Android message mechanism (ii)

Message Channel: Looper

First write the Main.xml file

The code is as follows:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android"    xmlns:tools= "http// Schemas.android.com/tools "    android:orientation=" vertical "    android:layout_width=" Fill_parent    " android:layout_height= "Fill_parent" ><textview     android:id= "@+id/info" android:layout_width= "Fill_    Parent "    android:layout_height=" wrap_content "/><button     android:id=" @+id/but "    android:layout_ Width= "Fill_parent"    android:layout_height= "Wrap_content"    

Then rewrite the Activity.java class

The code is as follows:

Package Com.example.myfirstproject;import Java.util.arraylist;import Java.util.list;import java.util.Timer;import Java.util.timertask;import Android.os.bundle;import Android.os.handler;import Android.os.Looper;import Android.os.message;import Android.app.activity;import Android.content.pm.activityinfo;import Android.content.res.configuration;import Android.view.menu;import Android.view.view;import Android.view.view.onclicklistener;import android.view.viewgroup;import android.widget.*;p ublic class MainActivity    Extends Activity {private TextView info;private Button but;private static final int SET = 1;        public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);        Setcontentview (R.layout.activity_main);        This.info = (TextView) Super.findviewbyid (r.id.info);        This.but = (Button) Super.findviewbyid (r.id.but);    This.but.setOnClickListener (New Onclicklistenerlmpl ()); } Private class Onclicklistenerlmpl implements Onclicklistener{public void OnClick (view view) {switch (View.getid ()) {case R.id.but:looper Looper = Looper.mylooper ();    MyHandler MyHandler = new MyHandler (looper);    Myhandler.removemessages (0);    String data = "Hahahaha";    Message msg = Myhandler.obtainmessage (set,1,1,data);    Myhandler.sendmessage (msg);    Break    }}} Private class MyHandler extends handler{public MyHandler (Looper Looper) {super (Looper); } public void Handlemessage (Message msg) {switch (msg.what) {case 1:mainactivity.this.info.settext (Msg.obj.toS    Tring ()); }    }    }}

Operating effect:

Android message mechanism (ii)