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A Windows Phone Twitter Application : Part 2 of 2

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(Update : For trying out code posted on this blog post, Kindly use the official/ locked emulator . The unlocked emulator images have a known issue with HTTPS )

This is the second post in the series of posts explaining how you can build your own twitter application on Windows Phone 7

Post(s) in this series:

Part 1: Understanding oAuth

As explained in part one, the hard part of writing a twitter application is, to figure out/ understand the authentication/ authorization mechanism. Once You have done that, you can pretty much write an app for any service that has oauth as its authentication/authorization mechanism.

Now that we have obtained all the necessary authorization token(s), we can now access the protected resources on the user’s behalf.

How to Post a Tweet on a User’s behalf?

Using the access token and our app’s consumer secret , we need to make a POST request to twitter’s API to post a tweet from our app.

Using Hammock’s REST Library, You would do something like this :

if (txtBoxNewTweet.Text.Trim().Length == 0) { return; }
var credentials = new OAuthCredentials
{
      Type = OAuthType.ProtectedResource,
       SignatureMethod = OAuthSignatureMethod.HmacSha1,
       ParameterHandling = OAuthParameterHandling.HttpAuthorizationHeader,
       ConsumerKey = TwitterSettings.consumerKey,
       ConsumerSecret = TwitterSettings.consumerKeySecret,
       Token = this.accessToken,
       TokenSecret = this.accessTokenSecret,
       Version = "1.0"
};

var restClient = new RestClient
{
        Authority = TwitterSettings.StatusUpdateUrl,
        HasElevatedPermissions = true,
        Credentials = credentials,
        Method = WebMethod.Post
};

restClient.AddHeader("Content-Type", "application/x-www-form-urlencoded");

// Create a Rest Request and fire it
var restRequest = new RestRequest
{
       Path = "1/statuses/update.xml?status=" + txtBoxNewTweet.Text
};

var ByteData = Encoding.UTF8.GetBytes(txtBoxNewTweet.Text);
restRequest.AddPostContent(ByteData);
restClient.BeginRequest(restRequest, new RestCallback(PostTweetRequestCallback));

Now that you are able to make posts, you need a way to see the posts you have made on the user’s twitter account!

Well For looking at status updates, you don’t need authorization. You can directly give a call to the twitter api and you will get your status updates. ( This sample code is as demonstrated on Scott Gu’s blog )

 private void GetUserTimeLine()
        {
            WebClient wcTwitterTimeline = new WebClient();
            wcTwitterTimeline.DownloadStringCompleted += new DownloadStringCompletedEventHandler(wcTwitterTimeline_DownloadStringCompleted);
            wcTwitterTimeline.DownloadStringAsync(new System.Uri("http://api.twitter.com/1/statuses/public_timeline.xml?screen_name=" + userScreenName));
        }

        void wcTwitterTimeline_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e)
        {
            if (e.Error != null)
            { return; }
            XElement Tweets = XElement.Parse(e.Result);
            listboxMyTimeline.ItemsSource = from tweet in Tweets.Descendants("status")
                                            select new TwitterItem
                                            {
                                                UserName = tweet.Element("user").Element("screen_name").Value,
                                                Tweet = tweet.Element("text").Value,
                                                ImageSource = tweet.Element("user").Element("profile_image_url").Value
                                            };
            Dispatcher.BeginInvoke(() =>
            {
                listboxMyTimeline.Visibility = Visibility.Visible;
                txtBoxNewTweet.Visibility = Visibility.Visible;
                btnPostTweet.Visibility = Visibility.Visible;
            });
        }

With this, you are pretty much able to make a basic twitter app, that allows you to post tweets.

Using the Twitter api (Found here) You can create a full fledged twitter app.

As promised, I am uploading the source code for the app. You can download the source here.

