rk3368 Android9.0 HIDL调试记录


rk3368 Android9.0 HIDL调试记录

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Platform: RK3368
OS: Android 9.0
Kernel: 4.4.194

文章目录

  • rk3368 Android9.0 HIDL调试记录
    • 1. 使用hidl-gen工具生成接口
      • 1.1 hidl-gen使用方法
      • 1.2 创建HIDL文件
      • 1.3 使用hidl-gen工具生成HIDL相关文件
    • 2. 修改代码
      • 2.1 创建service代码
      • 2.2 修改Android.bp添加编译service
      • 2.3 添加启动service的init.rc文件
      • 2.4 修改生成的代码
      • 2.5 添加本地C++测试代码
    • 3. 编译测试
      • 3.1 mmm单独模块编译:
      • 3.2 Native测试
      • 3.3 Android APP java测试

在Android 8.0以后，低层已重新编写以采用更加模块化的新架构。必须支持使用 HIDL 语言编写的 HAL，下面列出了一些例外情况。这些 HAL 可以是绑定式 HAL 也可以是直通式 HAL.

绑定式 HAL 以 HAL 接口定义语言 (HIDL) 或 Android 接口定义语言 (AIDL) 表示的 HAL。这些 HAL 取代了早期 Android 版本中使用的传统 HAL 和旧版 HAL。在绑定式 HAL 中，Android 框架和 HAL 之间通过 Binder 进程间通信 (IPC) 调用进行通信。所有在推出时即搭载了 Android 8.0 或更高版本的设备都必须只支持绑定式 HAL。

直通式 HAL 以 HIDL 封装的传统 HAL 或旧版 HAL。这些 HAL 封装了现有的 HAL，可在绑定模式和 Same-Process（直通）模式下使用。升级到 Android 8.0 的设备可以使用直通式 HAL。

此调试记录为绑定式 HAL;

1. 使用hidl-gen工具生成接口

1.1 hidl-gen使用方法

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$ hidl-gen -h
usage: hidl-gen [-p <root path>] -o <output path> -L <language> [-O <owner>] (-r <interface root>)+ [-v] [-d <depfile>] FQNAME...

Process FQNAME, PACKAGE(.SUBPACKAGE)*@[0-9]+.[0-9]+(::TYPE)?, to create output.

         -h: Prints this menu.
         -L <language>: The following options are available:
            check           : Parses the interface to see if valid but doesn't write any files.
            c++             : (internal) (deprecated) Generates C++ interface files for talking to HIDL interfaces.
            c++-headers     : (internal) Generates C++ headers for interface files for talking to HIDL interfaces.
            c++-sources     : (internal) Generates C++ sources for interface files for talking to HIDL interfaces.
            export-header   : Generates a header file from @export enumerations to help maintain legacy code.
            c++-impl        : Generates boilerplate implementation of a hidl interface in C++ (for convenience).
            c++-impl-headers: c++-impl but headers only
            c++-impl-sources: c++-impl but sources only
            c++-adapter     : Takes a x.(y+n) interface and mocks an x.y interface.
            c++-adapter-headers: c++-adapter but helper headers only
            c++-adapter-sources: c++-adapter but helper sources only
            c++-adapter-main: c++-adapter but the adapter binary source only
            java            : (internal) Generates Java library for talking to HIDL interfaces in Java.
            java-constants  : (internal) Like export-header but for Java (always created by -Lmakefile if @export exists).
            vts             : (internal) Generates vts proto files for use in vtsd.
            makefile        : (removed) Used to generate makefiles for -Ljava and -Ljava-constants.
            androidbp       : (internal) Generates Soong bp files for -Lc++-headers, -Lc++-sources, -Ljava, -Ljava-constants, and -Lc++-adapter.
            androidbp-impl  : Generates boilerplate bp files for implementation created with -Lc++-impl.
            hash            : Prints hashes of interface in `current.txt` format to standard out.
         -O <owner>: The owner of the module for -Landroidbp(-impl)?.
         -o <output path>: Location to output files.
         -p <root path>: Android build root, defaults to $ANDROID_BUILD_TOP or pwd.
         -r <package:path root>: E.g., android.hardware:hardware/interfaces.
         -v: verbose output.
         -d <depfile>: location of depfile to write to.

1.2 创建HIDL文件

  1. 新建目录vendor/sample/hardware/interfaces/helloworld/1.0
  2. 创建文件: IHelloWorld.hal IHelloWorldCallback.hal types.hal

不要直接在Android源码目录hardware/interfaces下面添加和修改接口,在API锁定分支中不允许更改VNDK库列表.

