广播

1.什么是广播        

2.标准广播

BroadStandardActivity.java

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.view.View;import com.tiger.chapter09.receiver.StandardReceiver;public class BroadStandardActivity extends AppCompatActivity implements View.OnClickListener {    private StandardReceiver standardReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_broad_standard);        findViewById(R.id.btn_send_standard).setOnClickListener(this);    }    @Override    public void onClick(View v) {        //发送标准广播  相当于主题        Intent intent = new Intent(StandardReceiver.STRING);        sendBroadcast(intent);    }    @Override    protected void onStart() {        super.onStart();        standardReceiver = new StandardReceiver();        //代表上下文 注册 广播接收者  相当于订阅        IntentFilter intentFilter = new IntentFilter(StandardReceiver.STRING);        //注册接收器，注册之后才能正常接收广播        registerReceiver(standardReceiver,intentFilter);    }    @Override    protected void onStop() {        super.onStop();        //在Activity不用的时候就不需要 广播订阅了，先注销接收者        unregisterReceiver(standardReceiver);    }}

xml

receiver

package com.tiger.chapter09.receiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;//定义一个标准广播的接收器public class StandardReceiver extends BroadcastReceiver {    public static final String STRING ="com.tiger.chapter09.standard";    //一旦接收到标准广播，马上触发接收器的onReceive方法    @Override    public void onReceive(Context context, Intent intent) {        //先当于订阅主题        if (intent!=null&&intent.getAction().equals(STRING)){            Log.d("ning","收到了标准广播");        }    }}

3.有序广播

 BroadOrderActivity.java

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.view.View;import com.tiger.chapter09.receiver.OrderAReceiver;import com.tiger.chapter09.receiver.OrderBReceiver;public class BroadOrderActivity extends AppCompatActivity implements View.OnClickListener {    public static final String ORDER_ACTION = "com.tiger.chapter09.order";    private OrderAReceiver orderAReceiver;    private OrderBReceiver orderBReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_broad_order);        findViewById(R.id.btn_send_order).setOnClickListener(this);    }    @Override    public void onClick(View v) {        //创建一个指定动作的意图        Intent intent  =new Intent(ORDER_ACTION);        //发送有序广播        sendOrderedBroadcast(intent,null);    }    @Override    protected void onStart() {        super.onStart();        //多个接收器处理有序广播的顺序规则为:        //1.优先级越大的2接收器，越早收到有序广播        //2.优先级相同的时候，越早注册的接收器越早收到有序广播        orderAReceiver = new OrderAReceiver();        IntentFilter filterA = new IntentFilter(ORDER_ACTION);        filterA.setPriority(8);        registerReceiver(orderAReceiver,filterA);        orderBReceiver = new OrderBReceiver();        IntentFilter filterB = new IntentFilter(ORDER_ACTION);        filterB.setPriority(10);        registerReceiver(orderBReceiver,filterB);    }    @Override    protected void onStop() {        super.onStop();        unregisterReceiver(orderAReceiver);        unregisterReceiver(orderBReceiver);    }}

AOrder

package com.tiger.chapter09.receiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;import com.tiger.chapter09.BroadOrderActivity;public class OrderAReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        if (intent!=null&&intent.getAction().equals(BroadOrderActivity.ORDER_ACTION)){            Log.d("ning","接收器A 收到了有序广播");        }    }}

BOrder

package com.tiger.chapter09.receiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;import com.tiger.chapter09.BroadOrderActivity;public class OrderBReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        if (intent!=null&&intent.getAction().equals(BroadOrderActivity.ORDER_ACTION)){            Log.d("ning","接收器B 收到了有序广播");            abortBroadcast();//中断广播，此时后面的接收器无法收到该广播        }    }}

4.广播的静态注册

activity

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.ComponentName;import android.content.Intent;import android.os.Bundle;import android.view.View;import com.tiger.chapter09.receiver.ShockReceiver;public class BroadStaticActivity extends AppCompatActivity implements View.OnClickListener {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_broad_static);        findViewById(R.id.btn_send_shock).setOnClickListener(this);    }    @Override    public void onClick(View v) {        //Android8.0 之后 删除了大部分静态注册，防止退出App后仍在接收广播        //为了让应用能够继续接收静态广播，需要给静态注册的广播指定包名        String fullName = "com.tiger.chapter09.receiver.ShockReceiver";        Intent intent = new Intent(ShockReceiver.SHOCK_ACTION);        ComponentName componentName = new ComponentName(this, fullName);        intent.setComponent(componentName);        sendBroadcast(intent);    }}

 ShockReceiver

package com.tiger.chapter09.receiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.os.VibrationEffect;import android.os.Vibrator;import android.util.Log;public class ShockReceiver extends BroadcastReceiver {    public static final String SHOCK_ACTION="com.jmj.shock";    @Override    public void onReceive(Context context, Intent intent) {        if (intent!=null&&intent.getAction().equals(SHOCK_ACTION)){            Log.d("ning","震动一下");            //从系统服务中获取震动管理器            Vibrator vb = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);            //震动需要权限，开启清单权限就不会报错了                vb.vibrate(VibrationEffect.createOneShot(500,50));        }    }}