(UPDATE : I have updated the code snippet, so that the app now runs on the public beta of the tools , Thanks Don for pointing this out )

Once again, Thanks for your support. With the final SDK Bits coming out this September 16th and with WP7 hitting the RTM status (Congratulations to the Windows Phone team @MSFT, Will be  queuing up the store when, it hits retail Smile), The next couple of weeks seem to be really really interesting.  Stay tuned for more exciting WP7 stuff

Written by sudheerkovalam

September 5, 2010 at 2:12 pm

A Windows Phone 7 Twitter Application : Part 1 of 2 (Understanding oAuth)

with 59 comments

(Update : For trying out code posted on this blog post, Kindly use the official/ locked emulator . The unlocked emulator images have a known issue with HTTPS )

As Promised in the previous post(I Know it was very long ago), We will try to build a Twitter application. Building a twitter app is a very easy task, and this post intends to guide you Step by step in creating your first twitter application. This post will speak about getting the app authenticated/authorized using the oAuth Mechanism.
The target platform is Windows Phone 7  in  this post, but you can pretty much a build a twitter app on any other platform based on this tutorial
Step 1: Register Your Twitter app on dev.twitter.com
Twitter needs to know that You are writing an app which accesses/posts tweets on your behalf. You tell this to twitter by registering your app on twitter.
image
twitterAppRegistration
When Registering your app, ensure that You set the Application type to browser and specify a call-back URL. (Twitter has certain requirements on Call-back URLs, i.e. it will not accept non HTTP URLs ( You need to ask twitter specially for  that ). For Demo purposes, i have specified Google.com as my default call-back URL.You can specify your custom page hosted on your domain, if you want to
This is how your app settings on twitter would look like:
AppSettings
Make a note of the highlighted URLs and your consumer key and secret.( Wondering what these are? Continue Reading or Read about oauth here)
Now comes the fun part, As usual fire up Visual studio 2010. Do a File | New Project. Select a Windows Phone Application from Silverlight for Windows Phone Section.
Twitter exposes a RESTful Service to access a user’s tweets etc. Twitter as of now only allows oAuth and XAuth as the only authorization mechanism. Since we have to have to consume a REST service along with oAuth, we will be  using a REST Client helper, that abstracts a lot of the hard work for me. (Such as adding the necessary headers, Computing oAuth Parameters such as Signature, Nonce, Timestamp etc. etc.)
For this demo, we’d be using the Hammock REST client available for download here. (Ohh BTW, Hammock is a very good example as to how same source code can target multiple platforms and multiple .net versions. Curious , about knowing how ? Go straight to the site and download the source code and have a look for yourselves.)
Now Lets get our hands dirty with some code for our first Twitter Application on Windows Phone 7 Smile
First Using the consumer Key and consumer key secret that you got by registering your application on twitter’s site, you need to request for a request token and request token secret
Request Token and request token secret are temporary set of credentials that let you acquire oauth access Tokens. The access token and access token secret are needed to access a user’s tweets.
To do this, I will use some neatly written helper classes in the Hammock library.( Else I would be actually writing code to do a lot of ugly stuff)

 var oauth = new OAuthWorkflow
{
     ConsumerKey = TwitterSettings.consumerKey,
     ConsumerSecret = TwitterSettings.consumerKeySecret,
     SignatureMethod = OAuthSignatureMethod.HmacSha1,
     ParameterHandling = OAuthParameterHandling.HttpAuthorizationHeader,
     RequestTokenUrl = TwitterSettings.RequestTokenUri,
     Version = TwitterSettings.oAuthVersion,
     CallbackUrl = TwitterSettings.CallbackUri
};

var info = oauth.BuildRequestTokenInfo(WebMethod.Get);
var objOAuthWebQuery = new OAuthWebQuery(info);
objOAuthWebQuery.HasElevatedPermissions = true;
objOAuthWebQuery.SilverlightUserAgentHeader = "Hammock";
objOAuthWebQuery.SilverlightMethodHeader = "GET";

