1 // Copyright 2012 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef COMPONENTS_PREFS_DEFAULT_PREF_STORE_H_
6 #define COMPONENTS_PREFS_DEFAULT_PREF_STORE_H_
11 #include "base/observer_list.h"
12 #include "base/strings/string_piece.h"
13 #include "base/values.h"
14 #include "components/prefs/pref_store.h"
15 #include "components/prefs/pref_value_map.h"
16 #include "components/prefs/prefs_export.h"
18 // Used within a PrefRegistry to keep track of default preference values.
19 class COMPONENTS_PREFS_EXPORT DefaultPrefStore : public PrefStore {
21 typedef PrefValueMap::const_iterator const_iterator;
25 DefaultPrefStore(const DefaultPrefStore&) = delete;
26 DefaultPrefStore& operator=(const DefaultPrefStore&) = delete;
28 // PrefStore implementation:
29 bool GetValue(base::StringPiece key,
30 const base::Value** result) const override;
31 base::Value::Dict GetValues() const override;
32 void AddObserver(PrefStore::Observer* observer) override;
33 void RemoveObserver(PrefStore::Observer* observer) override;
34 bool HasObservers() const override;
36 // Sets a |value| for |key|. Should only be called if a value has not been
37 // set yet; otherwise call ReplaceDefaultValue().
38 void SetDefaultValue(const std::string& key, base::Value value);
40 // Replaces the the value for |key| with a new value. Should only be called
41 // if a value has alreday been set; otherwise call SetDefaultValue().
42 void ReplaceDefaultValue(const std::string& key, base::Value value);
44 const_iterator begin() const;
45 const_iterator end() const;
48 ~DefaultPrefStore() override;
52 base::ObserverList<PrefStore::Observer, true>::Unchecked observers_;
55 #endif // COMPONENTS_PREFS_DEFAULT_PREF_STORE_H_