PhoneGap + AngularJS无法读取刚刚创建的文件

Question

I'm using AngularJS in a PhoneGap 3.5.0 project and I use it on iOS 5 and 6 from XCode.

I try to read a file that I write previously. But I've always an empty string instead of the value of response which is a JSON.

$http.get(API + '/content')
.success(function (response) {
    // response is a JSON
    console.log(response);

    window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function (filesystem) {
        filesystem.root.getDirectory('json', {create: true}, function (dirEntry) {
            dirEntry.getFile('contents.json', {create: true, exclusive: false}, function (fileEntry) {
                fileEntry.createWriter(function (fileWriter) {
                    fileWriter.onwriteend = function (e) {
                        // this is not working...
                        fileEntry.file(function (file) {
                            var reader = new FileReader();

                            reader.onloadend = function (e) {
                                // e.target.result is an empty string (!?)
                                console.log(e.target.result, typeof e.target.result);
                            };

                            reader.readAsText(file);
                        });
                    };

                    fileWriter.write(response);
                });
            });
        });
    });

});

Answer 1

I have this working version which works with photos:

window.requestFileSystem(LocalFileSystem.PERSISTENT, 0, function(fileSystem){
                fileSystem.root.getDirectory("photos", {create: true, exclusive: false}, function(dir) {
                    dir.getFile("photo_"+Date.now()+".jpg", {create: true, exclusive: false}, function(fileEntry){
                        fileEntry.createWriter(function(writer){
                            writer.onwriteend = function (evt) {
                                scope.processPhoto(fileEntry.toURL(), $(element).index());
                            };
                            writer.write(element.find('input')[0].files[0]);
                        }, fail);
                    }, fail);
                }, fail);
            }, fail);

the function that handles fail is

function fail(error) {
            console.log(error.code);
        }

I cannot see too much difference in why mine works and your does not, but try using the fail function to drill down to the possible error code and cause particular to your case.