Write to an external file Android

file.js

var win = Ti.UI.createWindow({backgroundColor: 'white'});
var dir = Titanium.Filesystem.getFile(Titanium.Filesystem.externalStorageDirectory);
Ti.API.info(dir.nativePath);

var testfile = Ti.Filesystem.getFile(dir.nativePath, 'text.txt');
testfile.write('Hello');
Ti.API.info('external directoryListing = ' + dir.getParent().getDirectoryListing());
Ti.API.info('text.txt exists? ' + testfile.exists());
Ti.API.info('text.txt size: ' + testfile.size + ' bytes');

Ti.API.info("------------");
Ti.API.info("Test file contents:\n" + (testfile.read()).text);
alert(testfile.nativePath);
win.open();

imageToFile.js

var win = Ti.UI.createWindow({backgroundColor: 'white'});
var dir = Titanium.Filesystem.getFile(Titanium.Filesystem.externalStorageDirectory);
var file ;

Titanium.Media.showCamera({

	success:function(event)
	{
		var cropRect = event.cropRect;
		var image = event.media;
		
		Titanium.Media.saveToPhotoGallery(image);
		if(Titanium.Filesystem.isExternalStoragePresent) {
			// create a new file
			file = Titanium.Filesystem.getFile(dir.nativePath, 'image.png');
			file.write(image);	
			alert(file.read() + ' ' + file.size + ' ' + file.nativePath);
			Titanium.UI.createAlertDialog({title:'Photo Gallery',message:'Check your photo gallery'}).show();		
			imageView.image = file.read();
			win.add(imageView);
		}
	}
});

var imageView = Ti.UI.createImageView();
win.open();