What this helper class does is, hide a lot of stuff from the end user that needs to be done to acquire the request token and secret. Using the oauth WebQuery object all i have to do is to instantiate  a Hammock Rest Client object to fire a request to twitter’s servers.

 var requestTokenQuery = oAuthHelper.GetRequestTokenQuery();
 requestTokenQuery.RequestAsync(TwitterSettings.RequestTokenUri, null);
 requestTokenQuery.QueryResponse += new EventHandler(requestTokenQuery_QueryResponse);
In the response received event, I parse the response sent across by twitter. This should have the request token and request token secret in the response body.
var parameters = HelperMethods.GetQueryParameters(e.Response);
OAuthTokenKey = parameters["oauth_token"];
tokenSecret = parameters["oauth_token_secret"];
var authorizeUrl = TwitterSettings.AuthorizeUri+ "?oauth_token=" + OAuthTokenKey;

Now using the request token and secret, we need to get our app authorized to read/write data from the end user’s twitter account. To do this, we need to open a web browser and redirect the end user to twitter’s sign-in/ authorize page. To do this, I will be using a Web browser control and redirecting it to the authorize URL I have created above.

Dispatcher.BeginInvoke(() =>
{
      this.objAuthorizeBrowserControl.Navigate(new Uri(authorizeUrl));
});
The XAML for the browser control would look something like this:







The User sees the twitter page, where s/he signs in to twitter. Here, s/he is asked to authorize our twitter app.
twiiter_HomeScreentwitter_startScreentwitter_signIntwitter_signIn_2tiwtter_authorize
After you have authorized the application to access your data on your behalf, twitter will send the oauth request token (you received in the previous step) and a verification pin. Using these tokens, you can now request for the access token and access token secret. ( Arrgh!!! another set of tokens….)
Using the Hammock helper class that we used to get request tokens, we can acquire Access tokens as follows:
 var AuthorizeResult = HelperMethods.GetQueryParameters(e.Uri.ToString());
var VerifyPin = AuthorizeResult["oauth_verifier"];
this.objAuthorizeBrowserControl.Visibility = Visibility.Collapsed;

//We now have the Verification pin
//Using the request token and verification pin to request for Access tokens

var AccessTokenQuery = oAuthHelper.GetAccessTokenQuery(
                                             OAuthTokenKey,     //The request Token
                                             tokenSecret,       //The request Token Secret
                                             VerifyPin         // Verification Pin
                                          );

AccessTokenQuery.QueryResponse += new EventHandler(AccessTokenQuery_QueryResponse);
AccessTokenQuery.RequestAsync(TwitterSettings.AccessTokenUri, null);
In response twitter sends us the access tokens, the userID and the user’s screen name. I am going to store ‘em all, (Can prove to be very handy.)
var parameters = HelperMethods.GetQueryParameters(e.Response);
 accessToken = parameters["oauth_token"];
accessTokenSecret = parameters["oauth_token_secret"];
userID = parameters["user_id"];
userScreenName = parameters["screen_name"];

HelperMethods.SetKeyValue("AccessToken", accessToken);
HelperMethods.SetKeyValue("AccessTokenSecret", accessTokenSecret);
Dispatcher.BeginInvoke(() =>
{
    MenuItemSignIn.IsEnabled = false;
    MenuItemSignOut.IsEnabled = true;
    TweetButton.IsEnabled = true;
});
Phew!!! Now we are authenticated. We can now use the tokens we have received till now and the app can now access the user’s data(such as tweets, timeline etc.)

Written by sudheerkovalam

August 28, 2010 at 7:58 am

Windows Phone 7 : Launcher and Choosers : Part 2

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Let us continue our exploration of Windows Phone 7 Launchers and Choosers.

I had described Windows Phone 7 launchers here.

Chooser is an API , that launched a  built in functionality for the user to accomplish some task and returns back the data that was chosen by the user to the app.

