| // 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 UI_OZONE_PUBLIC_KEYBOARD_LAYOUT_ENGINE_H_ |
| #define UI_OZONE_PUBLIC_KEYBOARD_LAYOUT_ENGINE_H_ |
| |
| #include <string> |
| |
| #include "base/strings/string16.h" |
| #include "ui/events/keycodes/dom/dom_key.h" |
| #include "ui/events/keycodes/keyboard_codes.h" |
| #include "ui/events/ozone/layout/events_ozone_layout_export.h" |
| |
| namespace ui { |
| |
| enum class DomCode; |
| |
| // A KeyboardLayoutEngine provides a platform-independent interface to |
| // key mapping. Key mapping provides a meaning (DomKey and character, |
| // and optionally Windows key code) for a physical key press (DomCode |
| // and modifier flags). |
| // |
| // This interface does not expose individual layouts because it must support |
| // platforms that only provide for one active system layout, and/or platforms |
| // where layouts have no accessible representation. |
| class EVENTS_OZONE_LAYOUT_EXPORT KeyboardLayoutEngine { |
| public: |
| KeyboardLayoutEngine() {} |
| virtual ~KeyboardLayoutEngine() {} |
| |
| // Returns true if it is possible to change the current layout. |
| virtual bool CanSetCurrentLayout() const = 0; |
| |
| // Sets the current layout; returns true on success. |
| // Drop-in replacement for ImeKeyboard::SetCurrentKeyboardLayoutByName(); |
| // the argument string is defined by that interface (crbug.com/362698). |
| virtual bool SetCurrentLayoutByName(const std::string& layout_name) = 0; |
| |
| // Sets the current layout given a memory location and the buffer size in |
| // bytes, that represent keyboard mapping description; returns true on |
| // success. |
| virtual bool SetCurrentLayoutFromBuffer(const char* keymap_string, |
| size_t size) = 0; |
| |
| // Returns true if the current layout makes use of the ISO Level 5 Shift key. |
| // Drop-in replacement for ImeKeyboard::IsISOLevel5ShiftAvailable(). |
| virtual bool UsesISOLevel5Shift() const = 0; |
| |
| // Returns true if the current layout makes use of the AltGr |
| // (ISO Level 3 Shift) key. |
| // Drop-in replacement for ImeKeyboard::IsAltGrAvailable(). |
| virtual bool UsesAltGr() const = 0; |
| |
| // Provides the meaning of a physical key. |
| // |
| // The caller must supply valid addresses for all the output parameters; |
| // the function must not use their initial values. |
| // |
| // Returns true if it can determine the DOM meaning (i.e. ui::DomKey and |
| // character) and the corresponding (non-located) KeyboardCode from the given |
| // physical state (ui::DomCode and ui::EventFlags), OR if it can determine |
| // that there is no meaning in the current layout (e.g. the key is unbound). |
| // In the latter case, the function sets *dom_key to UNIDENTIFIED and |
| // *key_code to VKEY_UNKNOWN. |
| // |
| // Returns false if it cannot determine the meaning (and cannot determine |
| // that there is none); in this case it does not set any of the output |
| // parameters. |
| virtual bool Lookup(DomCode dom_code, |
| int event_flags, |
| DomKey* dom_key, |
| KeyboardCode* key_code) const = 0; |
| }; |
| |
| } // namespace ui |
| |
| #endif // UI_OZONE_PUBLIC_KEYBOARD_LAYOUT_ENGINE_H_ |