I want to create an app to estimate engineering costs: lots of tables, forms, a sidebar with a tree structure and so on. You can access a database in the cloud and create table structures according to records in the database.
Naturally that would be a website, however, if the user does not always have an access to the Internet, he/she can download a copy of that database (precisely, a copy of the current version of the database), so that it would be possible to get data from it and work locally. That is why an offline desktop app is needed.
Would it be possible to develop such a hybrid application without first creating a web app and then doing the same with a desktop app?
Previously i have looked into JavaFX, but we saw that it's too difficult to create a website out of that. Then we saw Electron, but i'm not sure if it is the right choice, because it seams that Electron is only used for desktop.
I'm lost as to why you feel you need a website/desktop hybrid. There are many APIs available to let you access a cloud database. All you have to do is find an API with web hooks, or APIs that specifically target the database type you are using (sql, mongo, or whatever). Then just cache a local copy once you've pulled down the database.
Work on the copy then push back to the database when they save, or try to do a push/pull every 5 minutes or something.
You can make a HTML page, which would:
Use AJAX calls if connected
Add relative <script> tag, thinking that HTML file lies in a folder on PC, and that script is somewhere nearbly.
In both cases, user will get same results.
Downloads are:
HTML file with inline script
JS file with database
or
zipped folder with HTML, database JS files and all scripts, images, css, etc. requred for HTML file to show properly.
Related
I'm trying to scrape off a user input from an application created with electron. I basically used the url to create the electron application in hopes to make an executable and use the following user inputs to tackle an issue with internet connectivity with the native application.
I have the source files for the original application but with me creating the electron application with just a url, i wouldn't have these files on the project. Is it possible for me to scrape user inputs without the original source files and just with basically an index.js in electron?
I Used various libraries and had a look around the html files by looking at developer mode etc, as well as trying to experiment by mixing with the source code, but didn't get any form of results that I needed.
I would like to write a js for an offline website (located on a local Windows server or any other server). It's supposed to look for files like PDFs in several directories and display them as search result on the "website", which isn't a real website, since it's on a local server and not in the web. The PDF is supposed to open in the browser after clicking it. I already have this kind of search engine as a php file, which I wrote with some help from friends. I also want to share this site with other friends. Basically I'll send them the whole folder with the html - document (or the .php site), so they can use it to search for certain pdfs in the folder. Its like a offline wiki for medical research documents. But I don't want them to always install php on their local servers, so they can run my php-searchmachine, thus I need to write it new as a javascript. By google and stack overflow I came across this solution https://www.codegrepper.com/code-examples/javascript/find+file+in+directory+javascript but it seems like that this needs node.js, so all have to install node.js, which is similar to installing php, I guess (im not familiar with node.js). Also I'm not sure if node.js is running on a normal client or server, which is not a webserver.
How can I start with such a project? Is javascript the correct attempt to solve this?
Windows Search has the ability to search PDF contents when boosted by a PDF (index) iFilter, this means the user can search and find instantly a new search word or a saved search it took only a second to hand enter this search (actually took longer to save for double click next time) just for illustration I chose a word I knew was in one file and actually found it is also in two other PDFs.
The problem for your JS coding is how to use JavaScript to interface with Windows Search since using explorer I could not run that search on a remote server shared library drive (I could see their contents as per second screen but for search, had to pull a local library copy down to my documents) and that is where your JS skills come into play. Personally I would avoid JS and use a VLC method to share view via a remote Lan server or simpler invoke a plain text indexed local copy of remote files for download as and when required.
I am working on a University project.
I have developed a test harness, one of the features of the test harness is visual regression testing.
I am developing a basic website, as a means to displays these generated images programmatically.
My original idea was to use a mongodb database, however after some reading many people advise not using mongodb to store images.
I then tried to use google drive and drop box, however they do not facilitate permanent url's to the stored images. Or in the case of dropbox, these urls are random so not programmatic.
I need to find a way to store these images, programmatically store them using a nodeJS script, programmatically access them using JS.
