[安卓開發(fā)] Broadcast 三種廣播的使用總結(jié).doc

安卓開發(fā) Broadcast 三種廣播的使用總結(jié)1、什么是安卓的Broadcast？安卓的四大組件之一，是一種廣泛應(yīng)用在應(yīng)用程序之間傳輸信息的機(jī)制。2、什么是安卓的BroadcastReceiver？是對(duì)發(fā)送出來(lái)的廣播進(jìn)行過(guò)濾接收并響應(yīng)的一類組件，它就是用來(lái)接收來(lái)自系統(tǒng)和應(yīng)用中的廣播。例如系統(tǒng)的廣播有開機(jī)廣播： 系統(tǒng)在開機(jī)時(shí)候會(huì)發(fā)送開機(jī)廣播，程序接收到之后，能進(jìn)行開機(jī)自啟動(dòng)。 網(wǎng)絡(luò)狀態(tài)改變廣播： 3g變wifi、網(wǎng)絡(luò)斷開等。電量改變廣播等等。3、Anroid為什么要這樣設(shè)計(jì)？大大減少開發(fā)工作量和開發(fā)周期 作為開發(fā)者，只需要掌握BroadcastReceiver4、怎么理解Broadcast和BroadcastReceiver ?Broadcast就像現(xiàn)實(shí)中的廣播電臺(tái)，他發(fā)廣播信號(hào)來(lái)，然后我們用收音機(jī)來(lái)接收，然后處理，并且播放出聲音， BroadcastReceiver就相當(dāng)于那臺(tái)收音機(jī)。5、使用方法發(fā)送：把信息裝入一個(gè)Intent對(duì)象(如：Action、Category)，通過(guò)調(diào)相應(yīng)的方法將Intent對(duì)象以廣播的方式發(fā)送出去: sendBroadcast(); sendOrederBroadcast(); sendStickyBroadcast();接收：當(dāng)Intent發(fā)送之后，所有已經(jīng)注冊(cè)receivedBroadcastReceiver會(huì)檢查注冊(cè)時(shí)的IntentFilter是否與發(fā)送的Intent相匹配，若匹配則就會(huì)調(diào)用BroadcastReceiver的onReceiver()方法。所以當(dāng)我們定義一個(gè)BroadcastReceiver的時(shí)候，都需要實(shí)現(xiàn)onReceiver()方法。注意：BroadcastReceiver需要注冊(cè) 靜態(tài)注冊(cè) 代碼動(dòng)態(tài)注冊(cè)6、注意！BroadReceiver生命周期只有十秒左右，不能直接執(zhí)行耗時(shí)操作，不然會(huì)出現(xiàn)ANR(應(yīng)用程序無(wú)響應(yīng))，也不能用子線程來(lái)做，因?yàn)槊看螐V播來(lái)的時(shí)候都會(huì)創(chuàng)建一個(gè)Reveiver對(duì)象，并且調(diào)用onReceiver，執(zhí)行完之后 ，對(duì)象會(huì)立刻被銷毀，子線程也沒了 要做耗時(shí)操作的話，應(yīng)該通過(guò)發(fā)送Intent給Service，由Service來(lái)完成。 動(dòng)態(tài)注冊(cè)廣播接受者的話要在Destory回調(diào)事件進(jìn)行unregister7、廣播的分類普通廣播 (Normal broadcast)所有監(jiān)聽該廣播接受者都可以監(jiān)聽到該廣播同級(jí)別接收先后順序是隨機(jī)的(無(wú)序)級(jí)別低的后收到廣播接收器不能截?cái)鄰V播的繼續(xù)傳播，也不能處理廣播同級(jí)別動(dòng)態(tài)注冊(cè)高于靜態(tài)注冊(cè)有序廣播 (Oredered broadcast)按照接收者的優(yōu)先順序來(lái)接收廣播，優(yōu)先級(jí)別在intent-filter中的priority中聲明，-1000到1000之間，值越大優(yōu)先級(jí)越高，可以終止廣播的繼續(xù)傳播，接受者可以修改intent的內(nèi)容。同級(jí)別接收順序是隨機(jī)的級(jí)別低的后收到能截?cái)鄰V播的繼續(xù)傳播，高級(jí)別的廣播接收器接收廣播后能決定時(shí)候截?cái)唷Ｄ芴幚韽V播同級(jí)別動(dòng)態(tài)注冊(cè)高于靜態(tài)注冊(cè)異步廣播 (粘滯性滯留廣播) ps:已被棄用不能處理結(jié)果給下一個(gè)接收者，無(wú)法終止廣播。一直存在可以先發(fā)送廣播，再注冊(cè)接收器需要在清單文件添加android.permission.BROADCAST_STICKY權(quán)限8、Demo布局actibity_main三個(gè)按鈕： MainActivity.Javapublic class MainActivity extends AppCompatActivity implements View.OnClickListener private Button btOne; private Button btTwo; private Button btThree; MyReiceiverThree myReiceiver = new MyReiceiverThree(); Override protected void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btOne = (Button) findViewById(R.id.bt_one); btTwo = (Button) findViewById(R.id.bt_two); btThree = (Button) findViewById(R.id.bt_three); btOne.setOnClickListener(this); btTwo.setOnClickListener(this); btThree.setOnClickListener(this); /動(dòng)態(tài)注冊(cè)，在當(dāng)前activity的生命周期內(nèi)運(yùn)行 /*IntentFilter filter= new IntentFilter(Config.BC_ONE_ACTION); MyReiceiver myReiceiver = new MyReiceiver(); registerReceiver(myReiceiver,filter);*/ Override public void onClick(View view) Intent intent = new Intent(); switch (view.getId() case R.id.bt_one: /發(fā)送普通廣播 intent.setAction(Config.BC_ONE_ACTION); intent.putExtra(msg,這是普通廣播); sendBroadcast(intent); break; case R.id.bt_two: /有序廣播 intent.setAction(Config.BC_TWO_ACTION); intent.putExtra(msg,這是有序廣播); sendOrderedBroadcast(intent,null); /其中第二個(gè)參數(shù)是設(shè)置權(quán)限，即接收器必須具有相應(yīng)的權(quán)限才能正常接收到廣播。 