I am creating an application that does not store any data (other than basic user name, password, etc). It uses API calls to get data and displays them when loaded through Volley.
I know typically it is best practice to use content providers and loaders when you store things in SQLite. My question is: should I still be using content providers and loaders given that my app does not utilize a database. Does anyone have any best practices/tutorials on how to do so with Volley?
Thanks!
It depends on your use cases. But here, no there is no need. There are other callback mechanisms you can use like broadcasts, async tasks, handlers or even content observers. There is a nice official tutorial of how to communicate with the UIThread aka. the visible stuff from some background logic.
Also if you want to you also can use loaders without any content provider. See this so post for more informations.
Related
I can't seem to locate a built in mechanism to store user settings. I was hoping that electron provided a standard method for storing user settings across all desktop platforms. If there isn't a precedent for this I can implement it myself, I just didn't want to jump to a custom solution immediately. Research online is pretty sparse in this area. Thanks!
Each platform has different default locations for different kinds of data. So, if you want to store data in default locations based on platform, check out app.getPath(name)
It retrieves a path to a special directory or file associated with name.
You can also use it to differentiate between data the user wants to save, and data your application saves that you don't want to clutter up users directories.
Or if you just want to store files reletive to a specific path you can use the
app.setPath(name,path)
I've faced this particular problem with my Electron app and this post inspired me to write an NPM module called electron-json-storage.
This module allows to easily write/read JSON to/from app.getPath('userData'):
const storage = require('electron-json-storage');
// Write
storage.set('foobar', { foo: 'bar' }).then(function() {
// Read
storage.get('foobar').then(function(object) {
console.log(object.foo);
// will print "bar"
});
});
Electron doesn't give you anything out of the box for this. However, Electron does give you a method for getting the idiomatic location of storing user data in a cross platform way via the app.getPath API.
I'd say the 3 most common ways to do this are:
localStorage (or any HTML5 storage API)
flat JSON file (this is what I do, and I use electron-store for it)
embedded database like IndexedDB, neDB, or sqlite
Which one you choose will depend on your app's needs. If you only need to access this data in the renderer process, then I'd just use localStorage. Most of the time it seems you need to access the data in both the main and renderer, so a JSON file makes sense. If you're dealing with lots of data or complex querying, then maybe a database makes sense. I wrote about this more in detail here.
How about LocalStorage? If you need to access these settings from the browser process, you probably need to write your own (or just use a node.js library that implements this)
The best way that I have found is to store it in a simple file as JSON. The problem is that if you store that JSON in the app dir, then when you update the app, it will get wiped out. So you want to put it in the default directory for user settings for the current operating system. LUCKILY!!!!! There is a library for node developers that will help you find the userdata directory. The module is called appdirectory, and I have used it several times. It is extremely easy to use.
See APPDIRECTORY HERE
One could store data in cookies; Electron has a mechanism for it (https://electronjs.org/docs/api/cookies) and the cookies can be retrieved in the browser (Angular: https://docs.angularjs.org/api/ngCookies/service/$cookies, React/Other: https://github.com/reactivestack/cookies)
I was able to get it working with Angularjs.
I have a rails app that calls a third party API for weather.
The problem is that the API call is generally very slow and sometimes fails.
Showing the weather is not a necessity but it adds a nice bit of extra and pertinent information.
Right now I call the Wunderground API using Barometer gem in the controller which means the pages takes forever to load if the API is slow or fails.
I was hoping to move to this call to an AJAX call from the page once the page is loaded. I don't mind if the information shows but a bit delayed because as mentioned it is not hugely important.
I was just curious the best practices for making such a call? What is the Rails way?
The recommended way is to call to the API in the background (using a scheduler) and save the result in the database. Then in the controller you can get the data from the database and there won't be any delay.
I would say that you are quite correct in moving to an AJAX call from the browser- that way your page load is unaffected and it can take as long as it likes without your server having to wait on it. This is a classic case for loading the data asynchronously ( through callbacks and/or jQuery's deferredapproach ) so that everything else is available while the data loads and your users aren't waiting on some information that they might not be very interested in to start with.
In terms of keeping it Rails, your main consideration is whether you can and/or want to make the call directly from the browser to the service, or whether you want to proxy it through your application to some degree, which would save on potential cross-domain request problems. Again this is very much your decision and will depend on whether you have any API keys you need to transmit with requests and so on, but if the request can run directly from the user to the weather API then that would allow you to cut out the intermediate step on your part.
I would like to sync a core data app with a user with a different iCloud ID and I am trying to figure out the most graceful way to do this. I do not want the data to sync with all users, but want to be able to sync among family members for instance. From the research I have done, I do not think I can do that using iCloud Core Data sync because it only syncs between devices with the same iCloud ID. I have looked at this stackoverflow answer and read a little bit about Ensembles, Parcelkit and TICoreDataSync, Parse etc., but it is not clear to me if any of those options will allow me to sync with multiple users. Does anyone have a good method for syncing a Core Data app with multiple users?
