replicant-frameworks_native/include/input/KeyCharacterMap.h
Dmitry Torokhov 115f93eeeb Allow defining replacement key events in keymap
Currently keyboard maps allow to assign character sequences to key
events and allow specifying a so-called "fallback" key events that are
re-injected into input stream if target application indicates that it
was not able to handle the original key event. Unfortunately there is no
way to perform substitution before handing the event to applicationis.

This change adds a new keymap keyword "replace" that allows users query
"replacement" actions for key (if any), with the intent that such
replacement happens early in the event handling process.

Bug: 24504154

Change-Id: I3e6a2476c856524171df00ad22ff56f2018c1278
2015-09-29 13:26:30 -07:00

266 lines
8.8 KiB
C++

/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _LIBINPUT_KEY_CHARACTER_MAP_H
#define _LIBINPUT_KEY_CHARACTER_MAP_H
#include <stdint.h>
#if HAVE_ANDROID_OS
#include <binder/IBinder.h>
#endif
#include <input/Input.h>
#include <utils/Errors.h>
#include <utils/KeyedVector.h>
#include <utils/Tokenizer.h>
#include <utils/String8.h>
#include <utils/Unicode.h>
#include <utils/RefBase.h>
namespace android {
/**
* Describes a mapping from Android key codes to characters.
* Also specifies other functions of the keyboard such as the keyboard type
* and key modifier semantics.
*
* This object is immutable after it has been loaded.
*/
class KeyCharacterMap : public RefBase {
public:
enum KeyboardType {
KEYBOARD_TYPE_UNKNOWN = 0,
KEYBOARD_TYPE_NUMERIC = 1,
KEYBOARD_TYPE_PREDICTIVE = 2,
KEYBOARD_TYPE_ALPHA = 3,
KEYBOARD_TYPE_FULL = 4,
KEYBOARD_TYPE_SPECIAL_FUNCTION = 5,
KEYBOARD_TYPE_OVERLAY = 6,
};
enum Format {
// Base keyboard layout, may contain device-specific options, such as "type" declaration.
FORMAT_BASE = 0,
// Overlay keyboard layout, more restrictive, may be published by applications,
// cannot override device-specific options.
FORMAT_OVERLAY = 1,
// Either base or overlay layout ok.
FORMAT_ANY = 2,
};
// Substitute key code and meta state for fallback action.
struct FallbackAction {
int32_t keyCode;
int32_t metaState;
};
/* Loads a key character map from a file. */
static status_t load(const String8& filename, Format format, sp<KeyCharacterMap>* outMap);
/* Loads a key character map from its string contents. */
static status_t loadContents(const String8& filename,
const char* contents, Format format, sp<KeyCharacterMap>* outMap);
/* Combines a base key character map and an overlay. */
static sp<KeyCharacterMap> combine(const sp<KeyCharacterMap>& base,
const sp<KeyCharacterMap>& overlay);
/* Returns an empty key character map. */
static sp<KeyCharacterMap> empty();
/* Gets the keyboard type. */
int32_t getKeyboardType() const;
/* Gets the primary character for this key as in the label physically printed on it.
* Returns 0 if none (eg. for non-printing keys). */
char16_t getDisplayLabel(int32_t keyCode) const;
/* Gets the Unicode character for the number or symbol generated by the key
* when the keyboard is used as a dialing pad.
* Returns 0 if no number or symbol is generated.
*/
char16_t getNumber(int32_t keyCode) const;
/* Gets the Unicode character generated by the key and meta key modifiers.
* Returns 0 if no character is generated.
*/
char16_t getCharacter(int32_t keyCode, int32_t metaState) const;
/* Gets the fallback action to use by default if the application does not
* handle the specified key.
* Returns true if an action was available, false if none.
*/
bool getFallbackAction(int32_t keyCode, int32_t metaState,
FallbackAction* outFallbackAction) const;
/* Gets the first matching Unicode character that can be generated by the key,
* preferring the one with the specified meta key modifiers.
* Returns 0 if no matching character is generated.
*/
char16_t getMatch(int32_t keyCode, const char16_t* chars,
size_t numChars, int32_t metaState) const;
/* Gets a sequence of key events that could plausibly generate the specified