We had seen how we could do a new launcher as and where needed, But in case of Choosers, the game is a little different.

A Chooser starts a different application ( Your app gets tombstoned)  and after the intended action is complete, ( Your app is back from the grave mwahahah!! ) the results are returned to your application. So we will have to declare the Chooser objects at a global scope within the PhoneApplicationPage class and  instantiate  it  in the page’s ctor and do the necessary plumbing (By that, i mean handling the necessary events etc.)

As of now following choosers are exposed

1. CameraCaptureTask:

The Camera Capture Task starts the camera of the phone. Now, the user is  actually seeing the phone’s camera app, where s/he can click  photos. Once the Photo is taken , we can save this photo in the Phone’s Media library. For doing this, we need to add a reference to XNA.Framework assembly.

using Microsoft.Xna.Framework.Media;
public partial class page2 : PhoneApplicationPage
{
   CameraCaptureTask cameraCaptureTask;

   // Constructor
   public page2()
   {
      InitializeComponent();
      // Initialize the CameraCaptureTask and assign the Completed handler in the page constructor.
      cameraCaptureTask = new CameraCaptureTask();
      cameraCaptureTask.Completed += new EventHandler<PhotoResult>(cameraCaptureTask_Completed);
   }

   private void btnCamera_Click(object sender, RoutedEventArgs e)
   {
      cameraCaptureTask.Show();
   }
   void objCameraCapture_Completed(object sender, PhotoResult e)
   {
       if (e.TaskResult == TaskResult.OK)
       {
          MediaLibrary library = new MediaLibrary();
          Random r = new Random(1234);
          Picture pic = library.SavePicture("SavedPicture_" + r.Next(11, 99).ToString() + ".jpg", e.ChosenPhoto);
       }
    }
}

ScreenShots:
Picture Capture Screen Accept or Retake the Pic


2. PhotoChooserTask:

As the Name suggests, the choosers shows you the WP7 picture library,from where you are allowed to pick a photo, in the completed event,
you receive a PhotoResult object that contains the Stream representation of the photo Chosen.
You Can do what you want to with the Photos’ File stream.
(Such as displaying it, uploading it to some service provider etc etc)

public partial class Page2 : PhoneApplicationPage
{
     PhotoChooserTask objPhotoChooser;
     public Page2()
     {
            InitializeComponent();
            objPhotoChooser = new PhotoChooserTask();
            objPhotoChooser.Completed += new EventHandler<PhotoResult>(objPhotoChooser_Completed);
     }
     private void btnChosePhoto_Click(object sender, RoutedEventArgs e)
        {            objPhotoChooser.Show();        }

     void objPhotoChooser_Completed(object sender, PhotoResult e)
        {
            if (e.TaskResult == TaskResult.OK)
                MessageBox.Show("Photo Selected");
        }
}

ScreenShots:

Media Library : Album ViewPhoto List shown in a pivot

3. SavePhoneNumberTask:

This Chooser, as  the name suggests, saves a phone number in the Phone’s contacts. This chooser does not return anything. The Completed event receives argument stating the status of the operation.

Note : You need to set the PhoneNumber property before you call the Choosers show() method. (Else your code might not work)

</span>
<pre>public partial class Page2 : PhoneApplicationPage
{
     SavePhoneNumberTask objSavePhoneNumber;
     public Page2()
     {
            InitializeComponent();
            objSavePhoneNumber = new SavePhoneNumberTask();
            objSavePhoneNumber.Completed += new EventHandler<TaskEventArgs>(objSavePhoneNumber_Completed);
     }
     private void btnSavePhoneNumber_Click(object sender, RoutedEventArgs e)
     {
            objSavePhoneNumber.PhoneNumber = "123-345-4567";
            objSavePhoneNumber.Show();
     }

     void objSavePhoneNumber_Completed(object sender, TaskEventArgs e)
     {
            if (e.TaskResult == TaskResult.OK)
            {
                MessageBox.Show("Phone Number Saved..");
            }
     }
}

