Download files and store them locally with Phonegap/jQuery Mobile Android and iOS Apps

Use FileTransfer.download, here is an example:

function downloadFile(){window.requestFileSystem(LocalFileSystem.PERSISTENT, 0,     function onFileSystemSuccess(fileSystem) {        fileSystem.root.getFile(        "dummy.html", {create: true, exclusive: false},         function gotFileEntry(fileEntry) {            var sPath = fileEntry.fullPath.replace("dummy.html","");            var fileTransfer = new FileTransfer();            fileEntry.remove();            fileTransfer.download(                "http://www.w3.org/2011/web-apps-ws/papers/Nitobi.pdf",                sPath + "theFile.pdf",                function(theFile) {                    console.log("download complete: " + theFile.toURI());                    showLink(theFile.toURI());                },                function(error) {                    console.log("download error source " + error.source);                    console.log("download error target " + error.target);                    console.log("upload error code: " + error.code);                }            );        }, fail);    }, fail);};}

This is how I solved it. First set the file paths, wich are different for Android and iOS

var file_path;function setFilePath() {    if(detectAndroid()) {           file_path = "file:///android_asset/www/res/db/";        //4 Android    } else {        file_path = "res//db//";        //4 apache//iOS/desktop    }}

Then I load my JSON files, wich are prepackaged with the app, into the local browser storage. Like this:

localStorage["my_json_data"] = loadJSON(file_path + "my_json_data.json");function loadJSON(url) {    return jQuery.ajax({        url : url,        async : false,        dataType : 'json'    }).responseText;}

If I wanna update my data. I get the new JSON Data from the server and push it into the local storage. If the server is on a different domain, which is the case most of the time, you have to make a JSONP call (check jQuery's docs on JSONP). I did it kinda like this:

$.getJSON(my_host + 'json.php?function=' + my_json_function + '&callback=?', function (json_data) {    //write to local storage    localStorage["my_json_data"] = JSON.stringify(json_data);});

You can do this in one line of code:

new FileManager().download_file('http://url','target_path',Log('downloaded success'));

target_path: can include directory (example: dira/dirb/file.html) and the directories will be created recursively.

You can find the library to do this here:

https://github.com/torrmal/cordova-simplefilemanagement