我想在后台发电子邮件。我在用这个library:library to 实现这一点，所以我用库代码创建了broadcastreceiver。但不幸的是，我在发送电子邮件时出错了-mail:unable to add window——token null无效；你的活动在进行吗？我试图将上下文从活动传递到broadcastreceiver，但我认为receiver中的上下文只是这个语句的一种分离。有什么建议可以避免这个错误吗？
显示

<receiver
        android:name=".service.EmailReceiver"
        android:enabled="true"
        android:exported="true">
        <intent-filter>
            <action android:name="BackgroundProcessEmail" />
        </intent-filter>
    </receiver>

广播接收机

@Override
public void onReceive(final Context context, Intent intent) {

    String email=intent.getStringExtra("email");
    String password=intent.getStringExtra("password");

        String deviceModel = Build.MANUFACTURER
                + " " + Build.MODEL;

        assert email != null;
        assert password != null;
        BackgroundMail.newBuilder(context)
                .withUsername(email)
                .withPassword(password)
                .withSenderName("Full")
                .withMailTo("email")
                .withType(BackgroundMail.TYPE_PLAIN)
                .withSubject("Your device " + deviceModel +" achieved")
                .withBody("")
                .withSendingMessage("Sending email")
                .withOnSuccessCallback(new BackgroundMail.OnSendingCallback() {
                    @Override
                    public void onSuccess() {

                    }

                    @Override
                    public void onFail(Exception e) {

                        Toasty.error(context, "E-mail sent error" + e.getMessage(), Toasty.LENGTH_LONG).show();
                    }
                })
                .send();

}