How to Create and Connect Android App With Laravel API

Author profile picture

@arslanArslan

Full Stack developer /Lead Developer/Project Manager/Software Engineer

The android application market has evolved immersively over the years. It has become the primary source of information and communication not only for the individuals, but also for many companies.
These applications require a significant backend infrastructure to sync their data to and perform functions. That is why many expert app developers recommend a blend of Laravel Android to build a fully functional yet useful application.
One of the best ways to develop a robust backend for your android app is to use the Laravel API on a cloud that does most of the backend processing.
Laravel has a solid codebase and provides optimized performance for all lightweight and enterprise level applications.
In this article, I will first demonstrate you how to create a REST API with Laravel. Then afterwards, I will explain how to create an android app that will interact with the Laravel REST API.

Prerequisites

For the purpose of this blog, I assume that you have a Laravel application installed on a web server. My setup is.
For Android
  • Android Studio
  • Android SDK
For Laravel API
  • Live Web Server
  • Laravel / Lumen 5.6
  • PHP 7.1
  • MySQL
  • Web server (Apache, NGINX or integrated PHP web server for testing)

Set the Database Credentials in .env

First of all, Add those database credentials to the .env file, which is in the application public root folder.
DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE= your.database.name 
DB_USERNAME= your.database.username 
DB_PASSWORD= your.database.password

Create Migration

Now, after successfully connecting to the database, you must develop a migration operator for product table. Once it is up, go to the root of your application with the following commands.
cd applications
cd <yourapplicationname>/public_html
Once you are in the application folder, type the following command to develop the migration operator for the product
php artisan make:migration create_products_table
This will create a <date>_create_table_cars.php file inside the database/migrations/ folder. It is time to edit this file and paste the following code.
<?php

use Illuminate\Support\Facades\Schema;

use Illuminate\Database\Schema\Blueprint;

use Illuminate\Database\Migrations\Migration;



class CreateTableProducts extends Migration

{

   /**

    * Run the migrations.

    *

    * @return void

    */

   public function up()

   {

         Schema::create('products', function (Blueprint $table) {

           $table->increments('pid');

           $table->string('name');

           $table->decimal('price');

           $table->text('description');

           $table->timestamps();

       });

   }



   /**

    * Reverse the migrations.

    *

    * @return void

    */

   public function down()

   {

       //

   }

}
Now that the migration is ready, run the following command to execute the migration.
php artisan migrate
The next step is to migrate the table schema into the database. Go to the database by clicking the Launch Database Manager, and populate the table with dummy data.

Create The Model

Next step is to create the model. Write the following command in the terminal:
php artisan make:model Product
Now go to the app/Product.php file and add the following code:
<?php namespace App;



use Illuminate\Database\Eloquent\Model;

class Product extends Model

{

protected $guarded = [];

}


?>

Create The Controller

Now that the database table is ready, it’s time to develop the controller. Type the following command in your terminal.
php artisan make:controller ProductController
Now go to app/Http/controller/ProductController.php and paste the following code
<?php

namespace App\Http\Controllers;

use App\Product;

use App\Http\Controllers\Controller;

use Illuminate\Http\Request;

use DB;

class ProductController extends Controller{



public function createProduct(Request $request){

    $product = Product::create($request->all());

    return response()->json($product);

}

public function updateProduct(Request $request, $id){



    $product  = DB::table('products')->where('pid',$request->input('pid'))->get();

       $product->name = $request->input('name');

       $product->price = $request->input('price');

       $product->description = $request->input('description');

       $product->save();

       $response["products"] = $product;

       $response["success"] = 1;

    return response()->json($response);

}  



public function deleteProduct($id){

    $product  = DB::table('products')->where('pid',$request->input('pid'))->get();

    $product->delete();

    return response()->json('Removed successfully.');

}



public function index(){

    $products  = Product::all();

       $response["products"] = $products;

       $response["success"] = 1;

    return response()->json($response);

}

}

?>
Now it is time to develop routes. Let’s write routes for creating, updating, deleting and viewing Products.
Open up routes/web.php and add the following routes.
$router->post('product','ProductController@createProduct');   //for creating product

$router->get('product/{id}','ProductController@updateProduct'); //for updating product

$router->post('product/{id}','ProductController@deleteProduct');  // for deleting product

$router->get('product','ProductController@index'); // for retrieving product
Now try accessing all the products via the staging URL. For this, you must go to the application and launch the app using the staging URL.
You will see your data in JSON format
That’s it. The backend Laravel API is ready to deploy in your application.
Now let’s move on to develop an android app and using the API to connect it in our Laravel Server App.

