Android事件处理分

核心提示：按键事件对于按键事件，调用mDevices->layoutMap->map进行映射，Android事件处理分，映射实际是由 KeyLayoutMap::map完成的，KeyLayoutMap类里读取配置文件qwerty.kl，JNI 函数在 frameworks/base/services/jni/com_

按键事件

对于按键事件，调用mDevices->layoutMap->map进行映射。映射实际是由 KeyLayoutMap::map完成的，KeyLayoutMap类里读取配置文件qwerty.kl，由配置 文件 qwerty.kl 决定键值的映射关系。你可以通过修 改./development/emulator/keymaps/qwerty.kl来改变键值的映射关系。

JNI 函数

在 frameworks/base/services/jni/com_android_server_KeyInputQueue.cpp文 件中，向 JAVA提供了函数android_server_KeyInputQueue_readEvent，用于读 取输入设备事件。

C代码：

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static jboolean android_server_KeyInputQueue_readEvent(JNIEnv* env, jobject clazz,

jobject event)

{

gLock.lock();

sp hub = gHub;

if (hub == NULL) {

hub = new EventHub;

gHub = hub;

}

gLock.unlock();

int32_t deviceId;

int32_t type;

int32_t scancode, keycode;

uint32_t flags;

int32_t value;

nsecs_t when;

bool res = hub->getEvent(&deviceId, &type, &scancode, &keycode,

&flags, &value, &when);

env->SetIntField(event, gInputOffsets.mDeviceId, (jint)deviceId);

env->SetIntField(event, gInputOffsets.mType, (jint)type);

env->SetIntField(event, gInputOffsets.mScancode, (jint)scancode);

env->SetIntField(event, gInputOffsets.mKeycode, (jint)keycode);

env->SetIntField(event, gInputOffsets.mFlags, (jint)flags);

env->SetIntField(event, gInputOffsets.mValue, value);

env->SetLongField(event, gInputOffsets.mWhen,

(jlong)(nanoseconds_to_milliseconds(when)));