This is an introduction

Part1:Adding the new icon to the application

I choose the origin icons because I think it's ok

Part2:Adding the blue background

revise shape.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">
    <solid android:color="#31a7dc" />
    <size
        android:width="15dp"
        android:height="15dp" />
</shape>

some layout change:

<TextView
    android:id="@+id/textView"
    android:layout_width="63dp"
    android:layout_height="60dp"
    android:background="@drawable/b
    android:gravity="center"
    android:text="mon"
    android:textAllCaps="true"
    android:textColor="#909090" />

Part3:Adding the refresh button.

some layout change:

<ImageView
    android:id="@+id/refresh"
    android:layout_width="48dp"    android:layout_height="48dp"
    android:layout_alignBottom="@+id/linearLayout"
    android:layout_gravity="center"
    android:layout_marginBottom="16dp"
    android:layout_marginEnd="74dp"
    android:layout_marginRight="74dp"
    android:layout_toLeftOf="@+id/tv_temperature"
    android:layout_toStartOf="@+id/tv_temperature"
    android:onClick="btnClick"
    app:srcCompat="@drawable/available_updates"/>

Part4:Adding the Message response

revise in Mainactivity:

public void btnClick(View view) {
   Calendar calendar = Calendar.getInstance();//获取系统的日期
   int year = calendar.get(Calendar.YEAR);//年
   int month = calendar.get(Calendar.MONTH);//月
   int day = calendar.get(Calendar.DAY_OF_MONTH);//日
   int day_of_week =calendar.get(Calendar.DAY_OF_WEEK);//星期
   String[] weeks = {"SUNDAY","MONDAY","TUESDAY","WEDNESDAY","THURSDAY","FRIDAY","SATUR
   ((TextView) findViewById(R.id.dayoftheweek)).setText(weeks[day_of_week-1]);
   ((TextView) findViewById(R.id.tv_date)).setText((month+1)+"/"+day+"/"+year);
   new DownloadUpdate().execute();
}
private class DownloadUpdate extends AsyncTask<String, Void, String> {
   @Override
   protected String doInBackground(String... strings) {
       String stringUrl = "http://mpianatra.com/Courses/info.txt";
       HttpURLConnection urlConnection = null;
       BufferedReader reader;
       try {
           URL url = new URL(stringUrl);
           // Create the request to get the information from the server, and open the c
           urlConnection = (HttpURLConnection) url.openConnection();
           urlConnection.setRequestMethod("GET");
           urlConnection.connect();
           // Read the input stream into a String
           InputStream inputStream = urlConnection.getInputStream();
           StringBuffer buffer = new StringBuffer();
           if (inputStream == null) {
               // Nothing to do.
               return null;
           }
           reader = new BufferedReader(new InputStreamReader(inputStream));
           String line;
           while ((line = reader.readLine()) != null) {
               // Mainly needed for debugging
               buffer.append(line + "\n");
           }
           if (buffer.length() == 0) {
               // Stream was empty.  No point in parsing.
               return null;
           }
           //The temperature
           return buffer.toString();
       } catch (MalformedURLException e) {
           e.printStackTrace();
       } catch (ProtocolException e) {
           e.printStackTrace();
       } catch (IOException e) {
           e.printStackTrace();
       }
       return null;
   }
   @Override
   protected void onPostExecute(String temperature) {
       //Update the temperature displayed
       ((TextView) findViewById(R.id.temperature_of_the_day)).setText(temperature);
   }
}

Part5:Final effect