Xamarin Android:从Service或Receiver更改UI TextView文本

问题描述

我已经使用Twilio api调用了应用程序，并且在服务建立后我试图更改状态TextView文本，我搜索了很多内容，但是找不到任何有用的解决方案，我想从服务中更改文本或广播接收者 .我的服务代码如下:

I have calling app using Twilio api, and i'm trying to change status TextView text after the service established, i searched to much but i didn't find any helpful solution, i want change the text from the service or broadcast receiver .My service code below :

  [Service]
    class CallService : IntentService
    {


        public static  MonkeyPhone phone ;

        protected override void OnHandleIntent(Intent intent)
        {
            throw new NotImplementedException();
        }

        public override StartCommandResult OnStartCommand(Intent intent, StartCommandFlags flags, int startId)
        {

            // countine
            new Task(() =>
            {
                phone = new MonkeyPhone(ApplicationContext);


                 View view = View.Inflate(ApplicationContext, Resource.Layout.Main, null);
                TextView connectionStatus = view.FindViewById<TextView>(Resource.Id.connectionStatus);
                connectionStatus.Text = "Connected ..";

            }).Start();



            return StartCommandResult.Sticky;
        }


    }

服务运行良好，电话连接建立良好，只需要知道如何更改textView文本

The service working well and the phone connect is established well, just need to know how could i change the textView text

注意:textView在片段内部

Attention : the textView is inside fragment

推荐答案

首先，您需要在Receiver中实现此功能，而不是在Service中实现.

First of all, you need to implement this feature in Receiver, not in Service.

在您的服务中，您应该能够发送这样的文本:

In your service, you should be able to send text for example like this:

[Service]
public class MyIntentService : IntentService
{
    public MyIntentService() : base("MyIntentService")
    {
    }

    protected override void OnHandleIntent(Intent intent)
    {
        //get data when service started.
        var value = intent.GetStringExtra("ServiceInfo");

        //send data to activity
        Intent myintent = new Intent("IntentServiceAndReceiver");
        myintent.PutExtra("NewInfo", "Connected...!");
        SendBroadcast(myintent);
    }
}

并创建您的 Receiver 和 MainActivity ，例如:

公共类MainActivity:活动{私人MyReceiver接收器；

public class MainActivity : Activity{ private MyReceiver receiver;

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

    receiver = new MyReceiver(this);

    // Set our view from the "main" layout resource
    SetContentView(Resource.Layout.Main);

    //show fragment in framelayout container
    FragmentTransaction ft = this.FragmentManager.BeginTransaction();
    var myfragment = new MyFragment();
    ft.Add(Resource.Id.container, myfragment).AddToBackStack(null).Commit();
}

protected override void OnResume()
{
    base.OnResume();
    RegisterReceiver(receiver, new IntentFilter("IntentServiceAndReceiver"));
}

protected override void OnPause()
{
    UnregisterReceiver(receiver);
    base.OnPause();
}

    [BroadcastReceiver(Enabled = true, Exported = false)]
    [IntentFilter(new[] { "IntentServiceAndReceiver" })]

    public class MyReceiver : BroadcastReceiver
    {
        private Activity mactivity;

        public MyReceiver()
        {
        }

        public MyReceiver(Activity activity)
        {
            mactivity = activity;
        }

        public override void OnReceive(Context context, Intent intent)
        {
            var value = intent.GetStringExtra("NewInfo");

            //update textview in fragment
            if (mactivity != null)
            {
                var myfragment = mactivity.FragmentManager.FindFragmentById<MyFragment>(Resource.Id.container);
                myfragment.UpdateText(value);
            }
        }
    }
}

我放置了一个 Button 开始服务，并放置了一个 TextView 在 Fragment 的布局中显示文本，如下所示:

I placed a Button to start service and a TextView to show text in the layout of Fragment and code like this:

public class MyFragment : Fragment
{
    private TextView tv;

    public override void OnCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
    }

    public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        // Use this to return your custom view for this Fragment
        var view = inflater.Inflate(Resource.Layout.FLayout, container, false);
        tv = view.FindViewById<TextView>(Resource.Id.tv);
        var btn = view.FindViewById<Button>(Resource.Id.startS);
        btn.Click += (sender, e) =>
        {
            // This code might be called from within an Activity, for example in an event
            // handler for a button click.
            Intent myintent = new Intent(this.Context, typeof(MyIntentService));

            // This is just one example of passing some values to an IntentService via the Intent:
            myintent.PutExtra("ServiceInfo", "This is the information!");

            this.Context.StartService(myintent);
        };
        return view;
    }

    public void UpdateText(string text)
    {
        tv.Text = text;
    }
}

这是结果:

这篇关于Xamarin Android:从Service或Receiver更改UI TextView文本的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！