其中vendor/sample/hardware/interfaces就是hidl的root path了.

helloworld/1.0/IHelloWorld.hal

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package [email protected];

import IHelloWorldCallback;

interface IHelloWorld {
    initial();
    getInt() generates (int32_t i);
    setInt(int32_t val) generates (Result error);
    oneway setCallback(IHelloWorldCallback callback);
 };

helloworld/1.0/IHelloWorldCallback.hal

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package [email protected];

interface IHelloWorldCallback {
    oneway onEvent(Event event);
 };

helloworld/1.0/types.hal

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package [email protected];
enum Result : int32_t {
    OK,
    UNKNOWN,
    INVALID_ARGUMENTS,
};

struct Event {
    uint32_t type;
    uint32_t code;
    uint32_t value;
};
  1. 指定HIDL包根目录
    添加文件vendor/sample/hardware/interfaces/Android.bp
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hidl_package_root {
    name: "sample.hardware",
    path: "vendor/sample/hardware/interfaces",
}

如果不指定HIDL包根目录,编译会报错:Cannot find package root specification

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interfaces: Cannot find package root specification for package root 'sample.hardware' needed for module '[email protected]'. Either this is a mispelling of the package root, or a new hidl_package_root module needs to be added. For example, you can fix this error by adding the following to <some path>/Android.bp:

hidl_package_root {
    name: "sample.hardware",
    path: "<some path>",
}
  1. 生成HIDL哈希
    每个软件包根目录（即映射到 hardware/interfaces 的 android.hardware 或映射到 vendor/foo/hardware/interfaces 的 vendor.foo）都必须包含一个列出所有已发布 HIDL 接口文件的 current.txt 文件。
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$ hidl-gen -Lhash -rsample.hardware:vendor/sample/hardware/interfaces -randroid.hidl:system/libhidl/transport [email protected]> vendor/sample/hardware/interfaces/current.txt

1.3 使用hidl-gen工具生成HIDL相关文件

  1. 使用hidl-gen生成C++文件
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$ hidl-gen -o vendor/sample/hardware/interfaces/helloworld/1.0/default -Lc++-impl -rsample.hardware:vendor/sample/hardware/interfaces -randroid.hidl:system/libhidl/transport [email protected]

把生成的下面两个不用的文件删除:
helloworld/1.0/default/HelloWorldCallback.cpp
helloworld/1.0/default/HelloWorldCallback.h

  1. 使用hidl-gen生成helloworld/1.0/default/Android.bp
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$ hidl-gen -o vendor/sample/hardware/interfaces/helloworld/1.0/default -Landroidbp-impl -rsample.hardware:vendor/sample/hardware/interfaces -randroid.hidl:system/libhidl/transport [email protected]

  1. 使用system/tools/hidl/update-makefiles-helper.sh生成helloworld/1.0/Android.bp
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$ source $ANDROID_BUILD_TOP/system/tools/hidl/update-makefiles-helper.sh
$ do_makefiles_update sample.hardware:vendor/sample/hardware/interfaces android.hardware:hardware/interfaces android.hidl:system/libhidl/transport

helloworld/1.0/Android.bp内容如下:

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// This file is autogenerated by hidl-gen -Landroidbp.

hidl_interface {
    name: "[email protected]",
    root: "sample.hardware",
    srcs: [
        "types.hal",
        "IHelloWorld.hal",
        "IHelloWorldCallback.hal",
    ],
    interfaces: [
        "[email protected]",
    ],
    types: [
        "Event",
        "Result",
    ],
    gen_java: true,
}
  1. 为device manifest添加hal接口
    由hwservicemanager去解析并将服务启动;
    device/rockchip/$TARGET_PRODUCT/manifest.xml
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    <hal format="hidl">
        <name>sample.hardware.helloworld</name>
        <transport>hwbinder</transport>
        <version>1.0</version>
        <interface>
            <name>IHelloWorld</name>
            <instance>default</instance>
        </interface>
    </hal>

然后完整编译一下Android,更新manifest.xml文件:

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out/target/product/$TARGET_PRODUCT/vendor/etc/vintf/manifest.xml

如果不更新device manifest,测试程序会找不到服务端,hwservicemanager会报以下错误:
W hwservicemanager: getTransport: Cannot find entry [email protected]::IHelloWorld/default in either framework or device manifest.