清单文件 

5.系统分钟到达广播

Activity

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;public class SystemMinuteActivity extends AppCompatActivity {    private TimeReceiver timeReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_system_minute);    }    @Override    protected void onStart() {        super.onStart();        //创建一个分钟变更的广播接收器        timeReceiver = new TimeReceiver();        IntentFilter filter = new IntentFilter(Intent.ACTION_TIME_TICK);        registerReceiver(timeReceiver,filter);    }    @Override    protected void onStop() {        super.onStop();        unregisterReceiver(timeReceiver);    }}

TimeReceiver

package com.tiger.chapter09;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.util.Log;public class TimeReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        if (intent!=null){            Log.d("ning","收到一个分钟到达广播");        }    }}

6.系统网络变更广播

SystemNetWorkActivity

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import com.tiger.chapter09.receiver.NetWorkReceiver;public class SystemNetWorkActivity extends AppCompatActivity {    private NetWorkReceiver netWorkReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_system_net_work);    }    @Override    protected void onStart() {        super.onStart();        netWorkReceiver = new NetWorkReceiver();        IntentFilter filter = new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE");        registerReceiver(netWorkReceiver,filter);    }    @Override    protected void onStop() {        super.onStop();        unregisterReceiver(netWorkReceiver);    }}

NetWorkReceiver

package com.tiger.chapter09.receiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.net.NetworkInfo;import android.os.Parcelable;import android.util.Log;import com.tiger.chapter09.util.NetworkUtil;public class NetWorkReceiver extends BroadcastReceiver {    @Override    public void onReceive(Context context, Intent intent) {        if (intent != null) {            NetworkInfo networkInfo = intent.getParcelableExtra("networkInfo");            // 收到一个网络变更广播，网络大类为MOBILE，网络小类为HSPA，网络制式为3G，网络状态为DISCONNECTED            // 收到一个网络变更广播，网络大类为WIFI，网络小类为，网络制式为未知，网络状态为CONNECTED            String text = String.format("收到一个网络变更广播，网络大类为%s，" +                            "网络小类为%s，网络制式为%s，网络状态为%s",                    networkInfo.getTypeName(),                    networkInfo.getSubtypeName(),                    NetworkUtil.getNetworkClass(networkInfo.getSubtype()),                    networkInfo.getState().toString());            Log.d("ning", text);        }    }}

NetWorkUtil

package com.tiger.chapter09.util;import android.telephony.TelephonyManager;public class NetworkUtil {    // 获取数据连接的制式类型    public static String getNetworkClass(int subType) {        switch (subType) {            case TelephonyManager.NETWORK_TYPE_GPRS:            case TelephonyManager.NETWORK_TYPE_EDGE:            case TelephonyManager.NETWORK_TYPE_CDMA:            case TelephonyManager.NETWORK_TYPE_1xRTT:            case TelephonyManager.NETWORK_TYPE_IDEN:                return "2G";            case TelephonyManager.NETWORK_TYPE_UMTS:            case TelephonyManager.NETWORK_TYPE_EVDO_0:            case TelephonyManager.NETWORK_TYPE_EVDO_A:            case TelephonyManager.NETWORK_TYPE_HSDPA:            case TelephonyManager.NETWORK_TYPE_HSUPA:            case TelephonyManager.NETWORK_TYPE_HSPA:            case TelephonyManager.NETWORK_TYPE_EVDO_B:            case TelephonyManager.NETWORK_TYPE_EHRPD:            case TelephonyManager.NETWORK_TYPE_HSPAP:                return "3G";            case TelephonyManager.NETWORK_TYPE_LTE:                return "4G";            case TelephonyManager.NETWORK_TYPE_NR:                return "5G";            default:                return "未知";        }    }}

 

7. alarm定时器广播

package com.tiger.chapter09.receiver;import android.app.AlarmManager;import android.app.PendingIntent;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.os.Build;import android.util.Log;public class AlarmReceiver extends BroadcastReceiver {    public static final String ALARM_ACTION="com.tiger.chapter09.alarm";    private Context mContext;    public AlarmReceiver(Context mContext) {        this.mContext = mContext;    }    @Override    public void onReceive(Context context, Intent intent) {        if (intent != null&&intent.getAction().equals(ALARM_ACTION)){            Log.d("ning","收到闹钟广播");            sendAlarm();        }    }    //发送闹钟广播的方法    public void sendAlarm(){        Intent intent = new Intent(ALARM_ACTION);        // 创建一个用于广播的延迟意图        // 针对 S+（版本 10000 及更高版本）要求在创建 PendingIntent 时指定 FLAG_IMMUTABLE 或 FLAG_MUTABLE 之一。        // 强烈考虑使用 FLAG_IMMUTABLE，仅当某些功能依赖于 PendingIntent 是可变的时才使用 FLAG_MUTABLE        PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, 0, intent, PendingIntent.FLAG_IMMUTABLE);        // 从系统服务中获取闹钟管理器        AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){            // 允许在空闲时发送广播，Android6.0之后新增的方法            alarmManager.setAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, 1000, pendingIntent);        }else{            // 设置一次性闹钟，延迟若干秒后，携带延迟意图发送闹钟广播（但Android6.0之后，set方法在暗屏时不保证发送广播，            // 必须调用setAndAllowWhileIdle方法）            alarmManager.set(AlarmManager.RTC_WAKEUP, 1000, pendingIntent);        }        // 设置重复闹钟，每隔一定间隔就发送闹钟广播（但从Android4.4开始，setRepeating方法不保证按时发送广播）//        alarmMgr.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(),//                1000, pIntent);    }}

