I'm trying to write the most basic application for windows phone 7 and want to be able to send files (specifically XML in case that changes anything) to my app. Currently I have a WCF service setup so I can send push notifications through it. The problem is that there is a limit on the amount of raw data I can send via a push notification.
My solution to this is to send the initial push notification (either tile or raw) to alert my application that I want to send a file to it and then make the app somehow communicate with a server (everything is on my personal computer btw - I'm just trying to figure out how things work) - from which the app will recieve/download the files.
What is the easiest way to accomplish this? Note that I'm not concerned with security or anything like that.
Clarification - the question is essentialy: how do I transfer files from/to a server to/from the phone? Assume everything else was handled - the app is up and running and the user has given or will give permissions to every possible thing he may give his permission to.
Unfortunately, the total size of a push notification (including HTTP headers) is 1kb. This means that it can't be used to send large amounts of data.
Instead of sending the whole file, send a notification (raw or toast—as appropriate) which should be treated by the application as a trigger to go and retrieve the new file/data/whatever from the server. It may also be worth checking for new messages when your app starts. However, if when you start the app it will notify the server that it is ready to receive raw notifications and such messages will be sent indicating new content is available, it may be unnecessary to add this extra check.
To transfer files to/from the phone you will need to use either HttpWebRequest or WebClient as this is the only way to use HTTP on the device and HTTP is the only protocol currently available to transfer data.
While WebClient may appear to be easier to use than HttpWebRequest it is less flexible and will automatically perform it's callback on the UI thread and if you're downloading files in the background you almost certainly don't want this.
There is no way to transfer files to/from a conencted PC and have them exclusively available to your app.
First of all: you won't be able to do this approach automatically - the user will have to open your app to do that because WP7 SDK doesn't allow your app to run on background/start automatically once a push notification is received.
The only way to communicate with your server, at this point in time, is web services. If I were you, I would check for new information available once the app is started, if there is new info, I would call one or more web services which would return me all the information that I need.
If you want, you can use a timer to check for information periodically.
As I said, it will only work while your app is running (check the app lifecycle if you don't know it yet), WP7 doesn't allow apps to run in background, that is a serious limitation IMHO.
Good Luck,
Oscar
Maybe a little bit off topic but when I was thinking about file sharing in my WP7 app, I found two approaches:
Integrate an app with Dropbox
Use advanced explorer for WP7
You can use the WebClient class and the DownloadStringAsync method in order to download data from a web service .
A good example of this is Scott Guthrie's Twitter app from MIX10 .
George
Related
I wonder to know which technique and tools I should use to have the ability to send real time notifications to users. Specifically if I build a messaging system.
I can see that modern social networks can send notifications about new messages almost immediately. Even when the user 'A' from one country writes a message to the user 'B' in another country you can see that the user 'A' writes a message and you immediately see it (even if those users live in different continents).
I tried to figure out how it is possible and find any information about this but without success.
The only thing I found out is the technique when we use a Redis or RabbitMQ server with several servers which acts like publishers and subscribers. Our API servers receive new messages then they push a new message in the queue then subscribers receives the messages and if they have an open WebSocket with the recipient they push this message in the WebSocket and a client receives the message.
But it really won't work if you have a distributed project and your clients are connected to the nearest servers in the nearest data center.
The question is: what technologies/techniques/anything we should use to be able to build notifications in a distributed project?
If you develop your distributed app/system using web technologies, you can consider building what is referred to as a Progressive Web App. With PWAs you can add push notifications in a relatively easy way. You could start with a PWA approach, and then decide later on if developing a native app as well (i.e. iOS or Android) would be necessary.
There are many resources to learn and guide you in developing progressive web apps. Check the references I mentioned above, and you can do this codelab as a starting point.
I am working on a product for Windows 8 that needs to perform some low-level tasks, display some UI, and communicate with an external server. I definitely need a Windows service to accomplish the low-level tasks. At the same time, I would like to use the cool features of Windows App Store apps, like push notifications, live tiles etc... for the UI. In this design, both my service and my app would communicate with my external server.
The flow would be something like: my Windows service sends some information to my server, which then sends a push notification to my App Store app.
I understand that deployment is not pretty in this scenario, but let's put that aside for now. My problem: How does the server know that the service and the app are on the same machine, and consequently linked together? i.e. When my Windows service sends information to the server, how does the server know where to send the push notification? I need is some sort of shared, unique, identifying information.
I have seen lots of discussion (usually frustrated in nature) about the lack of inter-process communication between App Store apps and desktop apps. In my case, I have two options:
Generate the exact same unique identifier in the service and in the app. This seems unlikely because apps don't seem to be able to access very much system-specific information. I'd love to be shown that I am wrong about this.
Generate a unique identifier in the server OR in the app and communicate it to the other component. Potential ways to do this:
Create the identifier in the app, save it to a file, and then access the file from the service.
Some sort of local socket solution (I've read this doesn't work, but have not tried)
Of course, option 2 seems likely to violate the Windows 8 app Certification Requirements, notably:
Windows Store apps must not communicate with local desktop
applications or services via local mechanisms, including via files and
registry keys.
Any advice would be most appreciated.