Screenshots:
Saving a phone number for a existing contact Phone Number Type

4. PhoneNumberChooserTask

PhoneNumberChooserTask Allows you to pick a phone number from your contacts. If the contact has multiple phone numbers, you get to pick one of the phone numbers ( Isn’t that quite handy)

public partial class Page2 : PhoneApplicationPage
{
     PhoneNumberChooserTask objPhoneNumberChooser;
     public Page2()
     {
            InitializeComponent();
            objPhoneNumberChooser = new PhoneNumberChooserTask();
            objPhoneNumberChooser.Completed += new EventHandler<PhoneNumberResult>(objPhoneNumberChooser_Completed);
     }
     private void btnChoosePhoneNumber_Click(object sender, RoutedEventArgs e)
     {
            objPhoneNumberChooser.Show();
     }

     void objPhoneNumberChooser_Completed(object sender, PhoneNumberResult e)
     {
            if (e.TaskResult == TaskResult.OK)
            {
                MessageBox.Show("Selected :" + e.PhoneNumber);
            }
     }
}

Screenshots:

5. SaveEmailAddressTask

As the name suggests, this choosers saves an email to the contact list.

6. EmailAddressChooserTask

As the name suggests, this choosers shows you the contact list from where , you can chose a  contact and your app will receive the chosen contact’s default email address. Again, if multiple email addresses are available, the user is presented a choice of picking up an email address. This is sent back to your app.

Source Code for the sample Launcher and Chooser Demo,( whose screenshots are visible above )

Once Again, thanks for your support by reading this post. Keep watching this space for more on windows Phone 7.

Next Post : Building your twitter client for Windows Phone 7 with oAuth 🙂

Written by sudheerkovalam

August 14, 2010 at 9:01 am

Windows Phone 7 : Launchers and Choosers

with 5 comments

Windows Phone 7 seems to have captured my attention a lot these days. So I am ( and will be ) blogging about Windows Phone 7 like crazy. I believe that it is Microsoft’s first step in the right direction (in the phone OS business). So coming back to Windows phone 7 Platform. We all, by now know that all applications in Windows Phone 7 runs in its own sandbox (execution and file storage, both). And since, we  are developing apps for windows Phone 7, we will certainly need access to common, phone related functionality, say like sending an email, SMS etc. Recently, in Community Tech Days Pune, in the Windows Phone 7 app development session by Mayur Tendulkar, a very cool app was demoed for Windows Mobile 6.x. This app would send “happy new year” or “happy holidays” message to all the contacts in your phone. The idea was pretty cool. So for designing this app, we would need access to the phone’s contact list and then, will have to use the phone’s SMS API to send out Text messages. It is a different ball game here on Windows Phone 7 platform. Windows Phone 7 doesn’t give you access to native functionality directly, so Microsoft has exposed certain common functionality that you would want to use in your apps in the form of Launchers and Choosers.

A Launcher is an API, that launches built in functionality for the user to accomplish some task and returns nothing back to the calling function in  your app. API to make calls, Send SMS or Emails etc are an example of such APIs

A Chooser on the other hand is an API , that launched a  built in functionality for the user to accomplish some task and returns back the data that was chosen by the user to the app. API for Choosing contacts, photos etc. come under this category.

Important Note : Your application de-activates (i.e. gets tombstoned), when you trigger a launcher or a chooser. (Not sure what tombstoned means, read more about Windows Phone app life cycle here ). How to use Launchers in your application : Launchers are available in Microsoft.Phone.Tasks Namespace. Make sure to add a using statement for this namespace.

