package com.itheima74.broadcastbestpractice;
import android.content.Intent;
import android.os.Bundle;
import android.os.SystemClock;
import android.support.v4.content.LocalBroadcastManager;
import android.view.View;
/**
 * 模擬強制下線通知
 * 1.登錄成功后10秒發(fā)送一條本地自定義無序廣播
 * 2.接收到廣播后彈出對話框(不可取消)
 * 3.點擊對話框確定按鈕重新返回登陸界面
 */
public class MainActivity extends BaseActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    // 啟動一個子線程,10秒發(fā)送一條本地無序廣播
    new Thread(new Runnable() {
      @Override
      public void run() {
        SystemClock.sleep(1000 * 10);
        LocalBroadcastManager localBroadcastManager = LocalBroadcastManager.getInstance(getApplicationContext());
        localBroadcastManager.sendBroadcast(new Intent("com.itheima74.broadcastbestpractice.FORCE_OFFLINE"));
      }
    }).start();
  }
  // 點擊按鈕,啟動Main2Activity
  public void click(View view) {
    startActivity(new Intent(this, Main2Activity.class));
  }
}

package com.itheima74.broadcastbestpractice;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;
/**
 * Created by My on 2017/3/6.
 */
public class LoginActivity extends AppCompatActivity {
  private EditText et_username;
  private EditText et_password;
  @Override
  protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);
    et_username = (EditText) findViewById(R.id.et_username);
    et_password = (EditText) findViewById(R.id.et_password);
  }
  // 點擊按鈕,進行登錄
  public void login(View view) {
    String username = et_username.getText().toString().trim();
    String password = et_password.getText().toString().trim();
    if ("admin".equals(username) && "123456".equals(password)) {
      Toast.makeText(this, "login success", Toast.LENGTH_SHORT).show();
      startActivity(new Intent(this, MainActivity.class));
    } else {
      Toast.makeText(this, "login fail", Toast.LENGTH_SHORT).show();
    }
  }
}

package com.itheima74.broadcastbestpractice;
import android.app.AlertDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import java.util.ArrayList;
/**
 * BaseActivity
 * 1.記錄所有新創(chuàng)建的Activity
 * 2.隨時銷毀所有Activity
 * 3.所有子類獲取焦點注冊廣播接收者,失去焦點取消注冊
 * 4.收到強制下線廣播,彈出對話框,結束所有Activity,重新啟動LoginActivity
 * Created by My on 2017/3/6.
 */
public class BaseActivity extends AppCompatActivity {
  protected static ArrayList<BaseActivity> activityList = new ArrayList<>();
  private LocalBroadcastManager localBroadcastManager;
  private OffLineReceiver offLineReceiver;
  private IntentFilter intentFilter;
  @Override
  protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    activityList.add(this);
    Log.d("china", getClass().getSimpleName() + " onCreate activityList.size():" + activityList.size());
    localBroadcastManager = LocalBroadcastManager.getInstance(this);
    offLineReceiver = new OffLineReceiver();
    intentFilter = new IntentFilter("com.itheima74.broadcastbestpractice.FORCE_OFFLINE");
  }
  @Override
  protected void onDestroy() {
    super.onDestroy();
    activityList.remove(this);
    Log.d("china", getClass().getSimpleName() + " onDestroy activityList.size():" + activityList.size());
  }
  // 獲取焦點,注冊廣播接收者
  @Override
  protected void onResume() {
    super.onResume();
    localBroadcastManager.registerReceiver(offLineReceiver, intentFilter);
  }
  // 失去焦點,取消注冊廣播接收者
  @Override
  protected void onPause() {
    super.onPause();
    localBroadcastManager.unregisterReceiver(offLineReceiver);
  }
  protected class OffLineReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(final Context context, Intent intent) {
      // 彈出對話框
      AlertDialog.Builder builder = new AlertDialog.Builder(BaseActivity.this);
      builder.setTitle("Warning");
      builder.setMessage("You are force to be offline,Please try to login again.");
      builder.setCancelable(false);// 不允許back鍵取消
      builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
          BaseActivity.finishAll();
          // 重新啟動LoginActivity,廣播接收者中需要添加任務棧
          Intent intent = new Intent(context, LoginActivity.class);
          intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
          context.startActivity(intent);
        }
      });
      builder.show();
    }
  }
  public static void finishAll() {
    for (BaseActivity baseActivity : activityList) {
      if (!baseActivity.isFinishing()) {
        baseActivity.finish();
      }
    }
  }
}