Android全局广播和局部广播

一概述

本地广播事件的发送和接收都在本应用，不影响其他应用也不受其他应用影响，只能被动态注册，不能静态注册，主要用法都在LocalBroadcastManager类中，而全局广播则是在Android设备上，主要注册了就都能收到。

使用

1、全局广播Android中使用

布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tvSend"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_marginTop="20dp"
        android:background="#aeaeae"
        android:gravity="center"
        android:text="发送广播"
        android:textColor="#000000" />

    <TextView
        android:id="@+id/tvReceiver"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:gravity="center"
        android:text="展示接受的广播信息"
        android:textColor="#000000" />

</LinearLayout>

Java中发送和注册的代码

public class NormalBroadCastActivity extends Activity {

    private TextView tvReceiver;
    private final String ACTION_TEST = "demos.android.stormdzh.com.androiddemos.broadcast.NormalBroadCastActivity.TestBroadcastReceiver";
    private int index =0;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.adapter_broadcast_normal);

        tvReceiver = findViewById(R.id.tvReceiver);

        findViewById(R.id.tvSend).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                send("参数："+index);
                index++;
            }
        });

        //注册广播
        registerBroadCast();
    }

    private void send(String param) {

        try {
            Intent intent = new Intent();
            intent.putExtra("param", param);
            intent.setAction(ACTION_TEST);
            sendBroadcast(intent);//发送标准广播
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private TestBroadcastReceiver mTestBroadcastReceiver;

    private void registerBroadCast() {
        try {
            //注册点击事件广播
            IntentFilter filter = new IntentFilter(ACTION_TEST);
            filter.setPriority(Integer.MAX_VALUE); //设置级别
            mTestBroadcastReceiver = new TestBroadcastReceiver();
            registerReceiver(mTestBroadcastReceiver, filter);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public class TestBroadcastReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {

            if (intent == null) return;
            if (!TextUtils.equals(intent.getAction(), ACTION_TEST)) {
                return;
            }
            final String param = intent.getStringExtra("param");
            Log.i("dzh", " 广播里面收到参数：" + param);
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    tvReceiver.setText(" 广播里面收到参数：" + param);
                }
            });

        }
    }
}

2、本地广播Android中使用

由于xml文件都是一致的，就不重复写了,核心是使用了LocalBroadcastManager，下面直接贴上java代码

public class LocalBroadCastActivity extends Activity {

    private TextView tvReceiver;
    private final String ACTION_TEST = "demos.android.stormdzh.com.androiddemos.broadcast.NormalBroadCastActivity.TestBroadcastReceiver";
    private int index =0;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.adapter_broadcast_normal);

        tvReceiver = findViewById(R.id.tvReceiver);

        findViewById(R.id.tvSend).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                send("参数："+index);
                index++;
            }
        });

        //注册广播
        registerBroadCast();
    }

    private void send(String param) {

        try {
            Intent intent = new Intent();
            intent.putExtra("param", param);
            intent.setAction(ACTION_TEST);
            LocalBroadcastManager.getInstance(this).sendBroadcast(intent);//发送标准广播
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private TestBroadcastReceiver mTestBroadcastReceiver;

    private void registerBroadCast() {
        try {
            //注册点击事件广播
            IntentFilter filter = new IntentFilter(ACTION_TEST);
            filter.setPriority(Integer.MAX_VALUE); //设置级别
            mTestBroadcastReceiver = new TestBroadcastReceiver();
            LocalBroadcastManager.getInstance(this).registerReceiver(mTestBroadcastReceiver, filter);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public class TestBroadcastReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {

            if (intent == null) return;
            if (!TextUtils.equals(intent.getAction(), ACTION_TEST)) {
                return;
            }
            final String param = intent.getStringExtra("param");
            Log.i("dzh", " 广播里面收到参数：" + param);
            runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    tvReceiver.setText(" 广播里面收到参数：" + param);
                }
            });

        }
    }
}

三、总结

简单的使用就是这么多，接下来有空研究下广播的实现原理。