As of now Following Launchers have been exposed to us (Not exactly …):

1. EmailComposeTask :

As the name suggests, The EmailComposeTask lets you compose emails and send ‘em. You will off course need to setup an email account before you can actually use the email compose functionality. The good news, if no email account has been setup, the shell will ask you to setup an account. ( I guess in the final RTW SDK, this might actually trigger email setup, if not done already)


EmailComposeTask emailComposeTask = new EmailComposeTask();
emailComposeTask.To = "bill.gates@microsoft.com";
emailComposeTask.Body = "Windows Phone Rocks!!!"
emailComposeTask.Cc = "SteveBallmer@MSFT.com";
emailComposeTask.Subject = "Windows Phone";
emailComposeTask.Show();

2. PhoneCallTask:

Again, quite evident by the name itself. Phone call task will let you make a phone call.

PhoneCallTask phoneCallTask = new PhoneCallTask();
phoneCallTask.PhoneNumber = "180018001800";
phoneCallTask.DisplayName = "Steve Jobs";
phoneCallTask.Show();

Quite a wrong person to call, I know 😉

3. SMSComposeTask :

Lets you compose an SMS

SmsComposeTask smsComposeTask = new SmsComposeTask();
smsComposeTask.To = "1800-180-1800";
smsComposeTask.Body = "Cool Phone!!";
<pre>smsComposeTask.show();</pre>

4. SearchTask :

Lets you open the shell search engine

SearchTask searchTask = new SearchTask();
searchTask.SearchQuery = "Windows Phone 7";
searchTask.Show();

5. MediaPlayerLauncher:

Will Trigger the Phone’s Media Player Application

MediaPlayerLauncher mediaPlayerLauncher = new MediaPlayerLauncher();
mediaPlayerLauncher.Media = new Uri("vs_logo2010_WMV9_640x360.wmv", UriKind.Relative);
mediaPlayerLauncher.Show();

6. WebBrowserTask:

The WebBrowserTask will let you trigger the phone’s IE mobile browser and redirect the user to the page specified.

WebBrowserTask webBrowserTask = new WebBrowserTask();
webBrowserTask.URL = "http://developer.windowsphone.com";
webBrowserTask.show();

I was not able to find much detail on these Launchers. Folks reading this block can contribute.:

7.MarketplaceDetailTask:

From the Name of it seems, it will launch the phone’s Marketplace app and show details. Not used this one.

8. MarketplaceHubTask:

Launches the Marketplace Hub, i guess. I don’t think we will be able to test this on the locked emulator.

9. MarketplaceReviewTask

10. MarketplaceSearchTask

I will be posting the next post on using the Choosers and will also post the entire solution for your ready reference. Once again, thanks for your support and keep looking at this space for more Windows Phone 7 related posts.

Written by sudheerkovalam

August 6, 2010 at 3:02 am

Windows Phone 7 Process Life cycle

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What was made clear at Mix’10 was that third party apps in Windows Phone 7 wont be able to multi task. The reason provided was that too many apps running in the background may make the app in foreground run slowly. Once an user sees that s/he will definitely say that “Windows Phone 7 Sucks!, It is very slow and sluggish”.

Well what If we say that we will need multi tasking and will use it judiciously? well AFAIK, not Third party app multi tasking will be available in V1 ( Not sure , if MSFT intends to publish an OTA update to add multi tasking later )

With Windows phone 7, what MSFT promised was no  sluggish interfaces and apps that consume various data service and provide all the information you need in one place. And Frankly speaking off, they have done a decent job.

So, No Multi tasking, What does that mean for us developers?

Well in order to answer this question, we need to understand how an app will live on the phone ( the Windows Phone off course Open-mouthed smile )

When the app is Launched:

The app that you , me and many more developers will write will need to be launched from either the start experience or application list. When we do this, (from the programmer’s perspective) , a new instance of our application is created.  Well this does mean that we do get to write event handlers for events such as application launched etc..

However anywhere in the app, when the user presses the Start Button and/or triggers a Launcher or a chooser ( such as ‘”send an SMS” , “send an email”) etc, Your app’s state is saved and your app is put to sleep.