Creating Android Application

  • Download and install Android Studio and Android SDK.
  • Open Android Studio and create a new project.
  • Name the Activity class MainScreenActivity.

Editing the AndroidManifest.xml

Open your AndroidManifest.xml file and add the following code in the manifest tag. Add all the classes and internet connect permission.
<application

  android:allowBackup="true"

  android:icon="@mipmap/ic_launcher"

  android:label="@string/app_name"

  android:roundIcon="@mipmap/ic_launcher_round"

  android:supportsRtl="true"

  android:theme="@style/AppTheme">

  <activity

      android:name=".MainScreenActivity"

      android:label="@string/app_name"

      android:theme="@style/AppTheme.NoActionBar">

      <intent-filter>

          <action android:name="android.intent.action.MAIN" />



          <category android:name="android.intent.category.LAUNCHER" />

      </intent-filter>

  </activity>



  <!-- All Product Activity -->

  <activity

      android:name=".AllProductsActivity"

      android:label="All Products" >

  </activity>



  <!-- Add Product Activity -->

  <activity

      android:name=".NewProductActivity"

      android:label="Add New Product" >

  </activity>



  <!-- Edit Product Activity -->

  <activity

      android:name=".EditProductActivity"

      android:label="Edit Product" >

  </activity>

</application>



<!--  Internet Permissions -->

<uses-permission android:name="android.permission.INTERNET" />

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Creating a JSON Parser Class

Create a new Java class and name it JSONParser.java This class supports two http requests methods GET and POST to get JSON from a URL. Paste the following code in this class.
package com.example.arslan.restapi;



/**

* Created by Arslan.

*/



      import java.io.BufferedReader;

      import java.io.IOException;

      import java.io.InputStream;

      import java.io.InputStreamReader;

      import java.io.UnsupportedEncodingException;

      import java.util.List;



      import org.apache.http.HttpEntity;

      import org.apache.http.HttpResponse;

      import org.apache.http.NameValuePair;

      import org.apache.http.client.ClientProtocolException;

      import org.apache.http.client.entity.UrlEncodedFormEntity;

      import org.apache.http.client.methods.HttpGet;

      import org.apache.http.client.methods.HttpPost;

      import org.apache.http.client.utils.URLEncodedUtils;

      import org.apache.http.impl.client.DefaultHttpClient;

      import org.json.JSONException;

      import org.json.JSONObject;



      import android.util.Log;



public class JSONParser {



  static InputStream is = null;

  static JSONObject jObj = null;

  static String json = "";



  // constructor

  public JSONParser() {



  }



  // function get json from url

  // by making HTTP POST or GET mehtod

  public JSONObject   makeHttpRequest(String url, String method,

                                    List<NameValuePair> params) {



      // Making HTTP request

      try {



          // check for request method

          if(method == "POST"){

              // request method is POST

              // defaultHttpClient

              DefaultHttpClient httpClient = new DefaultHttpClient();

              HttpPost httpPost = new HttpPost(url);

              httpPost.setEntity(new UrlEncodedFormEntity(params));



              HttpResponse httpResponse = httpClient.execute(httpPost);

              HttpEntity httpEntity = httpResponse.getEntity();

              is = httpEntity.getContent();



          }else if(method == "GET"){

              // request method is GET

              DefaultHttpClient httpClient = new DefaultHttpClient();

              String paramString = URLEncodedUtils.format(params, "utf-8");

              url += "?" + paramString;

              HttpGet httpGet = new HttpGet(url);



              HttpResponse httpResponse = httpClient.execute(httpGet);

              HttpEntity httpEntity = httpResponse.getEntity();

              is = httpEntity.getContent();

