EventBus广播
第一步:添加依赖
compile 'org.greenrobot:eventbus:3.0.0'
第二步:定义消息事件类
public class MessageEvent{
private String message;
public MessageEvent(String message){
this.message=message;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
第三步:注册和解除注册
分别在FirstActivity的onCreate()方法和onDestory()方法里,进行注册EventBus和解除注册。
package com.example.lenovo.testapp.ui;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import com.example.lenovo.testapp.R;
import com.example.lenovo.testapp.event.MessageEvent;
import org.greenrobot.eventbus.EventBus;
import org.greenrobot.eventbus.Subscribe;
import org.greenrobot.eventbus.ThreadMode;
/**
* Created by ZZG on 2018/1/10.
*/
public class FirstActivity extends AppCompatActivity {
private Button mButton;
private TextView mText;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.first_activity);
mButton = (Button) findViewById(R.id.btn1);
mText = (TextView) findViewById(R.id.tv1);
mText.setText("今天是星期三");
EventBus.getDefault().register(this);
jumpActivity();
}
private void jumpActivity() {
mButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent=new Intent(FirstActivity.this,SecondActivity.class);
startActivity(intent);
}
});
}
@Subscribe(threadMode = ThreadMode.MAIN)
public void Event(MessageEvent messageEvent) {
mText.setText(messageEvent.getMessage());
}
@Override
protected void onDestroy() {
super.onDestroy();
if(EventBus.getDefault().isRegistered(this)) {
EventBus.getDefault().unregister(this);
}
}
}
事件处理
在这里,事件的处理线程在主线程,是因为,我要让TextView去显示值。
在 SecondActivity里去进行事件的发送。
package com.example.lenovo.tezs;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import org.greenrobot.eventbus.EventBus;
/**
* Created by ZZG on 2018/1/10.
*/
public class SecondActivity extends AppCompatActivity {
private Button mButton2;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second_activity);
mButton2=(Button) findViewById(R.id.btn2);
jumpActivity();
}
private void jumpActivity() {
mButton2.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
EventBus.getDefault().post(new MessageEvent("欢迎大家浏览我写的博客"));
finish();
}
});
}
}
很简单,当点击按钮的时候,发送了一个事件。