I'm trying to create android application in which user will be receiving notification every hour with some short string info on his choice, like some random word from urban dictionary, or some random grammar rule. But the problem is I cant find any tips about how to get that random info and parse it into my app. For example urban dictionary have api only for getting results by Word query. Maybe there is any sites with useful info that have api which will be easier to use in my app or maybe i should use any other solutions?
You can scrape the website. Use below code to get the website in html format and scrape it using JSoup
DefaultHttpClient client = new DefaultHttpClient();
HttpGet get = new HttpGet("http://www.urbandictionary.com");
ResponseHandler<String> handler = new BasicResponseHandler();
String response = httpClient.execute(httpGet, resHandler);
// response has the website in html format
But make sure you contact the website and let them know you are doing it. I am not sure about the legality behind it.
Related
I am building an android app with the following code:
try{
HttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost("http://10.0.2.2/tut.php");
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
}catch(Exception e){
System.out.println("Exception 1 caugt");
}
This apps works fine in my computer.
I want everyone download this app can use it and read the data from phpmyadmin.
can any one teach my how to do this?
(I want the data in phpmyadmin can be read from public user.)
And do I need to change the code?
HttpPost httpPost = new HttpPost("http://XXXXXXXXX/tut.php");
To make your app available to everyone you have to host your data online. There are many ways you can achieve this and it depends a lot on what type of application you intend to distribute.
If you just want to start trying out how things work you can buy a normal web hosting which supports mysql and php. This will cost you between 30 to 60 euros for a year. You setup your database, upload your php api and your good to go.
If you want a more professional approach you can choose to host in the cloud via cloud services the like of Amazon Web Services and Microsoft's Azure. This has a big learning curve but it gives you total control over the server and also huge experience.
As of now, if I have to store something from Android to the server, I make an HTTP request of a GET URL, with data in the form of parameter values. On the server side, I use PHP to extract the parameter values and store them in database.
Similarly, if I want to get something from the server to Android, I post a JSON string on the webpage using PHP. Then I read it in Android using HTTP request, convert the string to JSON and then use the data.
This method of PHP-MySQL-Android-JSON is very easy but not secure. Suppose I want to store the score of player from my game in Android to the server's database, it is easy to execute some URL like www.example.com/save_score.php?player_id=123&score=999 from Android. But anyone can update his score if he comes to know the php file name and names of parameters, by simply typing this URL in a browser.
So what is the correct method of interacting with a server (my server supports PHP but not Java)?
I have heard about RESTful and KSOAP2, but know nothing about them. Can you please explain them a bit in lay man language (reading the proper definitions didn't help me)? What are these used for?
What is the best way to send score to the server? Any tutorial link would be great.
Thanks.
Edit 1:
I don't use proguard to obfuscate my code for several reasons. So anyone can reverse engineer the apk, look into the code, find the URL to update the score, write his own POST method and update his score. How can I stop this from happening?
Use POST method to post data from android and get it in php. e.g. use this method to send your data in json formate , which will not be showing in url.
public static String sendRequest(String value, String urlString) {
try {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(urlString);
httppost.setHeader( "Content-Type", "application/json");
//value = "";
StringEntity stringEntity = new StringEntity(value);
stringEntity.setContentEncoding("UTF-8");
stringEntity.setContentType("application/json");
httpclient.getParams().setParameter(CoreProtocolPNames.USER_AGENT, System.getProperty("http.agent"));
httppost.setEntity(stringEntity);
HttpResponse response = httpclient.execute(httppost);
String responseString = convertStreamToString(response.getEntity().getContent());
return responseString;
} catch (Exception e) {
Log.d("check", ""+e.getMessage());
return ERROR_SERVICE_NOT_RESPONDE;
}
}
And call this method like this.
sendRequest({"player_id":1,"score":123}, "www.example.com/save_score.php");
And get json body in php and parse it.
I think you should read more documents about RESTful, Http POST and GET before starting. Your example url is GET method. It should be used for getting public information or query data. If you want to change something in server side, you should use POST method, it is more security than GET.
My recommend is using RESTful because it is painless than SOAP, especially for Android. Here is an example HTTP POST on Android.
I'm writing an Android app that should get data from a certain web application. That web app is based on Servlets and JSP, and it's not mine; it's a public library's service. What is the most elegant way of getting this data?
I tried writing my own Servlet to handle requests and responses, but I can't get it to work. Servlet forwarding cannot be done, due to different contexts, and redirection doesn't work either, since it's a POST method... I mean, sure, I can write my own form that access the library's servlet easily enough, but the result is a jsp page.. Can I turn that page into a string or something? Somehow I don't think I can.. I'm stuck.
Can I do this in some other way? With php or whatever? Or maybe get that jsp page on my web server, and then somehow extract data from it (with jQuery maybe?) and send it to Android? I really don't want to display that jsp page in a browser to my users, I would like to take that data and create my own objects with it..
