Specific steps:
1. Initialize the broadcast receiver Broadcastreceiver, and the received broadcast will be recalled in the OnReceive method of the class.
2, registered broadcast registerreceiver(broadcastreceiver,intentfilter);
3, send broadcast sendbroadcast (Intent);
This demo is to verify that the activity that has been overwritten can update the UI itself when the broadcast is received, following the specific code:
The first step is to create the mainactivity and initialize the broadcast receiver Broadcastreceiver, register the broadcast
Public class mainactivity extends appcompatactivity { private textview tiptv; public static final string action_name = "Tag_main"; @Override protected void OnCreate (bundle savedinstancestate) { super.oncreate ( Savedinstancestate); setcontentview (R.layout.activity_main); tipTv = (TextView) findviewbyid (R.ID.TIPTV); findviewbyid (R.ID.GOTOTV). Setonclicklistener (new View.onclicklistener () { @Override public void onclick (View  V)  {   &NBsp; intent intent = new intent (Mainactivity.this, secondactivity.class); startactivityforresult (intent, 100); tiptv.settext ("Waiting to receive broadcast ... "); }     //Registered Radio registerboradcastreceiver (); } //broadcast receiver private BroadcastReceiver mBroadcastReceiver = new Broadcastreceiver () { /** * broadcast receiver, receive the broadcast callback method * @param context * @param intent */ @Override public void onreceive (context context, intent intent) {        LOG.D ("MYP", "=== broadcast callback ==="); String action = Intent.getaction (); if ( Action.equals (action_name)) { //when a broadcast is received, the toast is prompted in the topmost activity, toast. Maketext (mainactivity.this, "Broadcast callback", toast.length_short). Show (); string result = intent.getstringextra ("Yaner"); tiptv.settext (Result); //when a broadcast is received, dialog will receive a broadcast interface prompt and will be hidden with the business logic in that interface, // This shows that when the activity is covered, If the activity business logic is started again, it will execute normally in the activity initdialog (); timer timer = new timer (); timer.schedule (New timertask () { @Override public Void run () { if (dialog != null && dialog.isshowing ()) dialog.dismiss (); } }, 3 * 1000); } } }; Dialog dialog; /** * Initialize pop-up box */ private void initdialog () { dialog = new dialog ( this); dialog.setcontentview (R.layout.view_dialog); dialog.show (); } /** * Registered broadcast */ public void registerboradcastreceiver () { IntentFilter Filer = new intentfilter ();//Filter conditions Filer.addaction (action_name);//Set up a broadcast to registerThe label //registered Radio Registerreceiver (Mbroadcastreceiver, filer);         LOG.D ("MYP", "=== broadcast regist ==="); }}
The second step is to create the secondactivity, and the secondactivity implementation trigger can send the broadcast to
The radio events in Mainactivity.
public class secondactivity extends activity { @Override protected void oncreate (bundle savedinstancestate) { super.oncreate (savedinstancestate); setcontentview (R.layout.activity_second); findviewbyid ( R.ID.BRODCASTBTN). Setonclicklistener (New view.onclicklistener () { @Override public void onclick (VIEW V) { intent mintent = new intent ( Mainactivity.action_name); mintent.putextra ("Yaner", "Receive broadcast success!!! )///When receiving a broadcast, carry data //Send broadcast Sendbroadcast (mintent);   LOG.D ("MYP", "=== broadcast send ==="); } }); }}
XML layout file is relatively simple, it is not given, the effect of running:
1, click the button, Toast prompt in secondactivity directly prompt
2, click the button, in 3 seconds return mainactivity,dialog normal display, 3 seconds after the disappearance
3, after the click button, after 3 seconds to return Mainactivity,dialog has disappeared
Conclusion: The covered activity can update the UI itself when it receives the broadcast
This article is from the "10924237" blog, please be sure to keep this source http://10934237.blog.51cto.com/10924237/1726810
Android Broadcast Demo