Downloading the file on the button, how do you do?

[elysha]

We need to do this: When the user pushes the button down, the file is downloaded. If there's no Internet, it's a message. How do you do it?

[guilherme]

Create the AppController file.

import android.app.Application;
import android.text.TextUtils;
import com.android.volley.Request;

import com.android.volley.RequestQueue;

import com.android.volley.toolbox.Volley;
public class AppController extends Application {
public static final String TAG = AppController.class.getSimpleName();

private RequestQueue mRequestQueue;

private static AppController mInstance;

@Override
public void onCreate() {
    super.onCreate();
    mInstance = this;
}

public static synchronized AppController getInstance() {
    return mInstance;
}

public RequestQueue getRequestQueue() {
    if (mRequestQueue == null) {
        mRequestQueue = Volley.newRequestQueue(getApplicationContext());
    }

    return mRequestQueue;
}

public <T> void addToRequestQueue(Request<T> req, String tag) {
    req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
    getRequestQueue().add(req);
}

}

Adding to the manifest

<application

android:name=".AppController"

...

/>

B build.gradle add

dependencies {

...

compile 'com.mcxiaoke.volley:library-aar:1.0.0'

}

And finally, it's asynchronous, so you don't have to give him AsyncTask or anything below the line, you can also create a method for another file. http://www.techstricks.com/download-file-using-android-volley ♪

String tag_string_req = "request";

final ProgressDialog progressDialog = new ProgressDialog(getContext());

progressDialog.setMessage("Подключение к серверу. Подождите...");

progressDialog.setIndeterminate(false);

progressDialog.setCancelable(false);

progressDialog.show();

StringRequest strReq = new StringRequest(Request.Method.POST, url,

new Response.Listener<String>() {

@Override

public void onResponse(String response) {

progressDialog.dismiss();

Log.d("response",response);

}, new Response.ErrorListener() {

@Override

public void onErrorResponse(VolleyError error) {

        progressDialog.dismiss();
        AlertDialog.Builder alert = new AlertDialog.Builder(getContext());
        alert.setTitle("Ошибка авторизации");
        final TextView input = new TextView(getContext());
        alert.setView(input);
        input.setTextSize(TypedValue.COMPLEX_UNIT_SP, 17);
        input.setPadding(20, 10, 20, 10);
        input.setTextColor(ContextCompat.getColor(getContext(), android.R.color.black));
        input.setText("Ошибка");
        alert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
            }
        });

        alert.show();
    }
}) {

    @Override
    protected Map&lt;String, String&gt; getParams() {
        //Записываем параметры в запрос который передаем на сервер
        Map&lt;String, String&gt; params = new HashMap&lt;&gt;();
        params.put("param", param);
        return params;
    }

};
AppController.getInstance().addToRequestQueue(strReq, tag_string_req);