Just send a HTTP request programmatically. You can use Android's builtin HttpClient API for this. Or, a bit more low level, the Java's java.net.URLConnection (see also Using java.net.URLConnection to fire and handle HTTP requests). Both are capable of sending GET/POST requests and retrieving the response back as an InputStream, byte[] or String.
At most simplest, you can perform a GET as follows:
InputStream responseBody = new URL("http://example.com").openStream();
// ...
A POST is easier to be performed with HttpClient:
List<NameValuePair> params = new ArrayList<NameValuePair>(2);
params.add(new BasicNameValuePair("name1", "value1"));
params.add(new BasicNameValuePair("name2", "value2"));
HttpPost post = new HttpPost("http://example.com");
post.setEntity(new UrlEncodedFormEntity(params));
HttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(post);
InputStream responseBody = response.getEntity().getContent();
// ...
If you need to parse the response as HTML (I'd however wonder if that "public library service" (is it really public?) doesn't really offer XML or JSON services which are way much easier to parse), Jsoup may be a life saver as to traversing and manipulating HTML the jQuery way. It also supports sending POST requests by the way, only not as fine grained as with HttpClient.
I am trying to log into a site and load a webpage programatically in android. Meaning, I have the password and login and need to submit a webform and get the response page. I tried the code here: Doing HTTP Post with Android
but I think I may be doing it wrong.
If this is the site I'm trying to access: http://goo.gl/eiBhP
and my code is
HttpClient httpclient = new DefaultHttpClient(httpParameters);
HttpPost httppost = new HttpPost(Constants.MAIN_URL);
List<namevaluepair> nameValuePairs = new ArrayList<namevaluepair>(2);
nameValuePairs.add(new BasicNameValuePair("username", "correctusername"));
nameValuePairs.add(new BasicNameValuePair("password", "correctpassword"));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpClient.execute(httpost);
Then I should be able to use
BufferedReader br = new BufferedReader(new InputStreamReader(
entity.getContent()), 8096);
to get the response. The id of the login and pass on the site ate username and password. should I also somehow submit the button as a name value pair? I cant seem to get this to work, it just returns the login page. Please Help. I've tried reading over the other similar questions but I can't seem to get it to work.
Basically, you need to make sure that your code is submitting exactly the same information as the webpage.
As Selvin points out, there's a good chance that the website is using some form of tracking - be it in hidden input values, cookies or some other state-based data.
You need to look at the source of the login webpage and understand what it is doing when you submit login details - you don't necessarily need to know what all the values mean, but your code must submit the same POST data.
If the website is using state information, you won't be able to hard-code those input values in your code. You'll probably need to retrieve a new instance of the login webpage each time using a HTTP GET request and then parse the data to extract the relevant state data. Don't forget that they may also be using cookies which you may need to submit.
All in all, you probably need to do a lot more work to get it to a working state. Not trying to dissuade you (and I don't know what you're trying to achieve), but perhaps it's easier just to use the website!
I need to create an Android application, I'm not sure which is a better way of doing this by better I mean should I use the WebView or create an application .
I need to implement the existing application which is a ASP.NET application which mainly consists of a login screen, once the user logs in he will see a list a items in probably a gridview based on the selection from the gridview. He then will be shown more detailed info about the selected item.
The above is a web application I need to implement this as a app on Android phone.
Also there will be a need to use the GPS where based on the GPS values the department will be selected and also use the camera to take a picture and save it on to the server .
A solution which I was thinking of was to expose .NET web services and then access it in the android phone!
But I am very new to Android development and really do not how to go about this. Is there any better solution?
Can anyone help me as to how do I go about this ?
Pros:
Android App may work faster then web applications (but still depends on web page complexity)
By the help of this community and android developer site you can complete your app within a 2-3 weeks.
As you stated picture capture/upload and GPS etc are advantages of the smart phone app.
Cons:
Later, you may need iPhone, Blackberry apps!
Instead of .Net web service which typically returns XML, you can go for HTTP call with JSON response (I've seen it in Asp.net MVC). So that you can easily parse the data on android app.
Added:
HTTP call:
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpGet httpGet = new HttpGet(getString(R.string.WebServiceURL) + "/cfc/iphonewebservice.cfc?returnformat=json&method=validateUserLogin&username=" + URLEncoder.encode(sUserName) + "&password=" + URLEncoder.encode(sPassword,"UTF-8"));
HttpResponse response = httpClient.execute(httpGet, localContext);
BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
String sResponse = reader.readLine();
JSONObject JResponse = new JSONObject(sResponse);
String sMessage = JResponse.getString("MESSAGE");
int success = JResponse.getInt("SUCCESS")
There are two approaches available to you:
Build an Android app.
Build a webapp, using W3C geolocation to access GPS coordinates. (see geo-location-javascript)
If you go for option (1), you'll want to expose your .NET service as a simple REST API (using JSON as Vikas suggested to make it just that bit simpler!)
Android already comes with all the components needed to access and parse such a REST API, specifically the Apache HTTP and JSON packages, and can be iterated on rather quickly once you have the basic request/parse framework in place.