2. 修改代码

2.1 创建service代码

hardware/interfaces/sample/1.0/default/service.cpp

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#define LOG_TAG "[email protected]"

#include <android-base/logging.h>
#include <hidl/HidlTransportSupport.h>

#include "HelloWorld.h"

using android::OK;
using android::sp;
using android::status_t;
using android::hardware::configureRpcThreadpool;
using android::hardware::joinRpcThreadpool;
using sample::hardware::helloworld::V1_0::IHelloWorld;
using sample::hardware::helloworld::V1_0::implementation::HelloWorld;

int main(int /* argc */, char ** /* argv */)
{
    ALOGD("HAL Service is starting.");
    sp<IHelloWorld> service = new HelloWorld();

    configureRpcThreadpool(1, true /*callerWillJoin*/);
    status_t status = service->registerAsService();
    if (status != OK)
    {
        LOG_ALWAYS_FATAL("Could not register service for HelloWorld HAL Iface (%d).", status);
        return -1;
    }

    ALOGD("Register as service ready.");

    joinRpcThreadpool();
    return 1; // joinRpcThreadpool shouldn't exit
}

2.2 修改Android.bp添加编译service

hardware/interfaces/sample/1.0/default/Android.bp
将cc_library_shared节点proprietary: true改为vendor: true;
删除relative_install_path: “hw”,目的是将[email protected]编译安装到vendor/lib64目录下面,如果vendor/lib64/hw下面,运行服务时因VNDK规则限制,会报以下错误:

F linker : CANNOT LINK EXECUTABLE “./vendor/bin/hw/[email protected]”: library “[email protected]” not found

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cc_library_shared {
    name: "[email protected]",

    vendor: true,
    srcs: [
        "HelloWorld.cpp",
    ],
    shared_libs: [
        "liblog",
        "libhidlbase",
        "libhidltransport",
        "libutils",
        "[email protected]",
    ],
}

cc_binary {
    name: "[email protected]",
    defaults: ["hidl_defaults"],
    vendor: true,
    relative_install_path: "hw",
    init_rc: ["[email protected]"],
    srcs: ["service.cpp"],

    shared_libs: [
        "libcutils",
        "libhidlbase",
        "libhidltransport",
        "liblog",
        "libutils",
        "libhardware",
        "[email protected]",
        "[email protected]",
    ],
}

2.3 添加启动service的init.rc文件

hardware/interfaces/sample/1.0/default/[email protected]

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service vendor.helloworld-1-0 /vendor/bin/hw/[email protected]
    class hal
    user system
    group system

2.4 修改生成的代码

helloworld/1.0/default/HelloWorld.h

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#ifndef SAMPLE_HARDWARE_HELLOWORLD_V1_0_HELLOWORLD_H
#define SAMPLE_HARDWARE_HELLOWORLD_V1_0_HELLOWORLD_H

#include <sample/hardware/helloworld/1.0/IHelloWorld.h>
#include <hidl/MQDescriptor.h>
#include <hidl/Status.h>

namespace sample {
namespace hardware {
namespace helloworld {
namespace V1_0 {
namespace implementation {

using ::android::hardware::hidl_array;
using ::android::hardware::hidl_memory;
using ::android::hardware::hidl_string;
using ::android::hardware::hidl_vec;
using ::android::hardware::Return;
using ::android::hardware::Void;
using ::android::sp;

struct HelloWorld : public IHelloWorld
{
    Return<void> initial() override;
    Return<int32_t> getInt() override;
    Return<::sample::hardware::helloworld::V1_0::Result> setInt(int32_t val) override;
    Return<void> setCallback(const sp<::sample::hardware::helloworld::V1_0::IHelloWorldCallback> &callback) override;

    static void *pollThreadWrapper(void *me);
    void pollThreadEntry();

private:
    pthread_mutex_t mLock = PTHREAD_MUTEX_INITIALIZER;
    pthread_t mPollThread;
    bool mRunning;
    std::vector<sp<IHelloWorldCallback>> mCallbacks;
};

}  // namespace implementation
}  // namespace V1_0
}  // namespace helloworld
}  // namespace hardware
}  // namespace sample

#endif  // SAMPLE_HARDWARE_HELLOWORLD_V1_0_HELLOWORLD_H

helloworld/1.0/default/HelloWorld.cpp

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#define LOG_TAG "[email protected]"
#include <android-base/logging.h>
#include <log/log.h>

#include "HelloWorld.h"

namespace sample {
namespace hardware {
namespace helloworld {
namespace V1_0 {
namespace implementation {

Return<void> HelloWorld::initial()
{
    ALOGD("%s", __FUNCTION__);

    if (mRunning)
        return Void();

    mRunning = true;
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
    pthread_create(&mPollThread, &attr, pollThreadWrapper, this);
    pthread_attr_destroy(&attr);

    return Void();
}

Return<int32_t> HelloWorld::getInt()
{
    ALOGD("%s", __FUNCTION__);
    return int32_t{666};
}