Ensembles and TiCoreDataSync might work. They can use Dropbox file syncing, so in principle they should work with Dropbox shared folders. I don't think these are the main intended uses, so I suggest contacting the developers and/or doing some good testing yourself before assuming this would actually work.
You'll need to think about the user experience, though. At a minimum, your users would both need Dropbox accounts and would have to set up a shared folder before beginning to sync data this way.
Parcelkit probably won't work. It uses Dropbox's data store API which, unlike other Dropbox services, doesn't appear to support shared data.
Services that do support this kind of sharing exist-- for example, Parse and Firebase-- but make sure to review their pricing carefully before using them. Also of course, there have been any number of projects that have their own custom server back end, but that obviously requires having someone on the team who can do that kind of work.
You need to think about other device types (Android at least) if you want your application to be reaching more users.
I'm doing the same now by the following way:
Setup an online database with proper web services (careful with implementation for security matters - DB should NEVER be exposed by anything other than the web services).
Create a Class for your communication with the server (using Class methods with security handling like authentication and authorisation).
Use the class in your app to communicate with the server (SQL operations are done on the server).
To integrate with CoreData you need to create the model in your app similar to the structure in the backend database. Then you need to create a similar class for the app that deals with only local CoreData.
A higher level class might be required if you want to make sure that operations done on both server and local data storage.
Besides, you have to implement a lot of conditions to make sure that data written in local ONLY after making sure that it is stored online (or create an engine for differed operations to run later).
Another Way if you are familiar with notifications:
Use structured notifications between devices for data operations in order to keep everything in sync with other users. The problem with this is the "Autonomy" of the operations. If two operations were done in approximately the same time, you have to find a way to make sure the order of the operations is done properly (maybe timestamp or something).
I'm looking into the same thing for my app and I 'think' you can do a fairly unsecured version of what you are after using using the public folder in cloud kit as mentioned in this question (no accepted answer at time of posting) : Private data sharing using CloudKit
You would need to find a way to differentiate between data that is truly public and those shared among the users you need and some level of authentication.
I'm going to try exporting a permission file with access permission in it to whomever I want to share with combined with a unique identifier located in that permission file.
Keep in mind, as mentioned in the comments of the linked answer, my implementation will be security by obscurity (thanks for that phrase) unless you find a way of adding proper validation to it but my data is relatively insensitive.
Hope this, or any ridicule in the comments, points you in the right direction : )
I need to share some sensitive data among activities.
I have two EditText which are basically username and password
I am consuming a webservice which on the base of provided username and password return some user info (DataType:String). Like userid,useremail etc.. which is basically in CSV format
I need these piece of information throughout my application.But i can't figure out which is the better way.
-- One way i could found out so far is to use sqlite with MonoAndroid
-- Other way i found out is using Application class
I just started to learn android today , but i want to know if there are some other ways to share data ?
As you mentioned, a global Application class and the database are two good ways to share application-wide data. One thing to be careful with is that your Application class could be recycled when the app is in the background, so you would lose any data that hasn't been persisted to something more permanent.
In addition to the database, you can also persist data down to the filesystem as well. This recipe from Xamarin has an example of writing directly to a file. Most of the classes you'll need to do file access are found in the System.IO namespace. Mono for Android also supports isolated storage, which provides a higher level API for reading and writing files.
If you simply need to pass data directly between activities, you can do so by adding it as an extra to the intent. This recipe explains how to do that.
If you want to wrap up access to a particular resource in a more managed fashion that can be accessed by either other parts of your application or even external applications, you can look into implementing a content provider. Android itself provides several built-in content providers for resources like contacts and media, if you need an example of what it's like to use one. This recipe explains how to read from the contacts provider.
i've used contentproviders with DB.it has some data in it.i need to make those data available to all other applications.How? Usually the main use of content provider is to store and retrieve data and make it accessible to all applications. They’re the only way to share data across applications; there’s no common storage area that all Android packages can access.I used the code from below link..
http://ashwinrayaprolu.wordpress.com/2011/03/16/custom-content-provider-in-android/
Distribute your Content URI and define your API.
Provide the string of your Content Authority and the paths you recognize. Explain to your users how the tables in your DB map to your paths. Document what the columns in your tables are. Users with your content URI can read and write your databases using standard calls to ContentResolver and the insert/delete/update/query calls.
Provide access control in your <provider> tag in your AndroidManifest.xml. Look at The documentation especially with regard to android:exported, android:grantUriPermissions, android:permission, android:readPermission and android:writePermission. You'll need to decide how to use those based on your use cases. Also, the <grant-uri-permission> tag will give you even more fine-grained control.
Write other apps to use those calls you just documented and allowed permissions for.