Android Populating Spinner data from MySQL Database
Creating Android Project
1. Create a new project in Eclipse from File ⇒ New ⇒ Android Application Project. I had left my main activity name as MainActivity.java and gave the package name as info.androidhive.spinnermysql
2. As this application is going to use internet, we need to add INTERNET permission in AndroidManifest.xml file. Open your AndroidManifest.xml file and add following permission.
<uses-permission android:name=”android.permission.INTERNET”/>
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="info.androidhive.spinnermysql" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="18" /> <!-- Internet Permissions --> <uses-permission android:name="android.permission.INTERNET"/> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="info.androidhive.spinnermysql.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application></manifest>
3. Create a class file named Category.php. This model class will be useful to convert json data into objects.
Category.php
package info.androidhive.spinnermysql;public class Category { private int id; private String name; public Category(){} public Category(int id, String name){ this.id = id; this.name = name; } public void setId(int id){ this.id = id; } public void setName(String name){ this.name = name; } public int getId(){ return this.id; } public String getName(){ return this.name; }}
4. I am creating another class to take care of making API calls and handling the response. Create a class named ServiceHandler.java and write the following code. makeServiceCall() method should be called to make http calls.
ServiceHandler.java
package info.androidhive.spinnermysql;
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 android.util.Log;
public class ServiceHandler {
static InputStream is = null;
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
public ServiceHandler() {
}
/**
* Making service call
* @url - url to make request
* @method - http request method
* */
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/**
* Making service call
* @url - url to make request
* @method - http request method
* @params - http request params
* */
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
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, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
response = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error: " + e.toString());
}
return response;
}
}
5. Now design the interface for your main activity. I have created simple layout to insert new category and a spinner to show the categories fetched from MySQL database. Open activity_main.xml file and insert the following code.
activity_main.xml
Complete Code
MainActivity.java
package info.androidhive.spinnermysql;
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.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnItemSelectedListener {
private Button btnAddNewCategory;
private TextView txtCategory;
private Spinner spinnerFood;
// array list for spinner adapter
private ArrayList<Category> categoriesList;
ProgressDialog pDialog;
// API urls
// Url to create new category
private String URL_NEW_CATEGORY = "http://10.0.2.2/food_api/new_category.php";
// Url to get all categories
private String URL_CATEGORIES = "http://10.0.2.2/food_api/get_categories.php";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnAddNewCategory = (Button) findViewById(R.id.btnAddNewCategory);
spinnerFood = (Spinner) findViewById(R.id.spinFood);
txtCategory = (TextView) findViewById(R.id.txtCategory);
categoriesList = new ArrayList<Category>();
// spinner item select listener
spinnerFood.setOnItemSelectedListener(this);
// Add new category click event
btnAddNewCategory.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (txtCategory.getText().toString().trim().length() > 0) {
// new category name
String newCategory = txtCategory.getText().toString();
// Call Async task to create new category
new AddNewCategory().execute(newCategory);
} else {
Toast.makeText(getApplicationContext(),
"Please enter category name", Toast.LENGTH_SHORT)
.show();
}
}
});
new GetCategories().execute();
}
/**
* Adding spinner data
* */
private void populateSpinner() {
List<String> lables = new ArrayList<String>();
txtCategory.setText("");
for (int i = 0; i < categoriesList.size(); i++) {
lables.add(categoriesList.get(i).getName());
}
// Creating adapter for spinner
ArrayAdapter<String> spinnerAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, lables);
// Drop down layout style - list view with radio button
spinnerAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
spinnerFood.setAdapter(spinnerAdapter);
}
/**
* Async task to get all food categories
* */
private class GetCategories extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Fetching food categories..");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(Void... arg0) {
ServiceHandler jsonParser = new ServiceHandler();
String json = jsonParser.makeServiceCall(URL_CATEGORIES, ServiceHandler.GET);
Log.e("Response: ", "> " + json);
if (json != null) {
try {
JSONObject jsonObj = new JSONObject(json);
if (jsonObj != null) {
JSONArray categories = jsonObj
.getJSONArray("categories");
for (int i = 0; i < categories.length(); i++) {
JSONObject catObj = (JSONObject) categories.get(i);
Category cat = new Category(catObj.getInt("id"),
catObj.getString("name"));
categoriesList.add(cat);
}
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("JSON Data", "Didn't receive any data from server!");
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (pDialog.isShowing())
pDialog.dismiss();
//populateSpinner();
}
}
/**
* Async task to create a new food category
* */
private class AddNewCategory extends AsyncTask<String, Void, Void> {
boolean isNewCategoryCreated = false;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Creating new category..");
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected Void doInBackground(String... arg) {
String newCategory = arg[0];
// Preparing post params
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("name", newCategory));
ServiceHandler serviceClient = new ServiceHandler();
String json = serviceClient.makeServiceCall(URL_NEW_CATEGORY,
ServiceHandler.POST, params);
Log.d("Create Response: ", "> " + json);
if (json != null) {
try {
JSONObject jsonObj = new JSONObject(json);
boolean error = jsonObj.getBoolean("error");
// checking for error node in json
if (!error) {
// new category created successfully
isNewCategoryCreated = true;
} else {
Log.e("Create Category Error: ", "> " + jsonObj.getString("message"));
}
} catch (JSONException e) {
e.printStackTrace();
}
} else {
Log.e("JSON Data", "Didn't receive any data from server!");
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
if (pDialog.isShowing())
pDialog.dismiss();
if (isNewCategoryCreated) {
runOnUiThread(new Runnable() {
@Override
public void run() {
// fetching all categories
new GetCategories().execute();
}
});
}
}
}
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
long id) {
Toast.makeText(
getApplicationContext(),
parent.getItemAtPosition(position).toString() + " Selected" ,
Toast.LENGTH_LONG).show();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
}
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="10dp" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New food category" />
<EditText android:id="@+id/txtCategory"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
<Button android:id="@+id/btnAddNewCategory"
android:text="Create"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="40dp"/>
<TextView android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Select food category"/>
<Spinner android:id="@+id/spinFood"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
OUTPUT :-
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