          }



      } catch (UnsupportedEncodingException e) {

          e.printStackTrace();

      } catch (ClientProtocolException e) {

          e.printStackTrace();

      } catch (IOException e) {

          e.printStackTrace();

      }



      try {

          BufferedReader reader = new BufferedReader(new InputStreamReader(

                  is, "iso-8859-1"), 8);

          StringBuilder sb = new StringBuilder();

          String line = null;

          while ((line = reader.readLine()) != null) {

              sb.append(line + "\n");

          }

          is.close();

          json = sb.toString();

      } catch (Exception e) {

          Log.e("Buffer Error", "Error converting result " + e.toString());

      }



      // try parse the string to a JSON object

      try {

          jObj = new JSONObject(json);

      } catch (JSONException e) {

          Log.e("JSON Parser", "Error parsing data " + e.toString());

      }



      // return JSON String

      return jObj;



  }

}

Creating a Main Screen Layout

Now, you have to develop a new layout file in res/layout/ and name it as main_screen.xml This layout file contains two simple buttons to view all products and add a new product.
<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="fill_parent"

  android:layout_height="fill_parent"

  android:orientation="vertical"

  android:gravity="center_horizontal">



  <!--  Sample Dashboard screen with Two buttons -->

  <!--  Button to view all products screen -->

  <Button android:id="@+id/btnViewProducts"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="View Products"

      android:layout_marginTop="25dip"/>



  <!--  Button to create a new product screen -->

  <Button android:id="@+id/btnCreateProduct"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="Add New Products"

      android:layout_marginTop="25dip"/>



</LinearLayout>

Editing the Main Screen Activity

Open your main activity class, i.e. MainScreenActivity.java and write click events for the two buttons, mentioned in main_screen.xml layout.
package com.example.arslan.restapi;



import android.os.Bundle;

import android.view.View;

import android.view.Menu;

import android.view.MenuItem;

import android.app.Activity;

import android.content.Intent;

import android.widget.Button;



public class MainScreenActivity extends Activity {



  Button btnViewProducts;

  Button btnNewProduct;



  @Override

  public void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.main_screen);

      // Buttons

      btnViewProducts = (Button) findViewById(R.id.btnViewProducts);

      btnNewProduct = (Button) findViewById(R.id.btnCreateProduct);

      // view products click event

      btnViewProducts.setOnClickListener(new View.OnClickListener() {

          @Override

          public void onClick(View view) {

              // Launching All products Activity

              Intent i = new Intent(getApplicationContext(), AllProductsActivity.class);

              startActivity(i);



          }

      });

      // view products click event

      btnNewProduct.setOnClickListener(new View.OnClickListener() {



          @Override

          public void onClick(View view) {

              // Launching create new product activity

              Intent i = new Intent(getApplicationContext(), NewProductActivity.class);

              startActivity(i);



          }

      });

  }



  @Override

  public boolean onCreateOptionsMenu(Menu menu) {

      // Inflate the menu; this adds items to the action bar if it is present.

      getMenuInflater().inflate(R.menu.menu_main_screen, menu);

      return true;

  }



  @Override

  public boolean onOptionsItemSelected(MenuItem item) {

      // Handle action bar item clicks here. The action bar will

      // automatically handle clicks on the Home/Up button, so long

      // as you specify a parent activity in AndroidManifest.xml.

      int id = item.getItemId();



      //noinspection SimplifiableIfStatement

      if (id == R.id.action_settings) {

          return true;

      }



      return super.onOptionsItemSelected(item);

  }

}

Displaying All Products in ListView

You must now develop two xml files under res/layout folder and name them as all_products.xml and list_item.xml
all_products.xml

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="fill_parent"

  android:layout_height="fill_parent"

  android:orientation="vertical">

  <!-- Main ListView

       Always give id value as list(@android:id/list)

  -->

  <ListView

      android:id="@android:id/list"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"/>



</LinearLayout>



List_item.xml



<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="fill_parent"

  android:layout_height="wrap_content"

  android:orientation="vertical" >



  <!-- Product id (pid) - will be HIDDEN - used to pass to other activity -->

  <TextView

      android:id="@+id/pid"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:visibility="gone" />



