Readers of this post have raised issues with the plugin. I have to personally check for the issues but while using the plugin if you find any issues, you might want to debug it in ADT. I will come up with a working plugin soon. Thanks.
Sometime back I worked on a Phonegap Android plugin that helps to save an HTML5 Canvas Image to the device’s gallery. Well, the title of this post may be misleading but note that when you save an image, you actually have to save it on the SD Card or the device’s memory. The Gallery is just an app that shows the collection of images from various locations on the SD Card. So, there’s nothing like saving an image directly to the Gallery.
I had this working with Phonegap 2.2.0 (the version that I used). Newer versions of Phonegap/Cordova are available and things might have changed a bit, specially in the way custom plugins are written. Hence, if you are using newer versions of Phonegap you should have a look at the official documentation before proceeding.
Note that I am not a Java developer, and there may be better ways of writing this plugin.
How to install the plugin?
You need to get hold of two files :
1) The Java class – SavePhotoPlugin.java
Alright, now back to the detection code. Just copy/paste this inside your window load / body load or in case of JQuery the $(document).ready() method,
document.write('Your browser does not support SVG!');
So, if your browser does not support SVG, then it will not process further (in case your application cannot live without SVG). But if you have a back up plan and you can live without SVG in your browser, then you can add an else block along with the if so that you can write your backup logic.
Well, the code is very simple. Inside the if condition I create a SVG element using the standard DOM createElement() method. Now this will create a <svg></svg> object. Now next thing I do is to check if the getAttributeNS() method is defined or not. If you browser does not support <svg> then there is no way it will understand getAttributeNS() and that’s the catch.
Here is the code,
var canvasEl = document.createElement('canvas'); //create the canvas object
if(!canvasEl.getContext) //if the method is not supported, i.e canvas is not supported
document.write("HTML5 Canvas Not Supported By Your Browser");
As you can see in the first line I create a HTML5 Canvas element by using createElement() DOM method. As you might know that to work with Canvas, you have to get it’s context object (2d for now), which can be retrieved by the getContext() method. So, if a browser does not support the <canvas> tag or the canvas element, then no way the getContext() method will be defined for it. That’s what I check in the second line – the if condition. Remember that a function/method name is a variable which holds a reference to the function block. So we can check whether it is defined or not, in a normal way like we do for object properties. IE8 doesn’t support HTML5 Canvas. So try this code in IE8 for a quick test.
How can I use it with my code?
Use this code block inside the window load event handler or when the DOM ready event is triggered (using document.onreadystatechange, more). You can modify it as per your need.
Leave behind a comment if you are upset with this attempt.
In this post I have a similar example but this time multiple pop ups can be opened from the same page. Opening multiple pop up’s from a single page was requested by some of my readers. And here it is. I will not go deep into explaining the bits and parts of how to create a pop up window. You can go through my previous post for that. But first let’s check a demo (meant only for web-kit based browsers):
How to run this in Firefox, IE and other browsers?
For this you need to make changes in the CSS file. Add CSS3 prefixes for other browsers similarly as it is there for -webkit- . CSS3 junkies would already know what I am talking about.
For those who wanted a vertical swiping feature to the the swipe gesture gallery that I created earlier, this post has a new demo and minimal explanation about a vertical swipe gesture gallery. Now you can swipe the images up or down.
I will not go through the basics once again as I have explained them in details in my previous posts. You can refer them once again in these two tutorials – post 1, post 2. Check out the demo below. Open the link in a webkit browser in either your mobile device or your computer.
I have been working on a Phonegap based Android app which involves the HTML5 Canvas. So this is what I had been trying for some time – get a png/jpeg image of the Canvas (its a Canvas paint app, something like this and I want to get an image of the drawing..) and then upload the image to Facebook on a user’s album. Let me tell you, it has been a heck of a task and around 15-20 days of restlessness.
This is another update to the regular swipe gesture gallery that I created in two of my earlier post – post1, post2. This time I have implemented the looping feature for the images. The gallery never ends, instead you swipe it in a circular motion. So, whenever you reach the end of the list, swipe again from right to left across your device’s screen to see the first image and also when you reach the beginning of the list you swipe from left to right of your device’s screen to see the last image again. Try out the demo first and you will get a feel of it. Check out the demo in a webkit desktop browser (Chrome, Safari) or an iOS/Android device’s browser. Click on any image to open a URL as well. So, click/tap to open URL is included.
Here’s a sneak peak at the touch version of the Coverflow animation. The app is fully touch enabled, you can swipe across the screen to move the images or tap on any image individually to move it. The app works fine in iPhones, iPod touch and iPad’s. Have not tested it in Android 4.0 or greater. Since iOS browsers supports CSS3 3D transformations so it runs very smooth. In Androids < 4.0 it gives a horrible look n feel.
Here’s the link to the demo. Check in an iOS device (open up in mobile safari),
But, still to support different device screen sizes you will need to make changes to the CSS or the asset (images) sizes. The demo that I have worked on, I have considered the iPhone resolution – 320 x 416.