Rework the command updater to not be dependent on views::Button (needed for porting).

TEST=make sure back/forward buttons still enable/disable correctly depending on the length of the back/forward navigation list.
Review URL: http://codereview.chromium.org/18343

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@8332 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 61 insertions, 0 deletions

diff --git a/chrome/browser/command_updater.cc b/chrome/browser/command_updater.cc
new file mode 100644
index 0000000..8839965
--- /dev/null
+++ b/chrome/browser/command_updater.cc
@@ -0,0 +1,61 @@
+// 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 <algorithm>
+
+#include "chrome/browser/command_updater.h"
+
+#include "base/logging.h"
+#include "chrome/common/stl_util-inl.h"
+
+CommandUpdater::CommandUpdater(CommandUpdaterDelegate* handler)
+    : delegate_(handler) {
+}
+
+CommandUpdater::~CommandUpdater() {
+  STLDeleteContainerPairSecondPointers(commands_.begin(), commands_.end());
+}
+
+bool CommandUpdater::IsCommandEnabled(int id) const {
+  const CommandMap::const_iterator command(commands_.find(id));
+  if (command == commands_.end())
+    return false;
+  return command->second->enabled;
+}
+
+bool CommandUpdater::SupportsCommand(int id) const {
+  return commands_.find(id) != commands_.end();
+}
+
+void CommandUpdater::ExecuteCommand(int id) {
+  if (IsCommandEnabled(id))
+    delegate_->ExecuteCommand(id);
+}
+
+void CommandUpdater::UpdateCommandEnabled(int id, bool enabled) {
+  Command* command = GetCommand(id, true);
+  if (command->enabled == enabled)
+    return;  // Nothing to do.
+  command->enabled = enabled;
+  FOR_EACH_OBSERVER(CommandObserver, command->observers,
+                    EnabledStateChangedForCommand(id, enabled));
+}
+
+CommandUpdater::Command* CommandUpdater::GetCommand(int id, bool create) {
+  bool supported = SupportsCommand(id);
+  if (supported)
+    return commands_[id];
+  DCHECK(create);
+  Command* command = new Command;
+  commands_[id] = command;
+  return command;
+}
+
+void CommandUpdater::AddCommandObserver(int id, CommandObserver* observer) {
+  GetCommand(id, true)->observers.AddObserver(observer);
+}
+
+void CommandUpdater::RemoveCommandObserver(int id, CommandObserver* observer) {
+  GetCommand(id, false)->observers.RemoveObserver(observer);
+}