eventbus使用

1.引入到项目 ：compile 'org.greenrobot:eventbus:3.0.0'

2.原则：先注册，后使用   

EventBus.getDefault().register(this);

@Subscribe

public void onEventMainThread(FirstEvent event) {

    String msg = "onEventMainThread收到了消息：" + event.getMsg();
    Log.d("harvic", msg);

    Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
    bt.setText(msg);
}

3.发送通知

EventBus.getDefault().post(new FirstEvent("FirstEvent btn clicked"));

FirstEvent为自定义 对象

public class MainActivity extends AppCompatActivity {
Button bt;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
            EventBus.getDefault().register(this);
        bt = (Button) findViewById(R.id.bt);
    }

    public void test(View view) {
        startActivity(new Intent(this,SecondActivity.class));
    }
    public void onEventMainThread(FirstEvent event) {

        String msg = "onEventMainThread收到了消息：" + event.getMsg();
        Log.d("harvic", msg);

        Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
        bt.setText(msg);
    }
}

public class SecondActivity extends Activity {
    private TextView tv;
    private Button bt;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.test);

        bt = (Button) findViewById(R.id.bt_jump);
        bt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
//                startActivity(new Intent(SecondActivity.this,MainActivity.class));
                EventBus.getDefault().post(new FirstEvent("FirstEvent btn clicked"));
            }
        });
        tv = (TextView) findViewById(R.id.tv);
    }


    @Override
    protected void onDestroy() {
        super.onDestroy();

    }





}

public class FirstEvent {

   private String mMsg;
   public FirstEvent(String msg) {
      // TODO Auto-generated constructor stub
      mMsg = msg;
   }
   public String getMsg(){
      return mMsg;
   }

案例：