How to use Charts on mobile is one of those areas where everyone has an opinion.  Usually these approaches boil down to the use of a WebView or taking a dependency on a 3rd party native framework.

Usually I recommend using a WebView as the web charting tools tend to provide a greater level of functionality. But recently I discovered JBChartView by Jawbone which changed my mind.  JBChartView  provides charting functionality I typically use bundled in an easy to use native iOS (sorry not android version) project.

To make JBChartView consumable by Titanium I’ve wrapped the project into a module, Ti.JBChart , and created Titanium specific documentation and examples.  The below animated gif shows the Ti.JBChart examples in action.

In Action

An example

The Ti.JBChart  github project has examples for Bar, Line, and Area charts.   The following snippet shows an example on how to use the LineChartView in your Titanium project.

    function createData(){
        var result =[];
        function createRandom(min,max){
            return Math.floor(Math.random()*(max-min+1)+min);
        }   
        for (var iLoop=0;iLoop<12;iLoop++){
            result.push(createRandom(1,12));
        }
        return result;
    }

    var data = [];
    //Add first line chart
    data.push(createData());
    //Add second line chart
    data.push(createData());

    var myStyles = [];
    //Create the first line chart with a solid  line
    myStyles.push(chart.CHART_LINE_SOLID);
    //Create the second line chart as a with a dashed line
    myStyles.push(chart.CHART_LINE_DASHED);

    var lineChart = chart.createLineChartView({
        width:Ti.UI.FILL, height:250, 
        data : data,
        toolTipData : ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'],
        selectedLineColors :['yellow','orange'],
        lineColors:['green','blue'],
        styles : myStyles,
        selectionBarColor:'purple',
        chartBackgroundColor:'#404041'
    });

Looking for more?

• Visit the Ti.JBChart project on Github here.
• Read the documentation here.
• Get the example app here.

Starting with Titanium 3.3.0.GA Appcelerator has updated their module templates to have a new default folder structure.  Along with these directory changes you will notice that you get a permission error when running the ./build.py script, usually something like the error shown below.

To fix this you simply need to run the chmod 755 build.py command in terminal as shown below.

This updates build.py to have the correct permissions so that you can continue your building by running build.py as you’ve always done.

Since the release of iOS7, the Live Blur effect has been extremely popular.  Since Apple doesn’t yet provide this effect natively the community has come up with a few different approaches to achieve this effect.

Toolbar Layer

One common approach to achieving a live blur is to use a layer from the UIToolbar.  This allows you to use the same live blur effect that a IUToolbar has, but with the same functionality of a UIView.  This approach is reliable with good performance.  The downside, is you have no control over the Blur and in iOS 7.1 the blur was made softer making it difficult to see when used in come color schemes. Adrian  Opaladini has created an excellent Titanium module called Live BlurView which implements this approach. If you are looking at implementing a light live blur I highly recommend checking out this module.

Timer Driven

The next approach to implementing a live blur effect is to use a timer and a blur algorithm or library such as GPUImage.  Typically this is implemented using a timer which at a specific duration takes a snapshot of the source view and applies a blur effect.  As you can imagine the downside to this approach is you need to implement the refresh code yourself.   This usually requires managing the processes of a timer, view snapshot, and image processing.  Not a ton of code, but you don’t get anything out of the box. The upside, is complete control over the process.  This allows you to use the blur effect that looks best in your app, at a frequency that makes sense. There is an example of how to do this using the Ti.BlurView module here.

Another Option…

I really wasn’t happy with either the Toolbar or Timer approaches.  I wanted more control then I had with the Toolbar approach, but the idea of firing a timer when it wasn’t needed wasn’t appealing, especially considering the performance impact.  This got me thinking, that for many Titanium apps, the UI fires all types of events when the application state has changed.  Why not hook into these events. Out of this came the Scroll Blur example for the Ti.BlurView module.

