#Override
protected Void doInBackground(Void... arg0) {
HttpClient httpClient = new DefaultHttpClient();
// Creating HTTP Post
HttpPost httpPost = new HttpPost("www.somewebsite.com");
httpPost.setHeader("Content-type", "application/json");
try {
httpPost.setEntity(new StringEntity(getJSONString(), "UTF-8"));
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
// Making HTTP Request
try {
HttpResponse response = httpClient.execute(httpPost);
System.out.println(response.getStatusLine().getStatusCode());
} catch (ClientProtocolException e) {
// writing exception to log
e.printStackTrace();
} catch (IOException e) {
// writing exception to log
e.printStackTrace();
}
}
This works fine for me. However I want to send other jsonobject with business data to server. How can I do that?
Just merge the 2 JSONObjects into 1.
{
"json_1": {
"a": "1"
},
"json_2": {
"b": "2"
}
}
YOu can only send one entity, so your function getJSONString() will need to be updated to return both objects as one string.
You might want to consider sending a proper JSON list.
[
{ /* object one */ },
{ /* object two */ }
]
I think this is much more preferable over a 'combined object'
{
"object one" : { /* object one */ },
"object two" : { /* object two */ }
}
Using a combined object makes it awkward to parse, as you have to explicitly get each sub object out of the main object. With the array, you can simply loop through each element of the list, which means adding more to the list is as easy as adding more to the list. Your exact usage may mean that the combined object is better, such as if you need to know the exact order the sub-objects should be handled; JSON lists are unordered you see.
Simple! Club both json's using a separator, and then delimit using the separator on the server.
Or build a new json object with both jsons' and send a common json object to the server.
Nithin
Related
I have 3 tabs in my app, each having its own Fragment. I need to populate each tab's Fragment with data that needs to be retrieved from my website's REST API.
To my understanding, the onCreate/onCreateView method in the Fragment class is where I should request the JSON data (how do I request it?).
Then I would loop through the data and insert it into separate lists or cards (how do I do this?).
Sorry for the beginner questions, but I'm not sure where to begin.
There are two ways to do this
1) through native android
private void makeGetRequest() {
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet("http://www.example.com");
// replace with your url
HttpResponse response;
try {
response = client.execute(request);
Log.d("Response of GET request", response.toString());
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
2) use third party libraries.Please refer this url https://github.com/square/retrofit
Example
https://github.com/square/retrofit/blob/master/samples/src/main/java/com/example/retrofit/SimpleService.java
This library will do all the things like GET,POST,Sync,Async and Error Handling.
you have to use AsyncTask When youre requesting anything from server, Asynctask runs in backgrouns so your UI thread will no be blocked by it.
Otherwise you can try using Volly library dosen't need an AsyncTask to work. It will work in background thread anyway '
It also provides you with sucess failure handlers(if youre into ajax and all it'll easier for you)
take a look at Volly Library
I have an application and I need to get some data from my database(MySQL and it stays on web, not local). I think a simple RestFul webservice will be the best option for me to access this database and get the data. However, I m not able to create the webservice. I did some researches but I got confused. All I need is just accessing the database and get a few data from the table. Please give me some help to create the neccessary webservice. I don't want it to be a complex webservice. Thank to you all
this is php page of web-service. in this userid is taken from android java file that requesting that data. and after that selecting data from mySql it will simply echo all data and that will be given to java file as response.
seluser_profile.php
<?php
//$con=mysql_connect("localhost","root","");
//mysql_select_db("android_db",$con);
$con=mysql_connect("localhost","root","");
mysql_select_db("android_db",$con);
$uname=$_POST['userid'];
$q="select * from user_details where username='$uname'";
$rec=mysql_query($q);
if(mysql_num_rows($rec)==1)
{
$arr=mysql_fetch_array($rec);
echo $arr[0]+" "+$arr[2]+" "+$arr[3];
}
else
{
echo "false";
}
?>
Java code for requesting to web service.
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://10.0.0.2/webservice/seluser_profile.php");
try {
// Add your data
//Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_LONG).show();
List<NameValuePair> namevpair = new ArrayList<NameValuePair>(2);
namevpair.add(new BasicNameValuePair("userid",valueIWantToSend));//in this first argument is name of post variable which we will use in php web service as name of post varible $_POST['fname'];
httppost.setEntity(new UrlEncodedFormEntity(namevpair));
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
str = inputStreamToString(response.getEntity().getContent()).toString();
//Toast.makeText(getApplicationContext(), "your answer="+str, Toast.LENGTH_LONG).show();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
use this java code in doInBackground method of Asynctask class. otherwise it will give you network handler exception.
private StringBuilder inputStreamToString(InputStream is) {
String line = "";
StringBuilder total = new StringBuilder();
// Wrap a BufferedReader around the InputStream
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
// Read response until the end
try {
while ((line = rd.readLine()) != null) {
total.append(line);
}
} catch (IOException e) {
e.printStackTrace();
}
// Return full string
return total;
}
and also add this function for string building from inputstream.
