// 建立廣播
private BroadcastReceiver sendMessage = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        switch (getResultCode()) {
        case Activity.RESULT_OK:
            Toast.makeText(context, "簡訊傳送成功!", Toast.LENGTH_SHORT).show();
            break;
        }
    }
};

    // 動態註冊廣播
    registerReceiver(sendMessage, new IntentFilter("SENT_SMS_ACTION"));
    Intent sentIntent = new Intent("SENT_SMS_ACTION");
    PendingIntent sentPI = PendingIntent.getBroadcast(MainActivity.this, 0, sentIntent, 0);

    // 傳送簡訊，並判斷是否傳送成功
    SmsManager manager = SmsManager.getDefault();
    manager.sendTextMessage(號碼, null, 簡訊內容, sentPI, null);