| // Copyright 2014 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 COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_ |
| #define COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_ |
| |
| #include <stdint.h> |
| |
| #include <memory> |
| #include <set> |
| #include <string> |
| #include <vector> |
| |
| #include "base/macros.h" |
| #include "components/prefs/pref_store.h" |
| |
| namespace base { |
| class Value; |
| } |
| |
| // A pref store that can be written to as well as read from. |
| class COMPONENTS_PREFS_EXPORT WriteablePrefStore : public PrefStore { |
| public: |
| // PrefWriteFlags can be used to change the way a pref will be written to |
| // storage. |
| enum PrefWriteFlags : uint32_t { |
| // No flags are specified. |
| DEFAULT_PREF_WRITE_FLAGS = 0, |
| |
| // This marks the pref as "lossy". There is no strict time guarantee on when |
| // a lossy pref will be persisted to permanent storage when it is modified. |
| LOSSY_PREF_WRITE_FLAG = 1 << 1 |
| }; |
| |
| WriteablePrefStore() {} |
| |
| // Sets a |value| for |key| in the store. |value| must be non-NULL. |flags| is |
| // a bitmask of PrefWriteFlags. |
| virtual void SetValue(const std::string& key, |
| std::unique_ptr<base::Value> value, |
| uint32_t flags) = 0; |
| |
| // Removes the value for |key|. |
| virtual void RemoveValue(const std::string& key, uint32_t flags) = 0; |
| |
| // Equivalent to PrefStore::GetValue but returns a mutable value. |
| virtual bool GetMutableValue(const std::string& key, |
| base::Value** result) = 0; |
| |
| // Triggers a value changed notification. This function or |
| // ReportSubValuesChanged needs to be called if one retrieves a list or |
| // dictionary with GetMutableValue and change its value. SetValue takes care |
| // of notifications itself. Note that ReportValueChanged will trigger |
| // notifications even if nothing has changed. |flags| is a bitmask of |
| // PrefWriteFlags. |
| virtual void ReportValueChanged(const std::string& key, uint32_t flags) = 0; |
| |
| // Triggers a value changed notification for |path_components| in the |key| |
| // pref. This function or ReportValueChanged needs to be called if one |
| // retrieves a list or dictionary with GetMutableValue and change its value. |
| // SetValue takes care of notifications itself. Note that |
| // ReportSubValuesChanged will trigger notifications even if nothing has |
| // changed. |flags| is a bitmask of PrefWriteFlags. |
| virtual void ReportSubValuesChanged( |
| const std::string& key, |
| std::set<std::vector<std::string>> path_components, |
| uint32_t flags); |
| |
| // Same as SetValue, but doesn't generate notifications. This is used by |
| // PrefService::GetMutableUserPref() in order to put empty entries |
| // into the user pref store. Using SetValue is not an option since existing |
| // tests rely on the number of notifications generated. |flags| is a bitmask |
| // of PrefWriteFlags. |
| virtual void SetValueSilently(const std::string& key, |
| std::unique_ptr<base::Value> value, |
| uint32_t flags) = 0; |
| |
| protected: |
| ~WriteablePrefStore() override {} |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(WriteablePrefStore); |
| }; |
| |
| #endif // COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_ |