Displaying All Products in ListView (Read)
5. Now we need an Activity display all the products in list view format. As we know list view needs two xml files, one for listview and other is for single list row. Create two xml files under res ⇒ layout folder and name it as all_products.xml and list_item.xml
all_products.xml
<?xml version="1.0" encoding="utf-8"?> 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"?> 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> |
6. Create a new class file and name it as AllProductsActivity.java. In the following code
-> First a request is send to get_all_products.php file using a Background Async task thread.
-> After getting JSON from get_all_products.php, i parsed it and displayed in a listview.
-> If there are no products found AddNewProductAcivity is launched.
-> After getting JSON from get_all_products.php, i parsed it and displayed in a listview.
-> If there are no products found AddNewProductAcivity is launched.
package com.example.androidhive;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 = "https://api.androidhive.info/android_connect/get_all_products.php"; // 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 = json.getInt(TAG_SUCCESS); 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); } }); } }} |