Here is a link, You may seen this while surfing, I know this is not an answer , but I cannot comment bcz I dnt have enough Rep.
http://www.androidhive.info/2014/01/how-to-create-rest-api-for-android-app-using-php-slim-and-mysql-day-12-2/
I used this in one of my project, customization was very easy..and a great tutorial.
I'm trying to setup a survey that my app users can take that will post the results to a rails app. The survey/questions/answers are built in the rails app, then displayed in the Android app. After the user answers each question it should post back to the server.
I suspect that it's something to do with my create method (the uncommented line works for creating a choice in the rails app but not for the Android post and the commented line appears to work for neither) but I'm relatively new to Android/Rails so any help would be much appreciated!
Here's my ChoicesController:
class ChoicesController < ApplicationController
# POST /choices
# POST /choices.json
def create
#question = Question.find(params[:question_id])
#choice = #question.choices.build(choice_params)
#choice.answer = Answer.find(params[:choice][:answer_id])
# #choice.answer = Answer.find(params[:answer_id])
respond_to do |format|
if #choice.save
format.html { redirect_to question_choices_path, notice: 'Choice was successfully created.' }
format.json { render action: 'show', status: :created, location: #choice }
else
format.html { render action: 'new' }
format.json { render json: #choice.errors, status: :unprocessable_entity }
end
end
end
My choice model:
class Choice < ActiveRecord::Base
belongs_to :question
belongs_to :answer
belongs_to :user
validates :question_id, presence: true
validates :answer_id, presence: true
end
Here's how I'm creating/posting my json in Android:
public boolean postChoice(String apiKey) {
boolean choicePosted = false;
try {
post();
} catch (Exception e) {
e.printStackTrace();
}
choicePosted = true;
return choicePosted;
}
public static void post() {
Map<String, String> choice = new HashMap<String, String>();
choice.put("question_id", "6");
choice.put("answer_id", "15");
String json = new GsonBuilder().create().toJson(choice, Map.class);
makeRequest("http://localhost:3000/choices/", json);
}
public static HttpResponse makeRequest(String uri, String json) {
try {
HttpPost httpPost = new HttpPost(uri);
httpPost.setEntity(new StringEntity(json));
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
return new DefaultHttpClient().execute(httpPost);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
Any help is much appreciated!
One big problem with your code is:
} catch (Exception e) {
e.printStackTrace();
}
You are swallowing all exceptions and my guess you are also swallowing the problem exception. You should look into logs what exception is recorded and also not use catch (Exception e) but instead have explicit exception.
Without actual exception it hard to diagnose, but my guess is that you are making this http request inside UI thread and Android framework explicitly forbids it (it makes your app non-responsive) and throws an exception.
Turns out the biggest problem I had was that I was not sending a CSRF token with my POST. including skip_before_action :verify_authenticity_token solved my problem. Since it's an API I have a few other security verification piece in place, but CSRF really only applies to web forms anyway.
Can anyone tell me which is the best, ease and flexible method to consume web service from android? I'm using eclipse.
Since you only care about consuming a webservice, I assume you already know how to send data from the web server. Do you use JSON or XML, or any other kind of data format?
I myself prefer JSON, especially for Android.
Your question still lacks some vital information.
I personally use apache-mime4j and httpmime-4.0.1 libraries for web services.
With these libraries I use the following code
public void get(String url) {
HttpResponse httpResponse = null;
InputStream _inStream = null;
HttpClient _client = null;
try {
_client = new DefaultHttpClient(_clientConnectionManager, _httpParams);
HttpGet get = new HttpGet(url);
httpResponse = _client.execute(get, _httpContext);
this.setResponseCode(httpResponse.getStatusLine().getStatusCode());
HttpEntity entity = httpResponse.getEntity();
if(entity != null) {
_inStream = entity.getContent();
this.setStringResponse(IOUtility.convertStreamToString(_inStream));
_inStream.close();
Log.i(TAG, getStringResponse());
}
} catch(ClientProtocolException e) {
e.printStackTrace();
} catch(IOException e) {
e.printStackTrace();
} finally {
try {
_inStream.close();
} catch (Exception ignore) {}
}
}
I make a request via _client.execute([method], [extra optional params])
The result from the request is put in a HttpResponse object.