See it in action

The Code

var mod = require('bencoding.blur');
	
exports.createWindow = function(){	

	var win = Ti.UI.createWindow({
		backgroundColor:'blue',
		barColor:"#999", title:"Blur on Scroll"
	});

	function createRows() {
	
	    function buildRow(el) {
	        var row = Ti.UI.createTableViewRow({
	            width:150, height:120
	        });
	
	        var headerImage = Ti.UI.createImageView({
	            image: el.image, 
	            width:Ti.UI.FILL, height:Ti.UI.FILL
	        });
	
	        var titleLabel = Ti.UI.createLabel({
	            text: el.title,
	            width: Ti.UI.FILL, height: '30dp', 
	            color:'green',
	            horizontalWrap: false, bottom: '5dp', 
	            left: '5dp', right: '5dp',
	            font: {
	                fontSize: '20dp', fontWeight:'bold'
	            }
	        });
	
	        row.add(headerImage);
	        row.add(titleLabel);
	        return row;
	    };
	
	    var rows=[];
	    for (var iLoop=0;iLoop<100;iLoop++){
	        rows.push(buildRow({ title: 'Test Row '+iLoop, 
	        					image: 'cat.jpg'}));
	    }
	    return rows;
	};

	var list = Ti.UI.createTableView({
	    width:Ti.UI.FILL,  height:Ti.UI.FILL, data:createRows()
	});
	win.add(list);

	var imgView = mod.createGPUBlurImageView({
		height:250, width:Ti.UI.FILL, zIndex:500,top:0,
		blur:{
			type:mod.IOS_BLUR, radiusInPixels:1
		}		
	});
	win.add(imgView);	

	var w = Ti.Platform.displayCaps.platformWidth;
	var blur = {
		timerId: null,
		apply : function(){
			Ti.API.debug("Taking screenshot");
			var screenshot = list.toImage();
			Ti.API.debug("applyBlur : Cropping screenshot");
			screenshot.imageAsCropped({x:0,y:0, height:250,
										width:w});
			Ti.API.debug("set screenshot as image to ImageView");
			imgView.image = screenshot;
			Ti.API.debug("set blur so we will update");
			imgView.blur={
				type:mod.BOX_BLUR, radiusInPixels:5
			};	
			Ti.API.debug(" Done with Blur");				
		}		
	};
		
	list.addEventListener('scroll',function(f){
		Ti.API.debug("action fired : scroll");
		
		if(blur.timerId!=null){
			Ti.API.debug("Timer already set, returning");
			return;
		}
		
		blur.timerId = setTimeout(function(){
			blur.apply();
			blur.timerId = null;	
		},50);	
			
	});

	list.addEventListener('scrollend',function(f){
		Ti.API.debug("action fired : scrollend");
		
		if(blur.timerId!=null){
			Ti.API.debug("Clearing Interval");
			clearInterval(blur.timerId);
			blur.timerId = null;
		}
		blur.apply();	
	});
 	 		
	win.addEventListener('open',function(f){
		blur.apply();
	});

	win.addEventListener('close',function(f){
		if(blur.timerId!=null){
			clearInterval(blur.timerId);
		}	
	});
		
	return win;
};

Looking for a high performance way to apply Blur effects?  The latest release of the Ti.Blur module provides the new high performance GPUBlurImageView component.  GPUBlurImageView is an extended version of the Ti.UI.ImageView with one extra  property, blur.  Through this single property you can apply iOS, Box, or Gaussian blur effects.

Initial tests show a 50% performance improvement over the prior Ti.BlurView blur functionality.  If you have a retina display on your mac you will find the GPUBlurImageView renders faster on device then in the simulator due to the number of pixels being rendered.

iOS Blur Code Example:

var mod = require('bencoding.blur');

var imageView = mod.createGPUBlurImageView({
    height:Ti.UI.FILL, width:Ti.UI.FILL,
    image:"42553_m.jpg",
    blur:{
        type:mod.IOS_BLUR, radiusInPixels:1
    }
});

See the BlurView in action:

Looking to implement a day and night mode to your app?  Ti.Brightness provides a series of APIs that allows you to read the iOS 7 screen brightness and be notified if it changes.

Getting the screen brightness

Reading the iOS 7 screen brightness level is easy.  Just call the getScreenBrightness method as shown below.  This method provides Titanium access to the underlying iOS [UIScreen mainScreen].brightness platform API.

var brightness = require('ti.brightness');
var level= brightness.getScreenBrightness();
Ti.API.info("Brightness Level:" + level);

* If you are running this in the simulator, 0.5 will always be returned.

Brightness Changed Event

You can use the changed event as shown in the following snippet to trigger an event after the user has adjusted their screen brightness. This event provides Titanium access to the name UIScreenBrightnessDidChangeNotification notification.

function onBrightChange(e){
    Ti.API.info(JSON.stringify(e));
    alert("Your Screen brightness is level: " + e.brightness);
};

brightness.addEventListener('changed',onBrightChange);

* This event will not trigger in the simulator

In Action

The following movie shows the module in action and how Ti.Brightness can be used to add a dark and light theme to your app.