android 广播broadcast

动态广播:

情景:

界面1开启定时器,3秒发送一次通知,通知别的注册的页面进行页面刷新

此demo共2页面

界面1:

private CountDownTimer countDownTimer;
    private TextView tv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv = (TextView) findViewById(R.id.tv);

        tv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(MainActivity.this,SecondActivity.class);
                startActivity(intent);
            }
        });

        countDownTimer = new CountDownTimer(99999999,3000) {
            @Override
            public void onTick(long millisUntilFinished) {
                Log.d("MainActivity", "发送成功");
                // 主要广播代码*************
                Intent intent = new Intent();
                intent.setAction("com.broadcast");
                intent.putExtra("name", "" + millisUntilFinished);
                sendBroadcast(intent);
                // 主要广播代码***************
                tv.setText("" + millisUntilFinished);
            }

            @Override
            public void onFinish() {

            }
        };
        countDownTimer.start();
    }

    // 注意在销毁时关闭计时器
    @Override
    protected void onDestroy() {
        super.onDestroy();
        countDownTimer.cancel();
    }

界面2:

public class SecondActivity extends Activity {

    private static TextView tv;
    private InReceiver inReceiver;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.secondlayout);
        tv = (TextView) findViewById(R.id.tv);
        inReceiver = new InReceiver();
//实例化过滤器并设置要过滤的广播
        IntentFilter intentFilter = new IntentFilter("com.broadcast");
        //注册广播
        registerReceiver(inReceiver,intentFilter);
    }

// 注意要取消注册
    @Override
    protected void onDestroy() {
        super.onDestroy();
        unregisterReceiver(inReceiver);
    }

    public class InReceiver extends BroadcastReceiver{
        @Override
        public void onReceive(Context context, Intent intent) {
            String name = intent.getExtras().getString("name");
            Toast.makeText(context, "接收到InReceiver:" + name, Toast.LENGTH_SHORT).show();
            tv.setText(name + "");
        }
    }

}