  <!-- Name Label -->

  <TextView

      android:id="@+id/name"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:paddingTop="6dip"

      android:paddingLeft="6dip"

      android:textSize="17dip"

      android:textStyle="bold" />



</LinearLayout>

Creating the All Products Activity

Then, you must develop a new class file in your Laravel android application and name it as AllProductsActivity.java. In the following code, first a request is sent to the get_all_products.php file using a Background Async task thread.
After getting JSON from get_all_products.php, it is parsed and displayed in a listview. If there are no products found, then it launches AddNewProductAcivity.
package com.example.arslan.restapi;
/**

* Created by arslan.

*/



import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import org.apache.http.NameValuePair;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;



import android.app.ListActivity;

import android.app.ProgressDialog;

import android.content.Intent;

import android.os.AsyncTask;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.widget.AdapterView;

import android.widget.AdapterView.OnItemClickListener;

import android.widget.ListAdapter;

import android.widget.ListView;

import android.widget.SimpleAdapter;

import android.widget.TextView;



public class AllProductsActivity extends ListActivity {



  // Progress Dialog

  private ProgressDialog pDialog;



  // Creating JSON Parser object

  JSONParser jParser = new JSONParser();



  ArrayList<HashMap<String, String>> productsList;



  // url to get all products list

  private static String url_all_products = "http://phplaravel-159494-460027.cloudwaysapps.com/product";



  // JSON Node names

  private static final String TAG_SUCCESS = "success";

  private static final String TAG_PRODUCTS = "products";

  private static final String TAG_PID = "pid";

  private static final String TAG_NAME = "name";



  // products JSONArray

  JSONArray products = null;



  @Override

  public void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.all_products);



      // Hashmap for ListView

      productsList = new ArrayList<HashMap<String, String>>();



      // Loading products in Background Thread

      new LoadAllProducts().execute();



      // Get listview

      ListView lv = getListView();



      // on seleting single product

      // launching Edit Product Screen

      lv.setOnItemClickListener(new OnItemClickListener() {



          @Override

          public void onItemClick(AdapterView<?> parent, View view,

                                  int position, long id) {

              // getting values from selected ListItem

              String pid = ((TextView) view.findViewById(R.id.pid)).getText()

                      .toString();



              // Starting new intent

              Intent in = new Intent(getApplicationContext(),

                      EditProductActivity.class);

              // sending pid to next activity

              in.putExtra(TAG_PID, pid);



              // starting new activity and expecting some response back

              startActivityForResult(in, 100);

          }

      });



  }



  // Response from Edit Product Activity

  @Override

  protected void onActivityResult(int requestCode, int resultCode, Intent data) {

      super.onActivityResult(requestCode, resultCode, data);

      // if result code 100

      if (resultCode == 100) {

          // if result code 100 is received

          // means user edited/deleted product

          // reload this screen again

          Intent intent = getIntent();

          finish();

          startActivity(intent);

      }



  }



  /**

   * Background Async Task to Load all product by making HTTP Request

   * */

  class LoadAllProducts extends AsyncTask<String, String, String> {



      /**

       * Before starting background thread Show Progress Dialog

       * */

      @Override

      protected void onPreExecute() {

          super.onPreExecute();

          pDialog = new ProgressDialog(AllProductsActivity.this);

          pDialog.setMessage("Loading products. Please wait...");

          pDialog.setIndeterminate(false);

          pDialog.setCancelable(false);

          pDialog.show();

      }



      /**

       * getting All products from url

       * */

      protected String doInBackground(String... args) {

          // Building Parameters

          List<NameValuePair> params = new ArrayList<NameValuePair>();

          // getting JSON string from URL

          JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);



          // Check your log cat for JSON reponse

          Log.d("All Products: ", json.toString());



          try {

              // Checking for SUCCESS TAG

              int success = 1;



              if (success == 1) {

                  // products found

                  // Getting Array of Products

                  products = json.getJSONArray(TAG_PRODUCTS);



