使用广播实现强制下线功能

清单文件：

<activity android:name=".MainActivity">

</activity>
<activity android:name=".LoginActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

login.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".LoginActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:orientation="horizontal">

        <TextView
            android:layout_width="90dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:textSize="18sp"
            android:text="用户名:"/>

        <EditText
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:id="@+id/account"
            android:layout_weight="1"/>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:orientation="horizontal">

        <TextView
            android:layout_width="90dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:textSize="18sp"
            android:text="密码:"/>

        <EditText
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:id="@+id/pwd"
            android:layout_weight="1"/>
    </LinearLayout>

    <Button
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:id="@+id/login"
        android:text="登陆"/>
</LinearLayout>

main.xml:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/force_offline"
        android:text="退出登录"/>
</LinearLayout>

ActivityCollector:

public class ActivityCollector {
    public static List<Activity> list=new ArrayList<>();

    public static void addActivity(Activity activity){
        list.add(activity);
    }

    public static void removeActivity(Activity activity){
        list.remove(activity);
    }

    public static void finishAll(){
        for (Activity activity:list){
            if (!activity.isFinishing()){
                activity.finish();
            }
        }
        list.clear();
    }
}

BaseActivity:

public class BaseActivity extends AppCompatActivity {

    private ForceOfflineReceiver receiver;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ActivityCollector.addActivity(this);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        ActivityCollector.removeActivity(this);
    }

    @Override
    protected void onResume() {
        super.onResume();
        IntentFilter intentFilter=new IntentFilter();
        intentFilter.addAction("111");
        receiver=new ForceOfflineReceiver();
        registerReceiver(receiver,intentFilter);
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (receiver!=null){
            unregisterReceiver(receiver);
            receiver=null;
        }
    }

    public class ForceOfflineReceiver extends BroadcastReceiver{

        @Override
        public void onReceive(final Context context, Intent intent) {
            AlertDialog.Builder builder=new AlertDialog.Builder(context);
            builder.setTitle("错误");
            builder.setMessage("您已经被强制下线");
            builder.setCancelable(false);
            builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    ActivityCollector.finishAll();
                    Intent intent1=new Intent(context,LoginActivity.class);
                    context.startActivity(intent1);
                }
            });
            builder.show();
        }
    }
}

LoginActivity:

public class LoginActivity extends BaseActivity {
    private EditText accountEdittext;
    private EditText pwdEdittext;
    private Button login;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_login);
        accountEdittext=findViewById(R.id.account);
        pwdEdittext=findViewById(R.id.pwd);
        login=findViewById(R.id.login);

        login.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String account=accountEdittext.getText().toString();
                String pwd=pwdEdittext.getText().toString();
                if (account.equals("admin")&&pwd.equals("123456")){
                    startActivity(new Intent(LoginActivity.this,MainActivity.class));
                }else {
                    Toast.makeText(LoginActivity.this,"用户名或密码错误",Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

MainActivity:

public class MainActivity extends BaseActivity {

    private Button forceOffline;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        forceOffline=findViewById(R.id.force_offline);
        forceOffline.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent=new Intent("111");
                sendBroadcast(intent);
            }
        });
    }
}