* character sequence. Returns false if some of the characters cannot be generated.
*/
bool getEvents(int32_t deviceId, const char16_t* chars, size_t numChars,
Vector<KeyEvent>& outEvents) const;
/* Maps a scan code and usage code to a key code, in case this key map overrides
* the mapping in some way. */
status_t mapKey(int32_t scanCode, int32_t usageCode, int32_t* outKeyCode) const;
/* Tries to find a replacement key code for a given key code and meta state
* in character map. */
void tryRemapKey(int32_t scanCode, int32_t metaState,
int32_t* outKeyCode, int32_t* outMetaState) const;
#if HAVE_ANDROID_OS
/* Reads a key map from a parcel. */
static sp<KeyCharacterMap> readFromParcel(Parcel* parcel);
/* Writes a key map to a parcel. */
void writeToParcel(Parcel* parcel) const;
#endif
protected:
virtual ~KeyCharacterMap();
private:
struct Behavior {
Behavior();
Behavior(const Behavior& other);
/* The next behavior in the list, or NULL if none. */
Behavior* next;
/* The meta key modifiers for this behavior. */
int32_t metaState;
/* The character to insert. */
char16_t character;
/* The fallback keycode if the key is not handled. */
int32_t fallbackKeyCode;
/* The replacement keycode if the key has to be replaced outright. */
int32_t replacementKeyCode;
};
struct Key {
Key();
Key(const Key& other);
~Key();
/* The single character label printed on the key, or 0 if none. */
char16_t label;
/* The number or symbol character generated by the key, or 0 if none. */
char16_t number;
/* The list of key behaviors sorted from most specific to least specific
* meta key binding. */
Behavior* firstBehavior;
};
class Parser {
enum State {
STATE_TOP = 0,
STATE_KEY = 1,
};
enum {
PROPERTY_LABEL = 1,
PROPERTY_NUMBER = 2,
PROPERTY_META = 3,
};
struct Property {
inline Property(int32_t property = 0, int32_t metaState = 0) :
property(property), metaState(metaState) { }
int32_t property;
int32_t metaState;
};
KeyCharacterMap* mMap;
Tokenizer* mTokenizer;
Format mFormat;
State mState;
int32_t mKeyCode;
public:
Parser(KeyCharacterMap* map, Tokenizer* tokenizer, Format format);
~Parser();
status_t parse();
private:
status_t parseType();
status_t parseMap();
status_t parseMapKey();
status_t parseKey();
status_t parseKeyProperty();
status_t finishKey(Key* key);
status_t parseModifier(const String8& token, int32_t* outMetaState);
status_t parseCharacterLiteral(char16_t* outCharacter);
};
static sp<KeyCharacterMap> sEmpty;
KeyedVector<int32_t, Key*> mKeys;
int mType;
KeyedVector<int32_t, int32_t> mKeysByScanCode;
KeyedVector<int32_t, int32_t> mKeysByUsageCode;
KeyCharacterMap();
KeyCharacterMap(const KeyCharacterMap& other);
bool getKey(int32_t keyCode, const Key** outKey) const;
bool getKeyBehavior(int32_t keyCode, int32_t metaState,
const Key** outKey, const Behavior** outBehavior) const;
static bool matchesMetaState(int32_t eventMetaState, int32_t behaviorMetaState);
bool findKey(char16_t ch, int32_t* outKeyCode, int32_t* outMetaState) const;
static status_t load(Tokenizer* tokenizer, Format format, sp<KeyCharacterMap>* outMap);
static void addKey(Vector<KeyEvent>& outEvents,
int32_t deviceId, int32_t keyCode, int32_t metaState, bool down, nsecs_t time);
static void addMetaKeys(Vector<KeyEvent>& outEvents,
int32_t deviceId, int32_t metaState, bool down, nsecs_t time,
int32_t* currentMetaState);
static bool addSingleEphemeralMetaKey(Vector<KeyEvent>& outEvents,
int32_t deviceId, int32_t metaState, bool down, nsecs_t time,
int32_t keyCode, int32_t keyMetaState,
int32_t* currentMetaState);
static void addDoubleEphemeralMetaKey(Vector<KeyEvent>& outEvents,
int32_t deviceId, int32_t metaState, bool down, nsecs_t time,
int32_t leftKeyCode, int32_t leftKeyMetaState,
int32_t rightKeyCode, int32_t rightKeyMetaState,
int32_t eitherKeyMetaState,
int32_t* currentMetaState);
static void addLockedMetaKey(Vector<KeyEvent>& outEvents,
int32_t deviceId, int32_t metaState, nsecs_t time,
int32_t keyCode, int32_t keyMetaState,
int32_t* currentMetaState);
};
} // namespace android
#endif // _LIBINPUT_KEY_CHARACTER_MAP_H