package com.tiger.chapter09;import androidx.appcompat.app.AppCompatActivity;import android.content.IntentFilter;import android.os.Bundle;import android.view.View;import com.tiger.chapter09.receiver.AlarmReceiver;public class AlarmActivity extends AppCompatActivity implements View.OnClickListener {    private AlarmReceiver alarmReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_alarm);        findViewById(R.id.btn_alarm).setOnClickListener(this);    }    @Override    public void onClick(View v) {        alarmReceiver.sendAlarm();    }    @Override    protected void onStart() {        super.onStart();        alarmReceiver = new AlarmReceiver(getApplicationContext());        IntentFilter filter = new IntentFilter(AlarmReceiver.ALARM_ACTION);        registerReceiver(alarmReceiver,filter);    }    @Override    protected void onStop() {        super.onStop();        unregisterReceiver(alarmReceiver);    }}

8.竖屏与横屏切换

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package com.tiger.chapter09;import androidx.annotation.NonNull;import androidx.appcompat.app.AppCompatActivity;import android.content.res.Configuration;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.TextView;public class ChangeDirectionActivity extends AppCompatActivity {    private TextView tv_monitor;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_change_direction);        tv_monitor = findViewById(R.id.tv_monitor);        Log.d("ning","onCreate");//只执行一次，在屏幕旋转之后    }    //在配置项变更是触发。比如屏幕方向发生变更等等    @Override    public void onConfigurationChanged(@NonNull Configuration newConfig) {        super.onConfigurationChanged(newConfig);        switch (newConfig.orientation){            case Configuration.ORIENTATION_PORTRAIT:                tv_monitor.setText("当前屏幕为竖屏方向");                break;            case Configuration.ORIENTATION_LANDSCAPE:                tv_monitor.setText("当前屏幕为横屏方向");                break;            default:                break;        }    }}

设置只能竖屏或者横屏

screenOrientation = portrait | landscape

9.回到桌面和使用任务列表

package com.tiger.chapter09;import androidx.annotation.NonNull;import androidx.appcompat.app.AppCompatActivity;import android.app.PictureInPictureParams;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.content.res.Configuration;import android.os.Build;import android.os.Bundle;import android.text.TextUtils;import android.util.Log;import android.util.Rational;public class ReturnDesktopActivity extends AppCompatActivity {    private DesktopReceiver desktopReceiver;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_return_desktop);    //因为按了Home或任务键 所以要在onCreate 和 Destroy 来注册 广播 要不然，stop就监听不到了        desktopReceiver = new DesktopReceiver();        IntentFilter filter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);        registerReceiver(desktopReceiver,filter);    }    @Override    protected void onDestroy() {        super.onDestroy();        unregisterReceiver(desktopReceiver);    }    //在进入画中画模式或退出画中画模式时触发    @Override    public void onPictureInPictureModeChanged(boolean isInPictureInPictureMode, @NonNull Configuration newConfig) {        super.onPictureInPictureModeChanged(isInPictureInPictureMode, newConfig);        if (isInPictureInPictureMode){            //进入了画中画模式            Log.d("ning","进入了画中画模式");        }else {            //退出了画中画模式            Log.d("ning","退出了画中画模式");        }    }    //定义一个返回到桌面的广播接收器    private class DesktopReceiver extends BroadcastReceiver {        @Override        public void onReceive(Context context, Intent intent) {            if (intent != null && intent.getAction().equals(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)) {                //回到桌面或者切换到任务列表的主题广播                String reason = intent.getStringExtra("reason");                if (!TextUtils.isEmpty(reason)                        && (reason.equals("homekey") || reason.equals("recentapps"))) {                    //Android 8.0 开始才提供画中画模式                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O && !isInPictureInPictureMode()) {                        //进入画中画模式 创建画中画模式的参数构造器                        PictureInPictureParams.Builder builder = new PictureInPictureParams.Builder();                        //设置宽高比例值，第一个参数表示分子，第二个参数表示分母                        // 下面的10/5 =2，表示画中画窗口的宽度是高度的两倍                        Rational rational = new Rational(10, 5);//宽 高 10 : 5                        builder.setAspectRatio(rational);                        //进入画中画模式                        enterPictureInPictureMode(builder.build());                    }                }            }        }    }}

清单文件 开启画中画支持