break; case R.id.bt_three: /異步廣播 intent.setAction(Config.BC_THREE_ACTION); intent.putExtra(msg,這是異步廣播); sendStickyBroadcast(intent); /可以先發(fā)送 后注冊(cè) IntentFilter filter = new IntentFilter(Config.BC_THREE_ACTION); registerReceiver(myReiceiver, filter); break; Override protected void onDestroy() super.onDestroy(); unregisterReceiver(myReiceiver); MyReceiver.javapublic class MyReiceiver extends BroadcastReceiver Override public void onReceive(Context context, Intent intent) /獲取處理的的廣播，普通廣播不能獲取處理 /true代表如果前面的接收器沒有存放數(shù)據(jù)，則自動(dòng)創(chuàng)建一個(gè)空的Bundle對(duì)象，false則表示如果前面的接收器如果沒有存放任何數(shù)據(jù)則返回null。 Bundle bundle= getResultExtras(true); System.out.println(接收器1接收到處理的值：+bundle.getString(msg); System.out.println(接收器1：+intent.getStringExtra(msg); MyReceiverTwo.javapublic class MyReiceiverTwo extends BroadcastReceiver Override public void onReceive(Context context, Intent intent) /Toast.makeText(context,intent.getStringExtra(msg),Toast.LENGTH_SHORT).show(); System.out.println(接收器2：+intent.getStringExtra(msg); abortBroadcast(); /截?cái)鄰V播，不讓別的接收器繼續(xù)接收,有序廣播才能成功攔截 /處理廣播 Bundle bundle = new Bundle(); bundle.putString(msg,處理過(guò)后的廣播); setResultExtras(bundle); / MyReceiverThree.javapublic class MyReiceiverThree extends BroadcastReceiver Override public void onReceive(Context context, Intent intent) /Toast.makeText(context,intent.getStringExtra(msg),Toast.LENGTH_SHORT).show(); System.out.println(接收器3：+intent.getStringExtra(msg); Config.javapublic class Config public static final String BC_ONE_ACTION = com.example.testbroadcasetwo.bcone; public static final String BC_TWO_ACTION = com.example.testbroadcasetwo.bctwo; public static final String BC_THREE_ACTION = com.example.testbroadcasetwo.bcthree;Androidmanifest.xml /異步廣播需要 一個(gè)權(quán)限 /靜態(tài)注冊(cè)，全局有效 /第一個(gè)接收器 /添加級(jí)別 /第二個(gè)接收器 /添加級(jí)別 Confiug.java 定義一個(gè)常量作為actionpublic class Config public static String BC_ONE = com.example.testbroadcast.bcone;TYPE.java 枚舉類，集合，沒用了，用來(lái)判斷是什么廣播的public enum TYPE NORMALHandleBroadcas.java p層的處理數(shù)據(jù)類public class HandleBroadcast private IShowView iShowView; private Context context; public HandleBroadcast(final IShowView iShowView, Context context) this.iShowView = iShowView; this.context = context; /必須動(dòng)態(tài)注冊(cè)才能實(shí)現(xiàn)回調(diào) MyBroadcastReceiver broadcast = new MyBroadcastReceiver(); IntentFilter intentFilter = ew IntentFilter(); intentFilter.addAction(Config.BC_ONE); context.registerReceiver(broadcast, intentFilter); broadcast.setiShowView(new IShowView() Override public void updateText(String msg) iShowView.updateText(msg); ); public void sendMyBroadcast(TYPE type) Intent intent = new Intent(); switch (type) case NORMAL: /普通廣播 intent.putExtra(msg, 普通廣播發(fā)送成功); intent.setAction(Config.BC_ONE); context.sendBroadcast(intent); break; MyBroadcast.java 廣播接收器public class MyBroadcastReceiver extends BroadcastReceiver private IShowView iShowView; Override public void onReceive(Context context, Intent intent) String on = intent.getAction(); String msg = intent.getStringExtra(msg); iShowView = (MainActivity) context; if (action.equals(Config.BC_ONE) /接收到普通廣播 iShowView.updateText(msg); /回調(diào)給HandleBroadcast public void setiShowView(IShowView iShowView) this.iShowView = iShowView; IShowView.java 回調(diào)到activity更新ui的接口public interface IShowView void updateText(String msg);MainActivity.javapublicclassMainActivityextendsAppCompatActivityimplements View.OnClickListener,IShowView private Button btOne; private TextView mTvResult; /p層，處理數(shù)據(jù) private HandleBroadcast handleBroadcast; Override p