java.lang.RuntimeException：看起来您正在 Android 上使用 EventBus，请确保将“eventbus”Android 库添加到您的依赖项中

Question

我是这个 EventBus 库的粉丝，并且在其他项目中使用过它，没有遇到任何问题。但是，我目前在活动上注册 EventBus 时遇到了一个奇怪的问题，我陷入了这一点。

java.lang.RuntimeException：看起来您正在 Android 上使用 EventBus，请确保将“eventbus”Android 库添加到您的依赖项中。

我在 BlueStacks 5 和模拟器上都遇到此错误。我已经正确安装了该库，但遇到了这个奇怪的错误。以前有其他人遇到过类似的错误吗？谢谢你。

====================================================== ====

***java.lang.RuntimeException: It looks like you are using EventBus on Android, make sure to add the "eventbus" Android library to your dependencies.
        at org.greenrobot.eventbus.EventBus.register(EventBus.java:145)
        at com.abc.auth.TutorialActivity.onStart(TutorialActivity.java:45)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1425)**
        at android.app.Activity.performStart(Activity.java:7825)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3294)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:221)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)*

====================================================== ==========

package com.abc.auth;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentActivity;
import androidx.viewpager2.adapter.FragmentStateAdapter;
import androidx.viewpager2.widget.ViewPager2;

import android.os.Bundle;
import android.view.View;

import com.abc.databinding.ActivityTutorialBinding;

import org.greenrobot.eventbus.EventBus;
import org.greenrobot.eventbus.Subscribe;
import org.greenrobot.eventbus.ThreadMode;

public class TutorialActivity extends AppCompatActivity {
    private ActivityTutorialBinding binding;

    private static final int NUM_PAGES = 3;
    private ViewPager2 mPager;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        binding = ActivityTutorialBinding.inflate(getLayoutInflater());
        View view = binding.getRoot();
        setContentView(view);

        initComponents();
    }

    void initComponents(){
        mPager = binding.pagerTutorial;
        ScreenSlidePagerAdapter pagerAdapter = new ScreenSlidePagerAdapter(this);
        mPager.setAdapter(pagerAdapter);
    }

    @Override
    protected void onStart() {
        super.onStart();
        EventBus.getDefault().register(this);
    }

    @Override
    protected void onStop() {
        super.onStop();
        EventBus.getDefault().unregister(this);
    }

    @Subscribe(threadMode = ThreadMode.MAIN)
    public void onMessageEvent(MessageEvent event) {
        if (mPager.getCurrentItem() == 2){
            finish();
        }
        else{
            mPager.setCurrentItem(mPager.getCurrentItem() + 1);
        }
    }

    @Override
    public void onBackPressed() {
        if (mPager.getCurrentItem() == 0) {
            super.onBackPressed();
        } else {
            mPager.setCurrentItem(mPager.getCurrentItem() - 1);
        }
    }

    private static class ScreenSlidePagerAdapter extends FragmentStateAdapter {
        public ScreenSlidePagerAdapter(@NonNull AppCompatActivity fragmentActivity) {
            super((FragmentActivity) fragmentActivity);
        }

        @NonNull
        @Override
        public Fragment createFragment(int position) {
            TutorialSlideFragment fragment = new TutorialSlideFragment();
            Bundle args = new Bundle();
            args.putInt("tutorialIndex", position);
            fragment.setArguments(args);

            return fragment;
        }

        @Override
        public int getItemCount() {
            return NUM_PAGES;
        }
    }

    public static class MessageEvent {
        public String msg;

        public MessageEvent(String msg) {
            this.msg = msg;
        }
    }
}

Answer 1

调用

register

时会抛出此异常。这是代码的样子

    if (AndroidDependenciesDetector.isAndroidSDKAvailable() && !AndroidDependenciesDetector.areAndroidComponentsAvailable()) {
        // Crash if the user (developer) has not imported the Android compatibility library.
        throw new RuntimeException("It looks like you are using EventBus on Android, " +
                "make sure to add the \"eventbus\" Android library to your dependencies.");
    }

这让我相信你有这种依赖性

implementation("org.greenrobot:eventbus-java:3.3.1")

而不是这个

Android

implementation("org.greenrobot:eventbus:3.3.1")