Any ideas?
You can use Amazon S3 for saving and retrieveing images with permanent url's
http://docs.aws.amazon.com/AmazonS3/latest/dev/Welcome.html
I'm developing a Chrome App to allow users to create virtual documents that are stored within the app itself, meaning I don't want the users to have direct access to the files.
The reason why this is is because when the app first starts, it's a screen showing previews/thumbnails of all the created files. If I gave users control over where the files were stored, this could be interferred with by having multiple files in various locations.
What I'd like to do is store everything inside of the app. If possible, I'd like to use JavaScript to create, modify, and edit files within the packaged app, not through the user-accessible file system. Is there any way to dynamically add files and folders to a packaged app using JavaScript?
If not, what are my options for a controlled system in which users cannot move their files to a different directory to keep my thumbnails/previews intact?
You only have read-only access to your package directory.
For an isolated virtual filesystem specific to your app, you should use the HTML5 Filesystem API. Yes, it has a big warning regarding its status, but it's the basis of Chrome's own APIs so it is not going anywhere in Chrome.
You should carefully consider though if it's really the best experience for your users. The good part though, if you ever wish to allow to use a location on the real filesystem, you don't need to change much - the chrome.fileSystem API simply provides another DirectoryEntry, but the rest of working with it is pretty much the same.
I've been struggling to get this working for too long. I just started to get into PhoneGap/Cordova. I got the demo app running, installed all official plugins, and added this SQLite plugin to begin work with: https://github.com/brodysoft/Cordova-SQLitePlugin
However, I want the plugin to read a pre-packaged database. Simply put, create an app that works offline and does not need to download an SQLite database when it is run for the first time.
I have been developing for Android for quite some time, and the solution was to deploy a read-only database file in the assets folder, and on first run copy the database file into a different folder, where I can read/write as I please.
So I did a little research and realized that it SHOULD be the same with PhoneGap. Place a binary SQLite database somewhere, so that when built, it will be packaged with the app. And then simply load it with the SQLite plugin I linked here.
Finally, the question! What are the exact steps I have to take to be able to read a file that was packaged with the app?
Where should I put my binary file to ensure that it gets packaged into the app?
How exactly should I initialize the File API? Should I ask for persistent storage using window.requestFileSystem? Or should I get some (not sure which) directory (cordova.file.applicationDirectory) as a DirectoryEntry using window.resolveLocalFileSystemURL? If so, what are the EXACT parameters I should use? I am mostly referring to this: https://github.com/apache/cordova-plugin-file/blob/master/doc/index.md
How do I read the packaged file? Using window.resolveLocalFileSystemURL with the right folder? What should then the parameters be?
File copying should work OK if I get to this point. Just copy from the read-only cordova.file.applicationDirectory into cordova.file.dataDirectory, which is read/write. Right?
I know the questions might be pretty basic, but my countless attempts were unsuccessful and I did not find a tutorial that explains this in-depth (believe me, I googled). Also, the documentation seems insufficient.
Just working with a WebSQL database and load data the DB using a s***load of INSERTs is not a viable option, the database has thousands of records.
Thanks for the help in advance, you will save me a headache or two.
Currently Cordova's standard SQLite Plugin supports Pre-populated Databases, which will copy your database file from www and put it into the right directory. It also supports Android as well as iOS, so you don't need to have different logic for different platforms.
When you open the database, you can specify that it is pre-populated using createFromLocation: 1 like this:
var db = window.sqlitePlugin.openDatabase({
name: "my.db",
createFromLocation: 1
});
For iOS, it will first check www and if the file exists, it will copy it to Documents. Keep in mind that it will be backed up by iCloud. If you want to exclude it from iCloud, then add location: 2 on openDatabase as well, which will put your databases in Library/LocalDatabase.
UPDATE (2016)
The original Cordova-sqlite-storage project does not support pre-populated db anymore.
However, this feature just moved to another project from the same creator. Now, use Cordova-sqlite-ext for this purpose.