Android 键值映射

1.修改按键的键值映射
2.添加新设备kl
- 1. 设备kl命名规则1:以设备名命名
- 2. 设备kl命名规则2:以设备的vid,pid,version命名(version为可选)
3.新增自定义键值并进行键值映射
4. 使映射的按键为唤醒按键
5. 验证按键映射工具
- - 编译
- 使用
6.相关问题

1.修改按键的键值映射

修改键值映射，首先要获取到上报的按键键值,使用getevent来获取

rk3399pro:/ $ getevent
add device 1: /dev/input/event2name:     "adc-keys"
add device 2: /dev/input/event4name:     "Wireless Dongle Wireless Dongle"
add device 3: /dev/input/event5name:     "Wireless Dongle Wireless Dongle"
add device 4: /dev/input/event3name:     "rockchip,rk809-codec Headphone Jack"
add device 5: /dev/input/event1name:     "rk8xx_pwrkey"
add device 6: /dev/input/event0name:     "ff420030.pwm"/dev/input/event2: 0001 0073 00000001
/dev/input/event2: 0000 0000 00000000
/dev/input/event2: 0001 0073 00000000
/dev/input/event2: 0000 0000 00000000

其中0073即为上报的键值，转换为十进制是115，其中输入设备为

/dev/input/event2 name: “adc-keys”

查看次输入设备所对应的键值kl,使用dumpsys input

130|rk3399pro:/ $ dumpsys input
INPUT MANAGER (dumpsys input)Input Manager State:Interactive: trueSystem UI Visibility: 0x8708Pointer Speed: 0Pointer Gestures Enabled: trueShow Touches: falsePointer Capture Enabled: falseEvent Hub State:.....1: adc-keysClasses: 0x00004001Path: /dev/input/event2Enabled: trueDescriptor: 485d69228e24f5e46da1598745890b214130dbc4Location: adc-keys/input0ControllerNumber: 0UniqueId: Identifier: bus=0x0019, vendor=0x0001, product=0x0001, version=0x0100KeyLayoutFile: /system/usr/keylayout/Generic.klKeyCharacterMapFile: /system/usr/keychars/Generic.kcmConfigurationFile: HaveKeyboardLayoutOverlay: false

由上可知道对应的kl文件为 /system/usr/keylayout/Generic.kl.

修改键值映射:
挂载system为可读,打开/system/usr/keylayout/Generic.kl文件，发现115的键值已经被映射为音量加

key 115 VOLUME_UP

我们这里把他修改为静音，保存后重启测试修改有效

key 115 VOLUME_MUTE

注:支持的映射键值定义在

frameworks/native/include/android/keycodes.h
或 frameworks/native/include/input/InputEventLabels.h 中的KEYCODES[] = {}

2.添加新设备kl

以上面的为例，

/dev/input/event2 name: “adc-keys”
KeyLayoutFile: /system/usr/keylayout/Generic.kl
映射键值由 VOLUME_UP -> VOLUME_MUTE

输入设备adc-keys对应的键值为Generic.kl.如果修改了Generic.kl下的键值映射，那么对所有的输入设备都有效.如果我想只有输入设备adc-keys有效，那么我们要建立对应的kl文件即可.

1. 设备kl命名规则1:以设备名命名

设备kl的命名规则是:设备名称中除"0-9"、“a-z”、“A-Z”、"-“或”_“之外的所有字符将替换为”_"

以下输入设备为例
add device 1: /dev/input/event2
name: “adc-keys”
add device 2: /dev/input/event4
name: “Wireless Dongle Wireless Dongle”
add device 6: /dev/input/event0
name: “ff420030.pwm”

对应的设备kl名称分别为:

adc-keys.kl
Wireless_Dongle_Wireless_Dongle.kl
ff420030_pwm.kl

按照此规则,我们添加adc-keys.kl并进行键值映射

新建 system/usr/keylayout/adc-keys.kl
编辑添加 key 115 VOLUME_MUTE
保存重启

重新使用dumpsys input查看

system/usr/keylayout/adc-keys.kl
key 115 VOLUME_MUTE1: adc-keysClasses: 0x00004001Path: /dev/input/event2Enabled: trueDescriptor: 485d69228e24f5e46da1598745890b214130dbc4Location: adc-keys/input0ControllerNumber: 0UniqueId: Identifier: bus=0x0019, vendor=0x0001, product=0x0001, version=0x0100KeyLayoutFile: /system/usr/keylayout/adc-keys.klKeyCharacterMapFile: /system/usr/keychars/Generic.kcmConfigurationFile: HaveKeyboardLayoutOverlay: false

会发现adc-keys 对应的KeyLayoutFile已经改为 /system/usr/keylayout/adc-keys.kl

2. 设备kl命名规则2:以设备的vid,pid,version命名(version为可选)

设备的kl名除了以设备名转换得来以外，还可以使用设备的Vid，Pid来生成

Vendor_xxx_Product_xxxx.kl

如果当同样的vid,pid时,不同Version也要使用不同的kl映射

Vendor_xxx_Product_xxx_Version_xxx.kl

以 adc-keys为例,之前使用dumpsys input获得了如下信息

1: adc-keys
Classes: 0x00004001
Path: /dev/input/event2
Enabled: true
Descriptor: 485d69228e24f5e46da1598745890b214130dbc4
Location: adc-keys/input0
ControllerNumber: 0
UniqueId:
Identifier: bus=0x0019, vendor=0x0001, product=0x0001, version=0x0100
KeyLayoutFile: /system/usr/keylayout/Generic.kl
KeyCharacterMapFile: /system/usr/keychars/Generic.kcm
ConfigurationFile:
HaveKeyboardLayoutOverlay: false

adc-keys的vendor=0x0001, product=0x0001, version=0x0100
那么他对应的kl名是:

Vendor_0001_Product_0001.kl
Vendor_0001_Product_0001_Version_0100.kl(包含Version区分)

测试的部分和之前设备kl命名规则1相同就不重复了.