                  // looping through All Products

                  for (int i = 0; i < products.length(); i++) {

                      JSONObject c = products.getJSONObject(i);



                      // Storing each json item in variable

                      String id = c.getString(TAG_PID);

                      String name = c.getString(TAG_NAME);



                      // creating new HashMap

                      HashMap<String, String> map = new HashMap<String, String>();



                      // adding each child node to HashMap key => value

                      map.put(TAG_PID, id);

                      map.put(TAG_NAME, name);



                      // adding HashList to ArrayList

                      productsList.add(map);

                  }

              } else {

                  // no products found

                  // Launch Add New product Activity

                  Intent i = new Intent(getApplicationContext(),

                          NewProductActivity.class);

                  // Closing all previous activities

                  i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

                  startActivity(i);

              }

          } catch (JSONException e) {

              e.printStackTrace();

          }



          return null;

      }



      /**

       * After completing background task Dismiss the progress dialog

       * **/

      protected void onPostExecute(String file_url) {

          // dismiss the dialog after getting all products

          pDialog.dismiss();

          // updating UI from Background Thread

          runOnUiThread(new Runnable() {

              public void run() {

                  /**

                   * Updating parsed JSON data into ListView

                   * */

                  ListAdapter adapter = new SimpleAdapter(

                          AllProductsActivity.this, productsList,

                          R.layout.list_item, new String[] { TAG_PID,

                          TAG_NAME},

                          new int[] { R.id.pid, R.id.name });

                  // updating listview

                  setListAdapter(adapter);

              }

          });



      }



  }

}

Adding a New Product (Write)

You must also develop a new activity to add a new product into MySQL database. For this, you need to develop a simple form that contains EditText for product name, price and description fields.
Then, create a new xml file and name it as add_product.xml and paste the following code to create a simple form.
<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="match_parent"

  android:layout_height="match_parent"

  android:orientation="vertical" >



  <!-- Name Label -->

  <TextView android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="Product Name"

      android:paddingLeft="10dip"

      android:paddingRight="10dip"

      android:paddingTop="10dip"

      android:textSize="17dip"/>



  <!-- Input Name -->

  <EditText android:id="@+id/inputName"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:layout_margin="5dip"

      android:layout_marginBottom="15dip"

      android:singleLine="true"/>



  <!-- Price Label -->

  <TextView android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="Price"

      android:paddingLeft="10dip"

      android:paddingRight="10dip"

      android:paddingTop="10dip"

      android:textSize="17dip"/>



  <!-- Input Price -->

  <EditText android:id="@+id/inputPrice"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:layout_margin="5dip"

      android:layout_marginBottom="15dip"

      android:singleLine="true"

      android:inputType="numberDecimal"/>



  <!-- Description Label -->

  <TextView android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="Description"

      android:paddingLeft="10dip"

      android:paddingRight="10dip"

      android:paddingTop="10dip"

      android:textSize="17dip"/>



  <!-- Input description -->

  <EditText android:id="@+id/inputDesc"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:layout_margin="5dip"

      android:layout_marginBottom="15dip"

      android:lines="4"

      android:gravity="top"/>



  <!-- Button Create Product -->

  <Button android:id="@+id/btnCreateProduct"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"

      android:text="Create Product"/>



</LinearLayout>

Creating a New Product Activity

Now write the code for New Activity class to insert a new product into MySQL database. For this, you have to create a class file and name it as NewProductActivity.java and type the following code. In the following code, first new product data is read from the EditText form and formatted into a basic param. You must send a request to create_product.php to create a new product through HTTP post.
After getting JSON response from create_product.php, if success bit results into 1 then it refreshes the list view with newly added products.
package com.example.arslan.restapi;



/**

* Created by Arslan.

