Hey Aaron, very cool stuff, looking forward to checking it out!
Question: any performance hit on the app by using Capture? What's the expected throughput on images taken in this way (given a particular device, say Galaxy Nexus)? - Lorin On Tue, Mar 12, 2013 at 11:30 AM, Aaron Charbonneau <amcha...@gmail.com>wrote: > Glad you like it :) > Yes in fact the actual capture makes use of View.capturePicture() which > actually grabs the entire document, then that can be clipped down to the > size/location of a specific element. > > -Aaron > > > On Tue, Mar 12, 2013 at 11:27 AM, Michal Mocny <mmo...@chromium.org> > wrote: > > > Aaron, > > > > I haven't even begun looking at your implementation, but I'm just going > to > > say it: this is awesome! > > > > First question: When Capturing a DOM element, can you capture 'body' to > > grab it&children for a "full content screenshot", or does it have to be a > > specific single element? > > > > -Michal > > > > > > On Tue, Mar 12, 2013 at 1:58 PM, Aaron Charbonneau <amcha...@gmail.com > > >wrote: > > > > > Greetings! My name is Aaron Charbonneau, happy to be a new member of > the > > > mailing list! > > > > > > I have been developing a sceenshot plugin for Cordova to help > facilitate > > > automation testing and debugging of Cordova apps, and I would love some > > > feedback on it. Currently Cordova provides a bunch of native functions > > > that allow you to do some cool stuff, but not much functionality to > test > > > the apps that make use of them. Being able to take a capture of the > > screen > > > from within you app is a great way to automate testing or get > additional > > > information for debugging an issue. Since there is no > > > Javascript mechanism for taking screen captures the solution would have > > to > > > be native, which fits nicely into the "gap" that Cordova/Phonegap > > bridges. > > > Any medium to large scale app can benefit greatly from automation > > testing > > > and any app can benefit from an extra debugging tool, and that is what > I > > > hope this screenshot plugin can help achieve. > > > > > > Currently the plugin offers 2 functions: > > > > > > Capture(): > > > * Take a capture of the current view, write that capture to a .png file > > > with the specified file name and sub directory of the sdcard (fallback > to > > > emulated sdcard in the case there isn't an sdcard mounted) > > > * Able to create a sub-screenshot with a specified rectangle in order > to > > > block out ui elements that may be variable, and also save space. > > > * Can take captures of images/dom elements (including canvas) that are > > > lager than the actual screen size > > > > > > CaptureAndCompare(): > > > * All the functionality of Capture() > > > * Perform a comparison between the captured image and a baseline image > > > located at the specified location in either the assets folder or the > > > sdcard. > > > * User can specify per color channel tolerances as well as total pixel > > > tolerances to avoid false positives for the inevitable rendering > > > differences across devices. > > > * Optionally output a png file that contains the differences between > the > > > actual and the baseline for debugging/triage purposes, two modes: > binary > > > diff (all failing pixels appear as solid white) or the true differences > > > between pixels. > > > > > > If you can spare some time, I would love it if you could take a look at > > the > > > api and parameters I have defined to make sure they adhere to Cordova > > > plugin best practices. The most crucial part would be in the plugin > > itself > > > at ScreenCapture.java: > > > > > > > > > https://github.com/Charbs09/Cordova-Mobile-Spec-ScreenCapture/blob/master/src/org/apache/cordova/plugin/ScreenCapture.java(capture() > > > and captureAndCompare() are the two exposed functions) > > > > > > I'm also interested to know you thoughts on it's usage. I started with > > the > > > mobile-spec testing framework and put some quick rendering tests into > the > > > Autotest section as a viable use case. In order to get the WebView > into > > > the state I wanted to capture, I had to implement a wait timer to allow > > the > > > view to update before taking the capture. Once the wait function > > > completes, the capture can be taken and everything from there is > callback > > > based. I use the Jasmine waitsFor()/runs() blocks to make the tests > run > > > synchronously. For some validation testing I made a compare function > in > > > Javascript to run against the native compare. Turns out Java runs alot > > > faster than Javascript (surprise!) thus the native compare is about > 2-5x > > > faster. All in all the process is fairly quick, the full > > captureAndCompare > > > with 3 file io's takes about 233ms on a Nexus One, and ~100ms on a > Nexus > > 10 > > > (256x256 image size). > > > > > > Anyways here is the usage: > > > > > > > > > https://github.com/Charbs09/Cordova-Mobile-Spec-ScreenCapture/blob/master/assets/www/autotest/tests/rendering.tests.js > > > > > > And here's the JS wrapper for the plugin calls: > > > > > > > > > https://github.com/Charbs09/Cordova-Mobile-Spec-ScreenCapture/blob/master/assets/www/screencapture.js > > > > > > Thanks for your time, and I look forward to ANY feedback positive or > > > negative. > > > > > > Thanks, > > > Aaron > > > > > >