I'm not a lawyer, but if it says "via local mechanisms" then you could still possibly communicate via a cloud service as long as having both apps installed isn't necessary to have some features in the app or if you don't mean to publish the app in the store.
You could save some sort of a token in the documents folder or if your desktop app can run with appropriate permissions - it could access the local data folder of the Windows Store app to synchronize the token for use in communication with the web service.
Perhaps the user could just be asked to copy and paste a token between the two apps?
Just wondered if it was possible to send a toast from one WP7 phone to another.
Example of use:
User A presses a button on their phone to alert other users driving nearby with status "empty" that they are needed at the GPS location of User A
If anyone can provide some insight on if this is possible, and how it can be done, it would be great.
Thanks,
Can you?
No.
If I understand your question correctly, no it is not possible.
I understand your question to be "can I do this without having to implement something on a server somewhere?" And the answer to that is unfortunately "no".
What you will need to do as #softarn and #MrMDavidson alude to, you will need to implement something on the server.
But why not?
The reason for this is pretty simple. IF it was possible to do this, then it would open the door for abuse. Imagine if, without having to go through a Microsoft server, I could write a bit of code that would send push notifications constantly to all my users (who had downloaded my app of course). What happens if my users are on data plans that charge per bit? Well I've just screwed over a whole bunch of my users, and not only are they upset with me, they're upset with their stupid phone. Alternatively, what if Microsoft wants to give all windows phone users the option to get push notifications only every 15 minutes instead of immediately? Well, without operating as a go-between, Microsoft would be entirely unable to provide such functionality.
Here's how to fake it
So, in order to interact with toast notifications, it's a requirement that Microsoft gets to play middle man, so if needed, they can pull the plug on / monitor / regulate toast notifications on behalf of the user.
If you wanted to implement a bit of server code that emulated this behavior, that is certainly possible. As #MrMDavidson says, you'd basically need to take the following steps in the architecture of your app:
User's GPS location changes
WP7 app contacts a server that you own, notifying it that the user has moved
Your server code makes note of this, storing the data in a SQL database
After storing your new location, the server scans the SQL database for all other users of your app who are "nearby" and have their status set as "empty"
For each of the users in the database that match the criteria of being (a) nearby, and (b) having an empty status, the server code calls the user's "channel uri", sending the desired message
To your users, it's all the same
This would effectively accomplish your goal, and from the perspective of users, the experience would be seemless, and for all intents and purposes it will appear as if they got a notification directly from another user's phone.
Hope that clarifies things, I did assume you're familiar with the general workflow of sending Toast Notifications.
Happy coding!
Provided that User A's phone knows the push notification URI for User B's phone then, yes, you can send notifications from one phone to the other. However the question becomes; How do you distribute User B's notification URI to User A's phone? You'll either need an "offline" mechanism (email, for instance) or a server to act as a central repository. You're probably better off having a service layer over the top of the push notifications though to manage user-to-user relationships. Then User A's phone can say "Tell my friends that they're needed!". This can be an async-fire-and-forget call to your server. Your server can then implement retries and parallel execution to notify all User A's friends that they're needed at the location.
Yes of course it is possible. Read on to how push notifications work, though I don't think it will be as easy as you think. You'll need (I think) a server that the phones communicate through.
I am working as part of a team using Android and WP7 to create apps that communicate with a server. So ideally we want a consistent approach to receiving the data from the server.
I currently am using HTTPWebRequest to form a SOAP message and send it to a Java-based web service to receive messages (Adding as a ServiceReference didn't work no matter what I tried) At the moment it's a simple case of receiving the full list of things and just recreate the list each time via DespatchTimer to do periodic calls. But of course periodic pollin is likely to be ratehr battery intensive so not the best apporach for my needs.
I now need to change the code so that changes are pushed rather than polled. The team is looking at XMPP to do this as Android libraries are readily available to do this but I am having trouble finding open source libraries to do this.
Microsoft Push seems available but this appears to require a Microsoft based server side environment to push unless I have misinterpreted this? Or even if push notifications are a sensible way to do this.
So what I would like to know is the approach to handling pushed messages in this scenario which i hope someone out there has had experience in
Thanks
Microsoft Push Notification System [MPNS] does not require a MSFT-based server backend. It simply relays the Push Notifications through carrier or other data channels to subscribing phones. You should be able to make HTTP POST requests to MPNS at the Windows Phone subscriber Channel URI & MPNS would deliver the Push Notifications for you. Your server side can be anything, as long as you able to make the HTTP requests.
A good starting point can be found here.
Hope this helps!
I want to develop an application that works by receiving text messages from users to gather data. I have no clue where to begin and what to begin with. I can code in Python, C++, PHP and can do Java also.
I was wondering if there can be a personal development setup or framework on which I can develop such application. Releasing it is a different story but I do not have any idea about what setup is needed to develop this application.
Also, how much would this setup cost? Are there open-source or any other cheap alternatives?
There are a lot of services out there that let you receive SMS via a web request. The one I work for Twilio will send you a simple POST request to a URL of your choice containing To, From and Body whenever you receive an incoming message. You can read more about how it works here.
This service offers an api for receiving text messages. You can use the shared number and send it to your server with a keyword or you can pay a monthy fee to have your own dedicated number. So there would be a good place to start.