*/



import java.util.ArrayList;

import java.util.List;



import org.apache.http.NameValuePair;

import org.apache.http.message.BasicNameValuePair;

import org.json.JSONException;

import org.json.JSONObject;



import android.app.Activity;

import android.app.ProgressDialog;

import android.content.Intent;

import android.os.AsyncTask;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;



public class NewProductActivity extends Activity {



  // Progress Dialog

  private ProgressDialog pDialog;



  JSONParser jsonParser = new JSONParser();

  EditText inputName;

  EditText inputPrice;

  EditText inputDesc;



  // url to create new product

  private static String url_create_product = "http://phplaravel-159494-460027.cloudwaysapps.com/product";



  // JSON Node names

  private static final String TAG_SUCCESS = "success";



  @Override

  public void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.add_product);



      // Edit Text

      inputName = (EditText) findViewById(R.id.inputName);

      inputPrice = (EditText) findViewById(R.id.inputPrice);

      inputDesc = (EditText) findViewById(R.id.inputDesc);



      // Create button

      Button btnCreateProduct = (Button) findViewById(R.id.btnCreateProduct);



      // button click event

      btnCreateProduct.setOnClickListener(new View.OnClickListener() {



          @Override

          public void onClick(View view) {

              // creating new product in background thread

              new CreateNewProduct().execute();

          }

      });

  }



  /**

   * Background Async Task to Create new product

   * */

  class CreateNewProduct extends AsyncTask<String, String, String> {



      /**

       * Before starting background thread Show Progress Dialog

       * */

      @Override

      protected void onPreExecute() {

          super.onPreExecute();

          pDialog = new ProgressDialog(NewProductActivity.this);

          pDialog.setMessage("Creating Product..");

          pDialog.setIndeterminate(false);

          pDialog.setCancelable(true);

          pDialog.show();

      }



      /**

       * Creating product

       * */

      protected String doInBackground(String... args) {

          String name = inputName.getText().toString();

          String price = inputPrice.getText().toString();

          String description = inputDesc.getText().toString();



          // Building Parameters

          List<NameValuePair> params = new ArrayList<NameValuePair>();

          params.add(new BasicNameValuePair("name", name));

          params.add(new BasicNameValuePair("price", price));

          params.add(new BasicNameValuePair("description", description));



          // getting JSON Object

          // Note that create product url accepts POST method

          JSONObject json = jsonParser.makeHttpRequest(url_create_product,

                  "POST", params);



          // check log cat fro response

          Log.d("Create Response", json.toString());



          // check for success tag

          try {

              int success = json.getInt(TAG_SUCCESS);



              if (success == 1) {

                  // successfully created product

                  Intent i = new Intent(getApplicationContext(), AllProductsActivity.class);

                  startActivity(i);



                  // closing this screen

                  finish();

              } else {

                  // failed to create product

              }

          } catch (JSONException e) {

              e.printStackTrace();

          }



          return null;

      }



      /**

       * After completing background task Dismiss the progress dialog

       * **/

      protected void onPostExecute(String file_url) {

          // dismiss the dialog once done

          pDialog.dismiss();

    

  }

}

Creating an Edit Product Layout

Navigate to the file AllProductsActivity.java ad you will see that in its listview we are launching EditProductAcivity.java once selecting the single item. So create xml file called edit_product.xml and develop a form which is same as create_product.xml.
<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

  android:layout_width="fill_parent"

  android:layout_height="fill_parent"

  android:orientation="vertical">

  <!-- Main ListView

       Always give id value as list(@android:id/list)

  -->

  <ListView

      android:id="@android:id/list"

      android:layout_width="fill_parent"

      android:layout_height="wrap_content"/>



</LinearLayout>

Creating an Edit Product Activity

Now, you must create a class file for edit_product.xml and name it as EditProductActivity.java and add the following code in it. In this code, first product id (pid) is read from the intent which is sent from listview. A request is made to get_product_details.php and after getting product details in json format, we parse the json and displayed in EditText.
After displaying product data in the form, if user clicks on Save Changes Button, another HTTP request is made to update_product.php to store updated product data.
Meanwhile if the user selects Delete Product Button, HTTP request is made to delete_product.php and it deletes product from MySQL database, and afterwards refreshes the listview with new product list.
package com.example.arslan.restapi;



/**

* Created by Arslan
*/



import java.util.ArrayList;

import java.util.List;



import org.apache.http.NameValuePair;

import org.apache.http.message.BasicNameValuePair;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;



import android.app.Activity;

import android.app.ProgressDialog;

import android.content.Intent;

import android.os.AsyncTask;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;



public class EditProductActivity extends Activity {



  EditText txtName;

