Android按键灯步骤分析

发布时间：2021-12-13 11:17:53 所属栏目：教程来源：互联网

导读：调用代码为： alpsframeworksbaseservicesjavacomAndroidserverLightsService.java 使用方法： private LightsService.Light mButtonLight; mButtonLight = mLightsService.getLight(LightsService.LIGHT_ID_BUTTONS); mButtonLight.setBrightness(s

调用代码为：

alpsframeworksbaseservicesjavacomAndroidserverLightsService.java

使用方法：
private LightsService.Light mButtonLight;
mButtonLight = mLightsService.getLight(LightsService.LIGHT_ID_BUTTONS);
mButtonLight.setBrightness(screenBrightness);
mButtonLight.turnOff();

本地代码在：
alpsframeworksbaseservicesjnicom_android_server_LightsService.cpp

接口关联使用：
static JNINativeMethod method_table[] = {
    { "init_native", "()I", (void*)init_native },
    { "finalize_native", "(I)V", (void*)finalize_native },
    { "setLight_native", "(IIIIIII)V", (void*)setLight_native },
};

int register_android_server_LightsService(JNIEnv *env)
{
    return jniRegisterNativeMethods(env, "com/android/server/LightsService",
            method_table, NELEM(method_table));
}

register_android_server_LightsService函数在alpsframeworksbaseservicesjnionload.cpp里面注册

本地c代码在：
alpsmediatekhardwareliblightslights.c里面open_lights里面

static int
set_light_buttons(struct light_device_t* dev,
        struct light_state_t const* state)
{
    int err = 0;
    int on = is_lit(state);
    pthread_mutex_lock(&g_lock);
    g_buttons = on;
    err = write_int(BUTTON_FILE, on?255:0);
    pthread_mutex_unlock(&g_lock);
    return err;
}

com_android_server_LightsService.cp里面使用 devices->lights[light]->set_light(devices->lights[light], &state);来调用真正的代码
如果有root机子，可以如下测试：
echo 0 > /sys/class/leds/button-backlight/brightness 关按键灯
  echo 1 > /sys/class/leds/button-backlight/brightness 开按键灯

  echo 0 > /sys/class/leds/button-backlight/brightness 执行的意思为：输出0，作为/sys/class/leds/button-backlight/brightness的输入传入。
  如此便会打开brightness设备，并执行write将0带入执行。

（编辑：PHP编程网 - 黄冈站长网）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!

采用gpt分区无法安装系	跟你说进程管理器快捷
电脑装机必备清单	小编教你联想笔记本进