual HCURSOR GetCursorForPoint(Event::EventType event_type, int x, int y);
+
+  void set_divider_x(int divider_x) { divider_x_ = divider_x; }
+  int divider_x() { return divider_x_; }
+
+ protected:
+  virtual bool OnMousePressed(const MouseEvent& event);
+  virtual bool OnMouseDragged(const MouseEvent& event);
+  virtual void OnMouseReleased(const MouseEvent& event, bool canceled);
+
+ private:
+  // Returns true if |x| is over the divider.
+  bool IsPointInDivider(int x);
+
+  // Used to track drag info.
+  struct DragInfo {
+    // The initial coordinate of the mouse when the user started the drag.
+    int initial_mouse_x;
+    // The initial position of the divider when the user started the drag.
+    int initial_divider_x;
+  };
+
+  DragInfo drag_info_;
+
+  // Position of the divider.
+  int divider_x_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingleSplitView);
+};
+
+}  // namespace views
+
+#endif  // CHROME_VIEWS_SINGLE_SPLIT_VIEW_H_
diff --git a/chrome/views/view.cc b/chrome/views/view.cc
index 285aed7..7dff258 100644
--- a/chrome/views/view.cc
+++ b/chrome/views/view.cc
@@ -543,7 +543,7 @@ void View::DoDrag(const MouseEvent& e, int press_x, int press_y) {
   WriteDragData(press_x, press_y, data.get());
 
   // Message the RootView to do the drag and drop. That way if we're removed
-  // the RootView can detect it and avoid callins us back.
+  // the RootView can detect it and avoid calling us back.
   RootView* root_view = GetRootView();
   root_view->StartDragForViewFromMouseEvent(
       this, data, GetDragOperations(press_x, press_y));
diff --git a/chrome/views/views.vcproj b/chrome/views/views.vcproj
index 0a6ef96..247dbab 100644
--- a/chrome/views/views.vcproj
+++ b/chrome/views/views.vcproj
@@ -534,6 +534,14 @@
 			>
 		</File>
 		<File
+			RelativePath=".\single_split_view.cc"
+			>
+		</File>
+		<File
+			RelativePath=".\single_split_view.h"
+			>
+		</File>
+		<File
 			RelativePath=".\tabbed_pane.cc"
 			>
 		</File>