  EditText txtPrice;

  EditText txtDesc;

  EditText txtCreatedAt;

  Button btnSave;

  Button btnDelete;



  String pid;



  // Progress Dialog

  private ProgressDialog pDialog;



  // JSON parser class

  JSONParser jsonParser = new JSONParser();



  // single product url

  private static final String url_product_detials = "http://phplaravel-159494-460027.cloudwaysapps.com/product/1";



  // url to update product

  private static final String url_update_product = "http://phplaravel-159494-460027.cloudwaysapps.com/product/1";



  // url to delete product

  private static final String url_delete_product = "http://phplaravel-159494-460027.cloudwaysapps.com/product/1";



  // JSON Node names

  private static final String TAG_SUCCESS = "success";

  private static final String TAG_PRODUCT = "product";

  private static final String TAG_PID = "pid";

  private static final String TAG_NAME = "name";

  private static final String TAG_PRICE = "price";

  private static final String TAG_DESCRIPTION = "description";



  @Override

  public void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.edit_product);



      // save button

      btnSave = (Button) findViewById(R.id.btnSave);

      btnDelete = (Button) findViewById(R.id.btnDelete);



      // getting product details from intent

      Intent i = getIntent();



      // getting product id (pid) from intent

      pid = i.getStringExtra(TAG_PID);



      // Getting complete product details in background thread

      new GetProductDetails().execute();



      // save button click event

      btnSave.setOnClickListener(new View.OnClickListener() {



          @Override

          public void onClick(View arg0) {

              // starting background task to update product

              new SaveProductDetails().execute();

          }

      });



      // Delete button click event

      btnDelete.setOnClickListener(new View.OnClickListener() {



          @Override

          public void onClick(View arg0) {

              // deleting product in background thread

              new DeleteProduct().execute();

          }

      });



  }



  /**

   * Background Async Task to Get complete product details

   * */

  class GetProductDetails extends AsyncTask<String, String, String> {



      /**

       * Before starting background thread Show Progress Dialog

       * */

      @Override

      protected void onPreExecute() {

          super.onPreExecute();

          pDialog = new ProgressDialog(EditProductActivity.this);

          pDialog.setMessage("Loading product details. Please wait...");

          pDialog.setIndeterminate(false);

          pDialog.setCancelable(true);

          pDialog.show();

      }



      /**

       * Getting product details in background thread

       * */

      protected String doInBackground(String... params) {



          // updating UI from Background Thread

          runOnUiThread(new Runnable() {

              public void run() {

                  // Check for success tag

                  int success;

                  try {

                      // Building Parameters

                      List<NameValuePair> params = new ArrayList<NameValuePair>();

                      params.add(new BasicNameValuePair("pid",pid));



                      // getting product details by making HTTP request

                      // Note that product details url will use GET request

                      JSONObject json = jsonParser.makeHttpRequest(

                              url_product_detials, "POST", params);



                      // check your log for json response

                      Log.d("Single Product Details", json.toString());



                      // json success tag

                      success = json.getInt(TAG_SUCCESS);

                      if (success == 1) {

                          // successfully received product details

                          JSONArray productObj = json

                                  .getJSONArray(TAG_PRODUCT); // JSON Array



                          // get first product object from JSON Array

                          JSONObject product = productObj.getJSONObject(0);



                          // product with this pid found

                          // Edit Text

                          txtName = (EditText) findViewById(R.id.inputName);

                          txtPrice = (EditText) findViewById(R.id.inputPrice);

                          txtDesc = (EditText) findViewById(R.id.inputDesc);



                          // display product data in EditText

                          txtName.setText(product.getString(TAG_NAME));

                          txtPrice.setText(product.getString(TAG_PRICE));

                          txtDesc.setText(product.getString(TAG_DESCRIPTION));



                      }else{

                          // product with pid not found

                      }

                  } catch (JSONException e) {

                      e.printStackTrace();

                  }

              }

          });



          return null;