3.新增自定义键值并进行键值映射

现在的键值映射都是映射系统内已经定义的按键，那么如果我想新增一个功能键要如何实现?
定义一个键值涉及的文件是:

frameworks/base/core/java/android/view/KeyEvent.java
frameworks/native/include/android/keycodes.h
frameworks/native/include/input/InputEventLabels.h

以新增键值KeyEvent.KEYCODE_NFC为例子:


diff --git a/frameworks/base/core/java/android/view/KeyEvent.java b/frameworks/base/core/java/android/view/KeyEvent.java
index caccc04..86d9eff 100755
--- a/frameworks/base/core/java/android/view/KeyEvent.java
+++ b/frameworks/base/core/java/android/view/KeyEvent.java
@@ -835,7 +835,9 @@ public class KeyEvent extends InputEvent implements Parcelable {public static final int KEYCODE_RADAR_IN = 305;public static final int KEYCODE_RADAR_OUT = 306;-    private static final int LAST_KEYCODE = KEYCODE_RADAR_OUT;
+    public static final int KEYCODE_NFC = 307;
+
+    private static final int LAST_KEYCODE = KEYCODE_NFC;// NOTE: If you add a new keycode here you must also add it to://  isSystem()
diff --git a/frameworks/native/include/android/keycodes.h b/frameworks/native/include/android/keycodes.h
index 401d3ad..46242f6 100644
--- a/frameworks/native/include/android/keycodes.h
+++ b/frameworks/native/include/android/keycodes.h
@@ -777,7 +777,8 @@ enum {AKEYCODE_MICMUTE            = 312,AKEYCODE_RADAR_IN            = 305,
-    AKEYCODE_RADAR_OUT            = 306
+    AKEYCODE_RADAR_OUT            = 306,
+    AKEYCODE_NFC            = 307// NOTE: If you add a new keycode here you must also add it to several other files.//       Refer to frameworks/base/core/java/android/view/KeyEvent.java for the full list.
diff --git a/frameworks/native/include/input/InputEventLabels.h b/frameworks/native/include/input/InputEventLabels.h
index adab438..50794ae 100644
--- a/frameworks/native/include/input/InputEventLabels.h
+++ b/frameworks/native/include/input/InputEventLabels.h
@@ -305,6 +305,7 @@ static const InputEventLabel KEYCODES[] = {DEFINE_KEYCODE(TV_KEYMOUSE_MODE_SWITCH),DEFINE_KEYCODE(RADAR_IN),DEFINE_KEYCODE(RADAR_OUT),
+    DEFINE_KEYCODE(NFC),DEFINE_KEYCODE(HELP),DEFINE_KEYCODE(NAVIGATE_PREVIOUS),DEFINE_KEYCODE(NAVIGATE_NEXT),

最后把他映射给adc-keys的按键

打开 system/usr/keylayout/adc-keys.kl
将key 115 VOLUME_MUTE 修改为key 115 NFC
保存重启

4. 使映射的按键为唤醒按键

除了电源键外,系统内还定义了一些按键做唤醒键，当机器休眠时按下可以唤醒机器，如果想要我们映射的按键也可以唤醒屏幕的话，只需要在kl文件中做如下修改:

key 115 VOLUME_MUTE WAKE_DROPPED
#key 115 VOLUME_MUTE WAKE

WAKE: 当设备睡眠时按下此键，设备将被唤醒，按键事件将会被发送到应用程序.
WAKE_DROPPED: 当设备睡眠时按下此键，设备将被唤醒，而按键事件不会被发送到应用程序.

5. 验证按键映射工具

Android 框架有一个名为 validatekeymaps 的小工具，用于验证输入设备配置文件、按键布局文件、按键字符映射文件和虚拟按键定义文件的语法。

编译

mmm frameworks/base/tools/validatekeymaps

该命令应该会将一个名为 validatekeymaps 的主机工具编译到 out/host//bin 目录中。

使用

如果您通过运行 envsetup.sh 设置了开发环境，那么 validatekeymaps 工具应当已经位于您的路径中。您可以通过运行 validatekeymaps 进行验证。

android10.0$ validatekeymaps
Usage:
validatekeymaps [-q] [.kl] [.kcm] [.idc] [virtualkeys.] […]
Validates the specified key layouts, key character maps,
input device configurations, or virtual key definitions.
-q Quiet; do not write anything to standard out.

示例：

android10.0$ validatekeymaps frameworks/base/data/keyboards/Generic.kl
Validating file ‘frameworks/base/data/keyboards/Generic.kl’…
No errors.
Success.

编辑Generic.kl添加一个不存在的键值1_XX,再次测试

android10.0$ vim frameworks/base/data/keyboards/Generic.kl
sjf@firefly-B360-HD3:~/project/3328/android10.0$ validatekeymaps frameworks/base/data/keyboards/Generic.kl
Validating file ‘frameworks/base/data/keyboards/Generic.kl’…
E/KeyLayoutMap(20647): frameworks/base/data/keyboards/Generic.kl:24: Expected key code label, got ‘1_XX’.
Error -22 parsing key layout file.
Failed!

6.相关问题

[RK3399][Android7.1.1] keylayout键值映射:添加了自定义kl档，但仍调用默认Generic.kl的问题