handler中post和send方式的区别

1、从用法上

send：发送的是Message

post：发送的是Runnable对象

具体用法，如下代码演示：

MainActivity.java

public class MainActivity extends AppCompatActivity {

private TextView textView;

private static final int SEND_UPDATA_TEXT=0;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

textView = findViewById(R.id.tv);

}

private Handler handler = new Handler(){

@Override

public void handleMessage(Message msg) {

switch (msg.what){

case SEND_UPDATA_TEXT:

textView.setText("send");

break;

default:

break;

}

}

};

//send方式发送消息

public void send(View view){

Message message = new Message();

message.what = SEND_UPDATA_TEXT;

handler.sendMessage(message);

}

//post方式发送消息

public void post(View view){

handler.post(new Runnable() {

@Override

public void run() {

textView.setText("post");

}

});

}

}

activity_main.xml

2、原理实现上

下面这篇文章讲的不错

https://www.jianshu.com/p/43d6cd7b06f1