This process is called as “Tombstoning”

Wp7 App lifecycle

Following are the main events that we can use in our app to make our app feel as if it were really running in the background

1. Launching Event

When the app is launched, the Launching Event is fired. we can use this event, (usually an empty method pre written for you in app.xaml.cs) which we can use to instantiate stuff from the isolated storage. For e.g. , say you have an app that depends on some XML files that you need to read when the app launches, this is the event for you!, Write the code in the launching event

2. Closing Event

When the user clicks navigates through the app, a stack of page navigation is maintained. When the user hits the back button, the user is taken to previous screen.

Now when the user keep on hitting back button through the first page of the app. The app gets terminated and the closing event is fired. You can now write some app level data that you wish to persist, to the phone’s isolated storage.

3. Activated Event

Your app can be in the foreground or can be replaced with some app in foreground on some Launcher (such as send an email, call etc..). This is when the app is tombstoned and it also becomes possible that the app might not get activated again. The user can open many such apps,knocking off your app from the application stack ( the back button relies on the application stack to take you to a page in the current app or some page in previous app you had launched.) If the user were to launch the app from the start screen, it would create a new instance of the app

Now it is also possible that the user can reactivate your app by pressing the back button and coming to your app or even after the launcher completes. This is when your app is activated again. The Activated Event is fired when your app is activated after , say you complete a phone call when you were using the app . This is a good place where you can reload data you had stored in persistent store ( such as textbox data ,selected item etc . If you intend to store data entered in textboxes and you want to persist it )

4. Deactivated Event.

If an application is running and is subsequently replaced in the foreground by another application or experience, the first application will be deactivated. There are several ways in which this state can be invoked. An application will be deactivated if the user presses the Start button or if the device timeout causes the lock screen to be engaged. An application will also be deactivated when it invokes a Launcher or a Chooser, helper applications that allow the user to perform common tasks such as taking a picture or sending an email. In any of these cases, the running application will be deactivated and the Deactivated event is raised.

 

// Code to execute when the application is launching (e.g., from Start)

// This code will not execute when the application is reactivated

private void Application_Launching(object sender, LaunchingEventArgs e)
{
  //Get Data from Isolated Storage or a web service etc...
  System.Diagnostics.Debug.WriteLine("In Application_Launching event"+
     "... Nice Place to Initialize your app");
}

// Code to execute when the application is activated (brought to foreground)
// This code will not execute when the application is first launched
private void Application_Activated(object sender, ActivatedEventArgs e)
{
   System.Diagnostics.Debug.WriteLine("And We are back!!");
}

// Code to execute when the application is deactivated (sent to background)
// This code will not execute when the application is closing
private void Application_Deactivated(object sender, DeactivatedEventArgs e)
{
   System.Diagnostics.Debug.WriteLine("Go to sleep...zzz");
}

// Code to execute when the application is closing (eg, user hit Back)
// This code will not execute when the application is deactivated
private void Application_Closing(object sender, ClosingEventArgs e)
{
   System.Diagnostics.Debug.WriteLine("goodbye cruel world.");
}

 

Hope this blog post helps you understand the Windows Phone 7 app lifecycle.

I will try and cover many more details in further posts as and how I discover them Smile

Thanks for your support. I will be back with my next post in a few days

Written by sudheerkovalam

July 21, 2010 at 4:20 pm

My Experiences on Windows Phone 7 development : Part 1

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Wow. its been almost 6 months that I posted anything on my blog.

Anyways, I have been working on windows phone 7 for the past month or so.

This blog  post (of a series of blogs) will try and tell about my experiences of working on WP7.

First of all, We (As in our client, A Microsoft Partner Award 2010 winner) had an amazing demo at Worldwide Partner Conference. As you might have guessed, we worked on the demo and the actual product that will be unveiled soon.

I will put in my experience in much more details in days to come ( I will, I Promise!! )

Written by sudheerkovalam

July 14, 2010 at 2:02 am