jni 创建线程的第二种方式

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我是靠谱客的博主淡淡龙猫，最近开发中收集的这篇文章主要介绍jni 创建线程的第二种方式，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

#include <jni.h>
#include <string>
#include <iostream>
#include <functional>
#include <thread>
#include <memory>
#include <chrono>
#include <pthread.h>
#include "android/log.h"


jobject callback;

#define LOGI(...) __android_log_print(ANDROID_LOG_INFO," jni ",__VA_ARGS__);



void todoLog(JavaVM *vm) {
    JNIEnv *env;
    vm->AttachCurrentThread(&env, nullptr);
    //开始干活
    int counts = 100;
    if (callback == nullptr)return;
    jclass javaClass = env->GetObjectClass(callback);
    if (javaClass == nullptr) {
        return;
    }
    jmethodID javaMethodId = env->GetMethodID(javaClass, "callBack", "(I)V");
    if (javaMethodId == nullptr) {
        return;
    }
    while (counts >= 0) {
        env->CallVoidMethod(callback, javaMethodId, counts);
        counts--;
        std::this_thread::sleep_for(std::chrono::seconds(1));
    }
    env->DeleteGlobalRef(callback);
    env = nullptr;
    callback = nullptr;
    //收尾
    vm->DetachCurrentThread();
}


extern "C"
JNIEXPORT void JNICALL
Java_com_jkkc_myapplication_NativeMethod_setCallBack(JNIEnv *env, jobject thiz, jobject call_back) {
    JavaVM *vm;
    env->GetJavaVM(&vm);
    callback = env->NewGlobalRef(call_back);
    LOGI("主线程在哪个线程%ld", std::this_thread::get_id())
    std::shared_ptr<std::thread> thd_ptr = std::make_shared<std::thread>(todoLog, vm);
    thd_ptr->detach();
}