      }



      /**

       * After completing background task Dismiss the progress dialog

       * **/

      protected void onPostExecute(String file_url) {

          // dismiss the dialog once got all details

          pDialog.dismiss();

      }

  }



  /**

   * Background Async Task to  Save product Details

   * */

  class SaveProductDetails extends AsyncTask<String, String, String> {



      /**

       * Before starting background thread Show Progress Dialog

       * */

      @Override

      protected void onPreExecute() {

          super.onPreExecute();

          pDialog = new ProgressDialog(EditProductActivity.this);

          pDialog.setMessage("Saving product ...");

          pDialog.setIndeterminate(false);

          pDialog.setCancelable(true);

          pDialog.show();

      }



      /**

       * Saving product

       * */

      protected String doInBackground(String... args) {



          // getting updated data from EditTexts

          String name = txtName.getText().toString();

          String price = txtPrice.getText().toString();

          String description = txtDesc.getText().toString();



          // Building Parameters

          List<NameValuePair> params = new ArrayList<NameValuePair>();

          params.add(new BasicNameValuePair(TAG_PID, pid));

          params.add(new BasicNameValuePair(TAG_NAME, name));

          params.add(new BasicNameValuePair(TAG_PRICE, price));

          params.add(new BasicNameValuePair(TAG_DESCRIPTION, description));



          // sending modified data through http request

          // Notice that update product url accepts POST method

          JSONObject json = jsonParser.makeHttpRequest(url_update_product,

                  "POST", params);



          // check json success tag

          try {

              int success = json.getInt(TAG_SUCCESS);



              if (success == 1) {

                  // successfully updated

                  Intent i = getIntent();

                  // send result code 100 to notify about product update

                  setResult(100, i);

                  finish();

              } else {

                  // failed to update product

              }

          } catch (JSONException e) {

              e.printStackTrace();

          }



          return null;

      }



      /**

       * After completing background task Dismiss the progress dialog

       * **/

      protected void onPostExecute(String file_url) {

          // dismiss the dialog once product uupdated

          pDialog.dismiss();

      }

  }



  /*****************************************************************

   * Background Async Task to Delete Product

   * */

  class DeleteProduct extends AsyncTask<String, String, String> {



      /**

       * Before starting background thread Show Progress Dialog

       * */

      @Override

      protected void onPreExecute() {

          super.onPreExecute();

          pDialog = new ProgressDialog(EditProductActivity.this);

          pDialog.setMessage("Deleting Product...");

          pDialog.setIndeterminate(false);

          pDialog.setCancelable(true);

          pDialog.show();

      }



      /**

       * Deleting product

       * */

      protected String doInBackground(String... args) {



          // Check for success tag

          int success;

          try {

              // Building Parameters

              List<NameValuePair> params = new ArrayList<NameValuePair>();

              params.add(new BasicNameValuePair("pid", pid));



              // getting product details by making HTTP request

              JSONObject json = jsonParser.makeHttpRequest(

                      url_delete_product, "POST", params);



              // check your log for json response

              Log.d("Delete Product", json.toString());



              // json success tag

              success = json.getInt(TAG_SUCCESS);

              if (success == 1) {

                  // product successfully deleted

                  // notify previous activity by sending code 100

                  Intent i = getIntent();

                  // send result code 100 to notify about product deletion

                  setResult(100, i);

                  finish();

              }

          } catch (JSONException e) {

              e.printStackTrace();

          }



          return null;

      }



      /**

       * After completing background task Dismiss the progress dialog

       * **/

      protected void onPostExecute(String file_url) {

          // dismiss the dialog once product deleted

          pDialog.dismiss();

      }

  }

}

Final Words

In this article, I have demonstrated connection of Android App via Laravel API. The tutorial is quite lengthy and you may get some errors building your Laravel android app. Therefore, I recommend you to recheck the code, as it will surely eradicate those errors.
If you need help in any kind of development project & I can also provide you consultancy about your project. I am top rated freelancer. You can hire me directly on Upwork. You can also hire me on Freelancer.
If you have any comment, question, or recommendation, feel free to post them in the comment section below!

Tags

The Noonification banner

Subscribe to get your daily round-up of top tech stories!