Return<::sample::hardware::helloworld::V1_0::Result> HelloWorld::setInt(int32_t val)
{
    ALOGD("%s %d", __FUNCTION__, val);
    return ::sample::hardware::helloworld::V1_0::Result{};
}

void *HelloWorld::pollThreadWrapper(void *me)
{
    static_cast<HelloWorld *>(me)->pollThreadEntry();
    return NULL;
}

void HelloWorld::pollThreadEntry()
{
    mRunning = true;
    ALOGD("%s enter", __FUNCTION__);

    Event event;
    event.type = 0;
    event.code = 0;
    event.value = 0;
    while (mRunning)
    {
        event.code++;
        event.type++;
        event.value++;
        sleep(1);
        ALOGD("%s event %04x %04x %04x\n", __FUNCTION__, event.type, event.code, event.value);
        pthread_mutex_lock(&mLock);
        if (!mCallbacks.empty())
        {
            std::vector<sp<IHelloWorldCallback>>::iterator it;
            for (it = mCallbacks.begin(); it != mCallbacks.end();)
            {
                sp<IHelloWorldCallback> callback = *it;
                Return<void> ret = callback->onEvent(event);
                if (!ret.isOk())
                {
                    ALOGE("error %s", ret.description().c_str());
                    it = mCallbacks.erase(it);
                }
                else
                {
                    it++;
                }
            }
        }
        pthread_mutex_unlock(&mLock);
    }
    ALOGD("%s exit", __FUNCTION__);
}

Return<void> HelloWorld::setCallback(const sp<::sample::hardware::helloworld::V1_0::IHelloWorldCallback> &callback)
{
    ALOGD("%s", __FUNCTION__);
    pthread_mutex_lock(&mLock);

    if (callback != nullptr)
    {
        mCallbacks.push_back(callback);
    }

    pthread_mutex_unlock(&mLock);
    return Void();
}

}  // namespace implementation
}  // namespace V1_0
}  // namespace helloworld
}  // namespace hardware
}  // namespace sample

2.5 添加本地C++测试代码

helloworld/1.0/test/Android.bp

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cc_binary {
    name: "sample.hardware.helloworld_hidl_hal_test",
    vendor: true,
    srcs: ["test.cpp"],

    shared_libs: [
        "libhidlbase",
        "libhidltransport",
        "liblog",
        "libutils",
        "libhardware",
        "[email protected]",
    ],
}

helloworld/1.0/test/test.cpp

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#define LOG_TAG "sample.hardware.helloworld_hidl_hal_test"

#include <android-base/logging.h>
#include <hidl/HidlTransportSupport.h>
#include <log/log.h>
#include <sample/hardware/helloworld/1.0/IHelloWorld.h>
#include <sample/hardware/helloworld/1.0/types.h>

using ::android::sp;
using ::android::hardware::Return;
using ::android::hardware::Void;
using ::sample::hardware::helloworld::V1_0::Event;
using ::sample::hardware::helloworld::V1_0::IHelloWorld;
using ::sample::hardware::helloworld::V1_0::IHelloWorldCallback;
using ::sample::hardware::helloworld::V1_0::Result;

class HelloWorldCallback : public IHelloWorldCallback
{
public:
    HelloWorldCallback()
    {
        printf("%s\n", __FUNCTION__);
    }
    ~HelloWorldCallback()
    {
        printf("%s\n", __FUNCTION__);
    }

    Return<void> onEvent(const Event &event)
    {
        printf("%s %04x %04x %04x\n", __FUNCTION__, event.type, event.code, event.value);
        return Void();
    }
};

int main(int /* argc */, char ** /* argv */)
{
    sp<IHelloWorld> service = IHelloWorld::getService();
    if (service == nullptr)
    {
        printf("Failed to get service\n");
        return -1;
    }

    printf("initial\n");
    service->initial();

    int ret = service->getInt();
    printf("getInt %d\n", ret);

    Result result = service->setInt(888);
    printf("setInt result=%d\n", result);

    sp<IHelloWorldCallback> callback = new HelloWorldCallback();
    printf("setCallback\n");
    service->setCallback(callback);
    while (1)
    {
        sleep(1);
    }

    return 0;
}

3. 编译测试

3.1 mmm单独模块编译:

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$ mmm vendor/sample/hardware/interfaces/helloworld/1.0/
  1. 编译hal文件生成的中间代码位于out/soong/.intermediates/vendor/sample/hardware/interfaces/helloworld/1.0/:
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default
[email protected]
[email protected]
[email protected]_genc++
[email protected]
[email protected]_genc++
[email protected]_genc++_headers
[email protected]_genc++
[email protected]_genc++_headers
sample.hardware.helloworld-V1.0-java
sample.hardware.helloworld-V1.0-java_gen_java
test

"[email protected]_genc++"目录里面可以发现hal文件转换成了C++源码 ,里面就包含Binder Bn端,Binder Bp端的代码.不用像非Project Treble项目那样需要自己写Binder Bn端,Binder Bp端的代码.体会到了谷歌的良苦用心.