From this object you can get the status code and the entity containing the result.
From the entity I take the content. The content would in my case be the actualy JSON string. You retrieve this as an InputStream, convert the stream to a string and do whatever you want with it.
For example
JSONArray result = new JSONArray(_webService.getStringResponse()); //getStringResponse is a custom getter/setter to retrieve the string converted from an inputstream in my WebService class.
Depending on how you build your JSON. mine is nested deeply with objects in the array etc.
But handling this is basic looping.
JSONObject objectInResult = result.getJSONObject(count);//count would be decided by a while or for loop for example.
You can extract data from the current JSON object in this case like:
objectInResult.getString("name"); //assume the json object has a key-value pair that has name as a key.
to parse "JSON" I recommend the following library is the faster and better.
Jackson Java JSON-processor
I've been searching the web for a way to do this for about a week now, and I just can't seem to figure it out.
I'm trying to implement an app that my college can use to allow users to log in to various services on the campus with ease. The way it works currently is they go to an online portal, select which service they want, fill in their user name and pwd, and click login. The form data is sent via post (it includes several hidden values as well as just the user name and pwd) to the corresponding login script which then signs them in and loads the service.
I've been trying to come at the problem in two ways. I first tried a WebView, but it doesn't seem to want to support all of the html that normally makes this form work. I get all of the elements I need, fields for user and pwd as well as a login button, but clicking the button doesn't do anything. I wondered if I needed to add an onclick handler for it, but I can't see how as the button is implemented in the html of the webview not using a separate android element.
The other possibility was using the xml widgets to create the form in a nice relative layout, which seems to load faster and looks better on the android screen. I used EditText fields for the input, a spinner widget for the service select, and the button widget for the login. I know how to make the onclick and item select handlers for the button and spinner, respectively, but I can't figure out how to send that data via POST in an intent that would then launch a browser. I can do an intent with the action url, but can't get the POST data to feed into it.
So here is what I have right now...
HttpParams params = new BasicHttpParams();
HttpClient client = new DefaultHttpClient(params);
HttpPost post = new HttpPost(action);
String endResult = null;
try
{
post.setEntity(new UrlEncodedFormEntity(myList));
}
catch (UnsupportedEncodingException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
try
{
String response = client.execute(post, new BasicResponseHandler());
endResult = response;
}
catch (ClientProtocolException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
So my question now... is how do I take the endResult screen, which should be the page returned after I logged in to my service, and display it in a browser?
What's wrong with them just using the built in browser? You can also submit a form using UrlEncodedFormEntity and HttpClient.
HttpParams params = new DefaultHttpParams(); // setup whatever params you what
HttpClient client = new DefaultHttpClient(params);
HttpPost post = new HttpPost("someurl");
post.setEntity(new UrlEncodedFormEntity()); // with list of key-value pairs
client.execute(post, new ResponseHandler(){}); // implement ResponseHandler to handle response correctly.
Okay and after you have the response in a string. The response since its a page is going to be in html. You need to use a WebView to show the html. WebView has a method loadData() that takes a string of html and displays it.
Based on #RobbyPonds answer, for the benefit of people wandering past here, below is a generic implementation to post and receive a response from a URI (NOTE Also contains waiting implementation to return a response, probably not every day implementation of network call):
private static String responseValue;
#SuppressWarnings({ "unchecked", "rawtypes" })
public static String sendPostToTargetAndWaitForResponse() throws ClientProtocolException, IOException {
final Thread currentThread = Thread.currentThread();
synchronized (currentThread) {
HttpParams params = new BasicHttpParams();
HttpClient client = new DefaultHttpClient(params);
HttpPost post = new HttpPost(HTTP_POST_URI);
// List Creation with post data for UrlEncodedFormEntity
ArrayList<NameValuePair> mList = new ArrayList<NameValuePair>();
mList.add(new NameValuePair() {
#Override
public String getValue() {
return getSampleJSON();
}
#Override
public String getName() {
return "json";
}
});
post.setEntity(new UrlEncodedFormEntity(mList)); // with list of key-value pairs
client.execute(post, new ResponseHandler(){
#Override
public Object handleResponse(HttpResponse response) throws ClientProtocolException, IOException {
responseValue = EntityUtils.toString(response.getEntity(), "UTF-8");
synchronized (currentThread) {
currentThread.notify();
}
return null;
}
});
try {
currentThread.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
return responseValue;
}
}