Extending the animation.js Alloy builtins

slideIn.js

/**
 * @method slideIn
 * Makes the specified view appear using a "slide-in" animation, it will automatically
 * detect where the view is offscreen and bring it into the user's vison.
 * @param {Titanium.UI.View} view View to animate.
 * @param {Number} duration Fade duration in milliseconds.
 * @param {function()} [finishCallback] Callback function, invoked after the popIn completes.
 */
exports.slideIn = function (view, duration, finishCallback) {
	
	var xValue, yValue;
	
	if (view.top && view.top.indexOf('-') != -1) {
		yValue = view.top.substring(1);
	} else if (view.bottom && view.bottom.indexOf('-') != -1){
		yValue = view.bottom;
	} else {
		yValue = '0dp';
	}
	
	if (view.left && view.left.indexOf('-') != -1) {
		xValue = view.left.substring(1);
	} else if (view.right && view.right.indexOf('-') != -1){
		xValue = view.right;
	} else {
		xValue = '0dp';
	}
        
    if (OS_ANDROID) {
    	xValue = parseInt(xValue.replace(/[a-z-]gi/, "")) * Ti.Platform.displayCaps.dpi / 160;
    	yValue = parseInt(yValue.replace(/[a-z-]gi/, "")) * Ti.Platform.displayCaps.dpi / 160;
    }
        
    var transform = Titanium.UI.create2DMatrix();
    transform = transform.translate(xValue, yValue); // Looks like I can't do this one in one line
	
	var animation = Titanium.UI.createAnimation({ 
		"transform": transform, 
		"duration": duration
	});
	
	if (finishCallback) {
		view.animate(animation, finishCallback);
	} else {
		view.animate(animation);
	}
};

Hmmm Android doesn't like 'dp' values on the transform (pretty weird...) making a fix

This won't "slideIn" from the sizes (not automatically though) maybe I should just let the user pass in the values for X and Y like on Animator?