  1. 编译最终会在out/target/product/$TARGET_PRODUCT/目录下面生成了以下文件:
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out/target/product/$TARGET_PRODUCT/system/lib/[email protected]
out/target/product/$TARGET_PRODUCT/system/lib/[email protected]
out/target/product/$TARGET_PRODUCT/system/lib64/[email protected]
out/target/product/$TARGET_PRODUCT/system/lib64/[email protected]
out/target/product/$TARGET_PRODUCT/system/framework/sample.hardware.helloworld-V1.0-java.jar
out/target/product/$TARGET_PRODUCT/system/framework/oat/arm/sample.hardware.helloworld-V1.0-java.odex
out/target/product/$TARGET_PRODUCT/system/framework/oat/arm/sample.hardware.helloworld-V1.0-java.vdex
out/target/product/$TARGET_PRODUCT/system/framework/oat/arm64/sample.hardware.helloworld-V1.0-java.odex
out/target/product/$TARGET_PRODUCT/system/framework/oat/arm64/sample.hardware.helloworld-V1.0-java.vdex
out/target/product/$TARGET_PRODUCT/vendor/lib/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/lib/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/lib/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/lib64/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/lib64/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/lib64/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/bin/hw/[email protected]
out/target/product/$TARGET_PRODUCT/vendor/bin/sample.hardware.helloworld_hidl_hal_test
out/target/product/$TARGET_PRODUCT/vendor/etc/init/[email protected]

3.2 Native测试

  1. 将编译好的库和bin文件复制到设备中:
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$ adb root
$ adb remount
$ adb push  out/target/product/$TARGET_PRODUCT/vendor/lib64/[email protected] /vendor/lib64/[email protected]
$ adb push  out/target/product/$TARGET_PRODUCT/vendor/lib64/[email protected] /vendor/lib64/[email protected]
$ adb push  out/target/product/$TARGET_PRODUCT/vendor/bin/hw/[email protected] /vendor/bin/hw/[email protected]
$ adb push  out/target/product/$TARGET_PRODUCT/vendor/bin/sample.hardware.helloworld_hidl_hal_test /vendor/bin/sample.hardware.helloworld_hidl_hal_test
  1. 启动服务和测试
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# ./vendor/bin/hw/[email protected]&
# sample.hardware.helloworld_hidl_hal_test                      
initial
getInt 666
setInt result=0
HelloWorldCallback
setCallback
onEvent 0001 0001 0001
onEvent 0002 0002 0002
onEvent 0003 0003 0003

3.3 Android APP java测试

Android Studio中将out/soong/.intermediates/vendor/sample/hardware/interfaces/helloworld/1.0/sample.hardware.helloworld-V1.0-java/android_common/combined/sample.hardware.helloworld-V1.0-java.jar 复制到APP工程的libs目录下面,然后将此jar包导入工程就可以使用了,java使用就是这么简单,连JNI都不用自己写了;
不要用/system/framework/sample.hardware.helloworld-V1.0-java.jar这个jar包,这是Dex优化剥离了class文件后的jar;

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package com.example.helloworld;

import android.app.Activity;
import android.os.Bundle;
import android.os.RemoteException;
import android.util.Log;

import sample.hardware.helloworld.V1_0.Event;
import sample.hardware.helloworld.V1_0.IHelloWorld;
import sample.hardware.helloworld.V1_0.IHelloWorldCallback;

public class MainActivity extends Activity {

    private static final String TAG = MainActivity.class.getSimpleName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        try {
            IHelloWorld helloWorld = IHelloWorld.getService();
            helloWorld.initial();
            int ret = helloWorld.getInt();
            Log.d(TAG, "getInt=" + ret);
            helloWorld.setInt(888);
            helloWorld.setCallback(new HelloWorldCallback());
        } catch (RemoteException e) {
            e.printStackTrace();
        }
    }

    static class HelloWorldCallback extends IHelloWorldCallback.Stub {

        @Override
        public void onEvent(Event event) throws RemoteException {
            Log.d(TAG, "onEvent type=" + event.type + ", code=" + event.code + ", value=" + event.value);
        }
    }
}