DWURecyclingAlert

Optimizing UITableViewCell For Fast Scrolling

Code Quality Rank: L4

Programming language: Objective-C

License: MIT License

Tags: Code Quality    

README

DWURecyclingAlert

Your code usually has less than ten milliseconds to run before it causes a frame drop.1

[][license]

Visualize Bad Drawings On The Fly

Injects 4 classes:

• UITableViewCell
• UICollectionViewCell
• UITableViewHeaderFooterView
• UICollectionReusableView (as footers/headers)

Monitors 6 time sensitive API calls:

• [UIView drawRect:]
• tableView:cellForRowAtIndexPath:
• tableView:viewForHeaderInSection:
• tableView:viewForFooterInSection:
• collectionView:cellForItemAtIndexPath:
• collectionView:viewForSupplementaryElementOfKind:atIndexPath:

Visualizes bad drawing code in 2 ways:

• Displays non-recycled UIView, CALayer and UIImage objects with bold red bolders.
• Displays the time it takes to complete each time sensitive API calls, in milliseconds.

Usage

Step 1: Drop [DWURecyclingAlert.m][code] into your project, Swift or ObjC.

Step 2: There's no step 2.

(Optionally) Using CocoaPods and manually start the injection:

pod 'DWURecyclingAlert'

Then manually start injection by running the following function anywhere in your project:

void Inject_DWURecyclingAlert();

UI Configuration

It's likely that your project happens to use lots of [UIColor redColor] here and there. Or, maybe you want to localize the millisecond warning string with your team's first language. Take a look at the [UI Configuration][code_line_39] section and customize them the way you like.

How It Works

Method swizzling and associated objects. You could always read the [source][code].

Disabled in Release By Default

[DWURecyclingAlert.m][code] requires the DEBUG macro to compile and run. As a result, it's disabled in Release by default. If you also want to disable it in debug builds, comment out the [DWURecyclingAlertEnabled][code_line_23] macro at the top of the file.

Misc

• Whether your cell / header / footer are created by code or by nib/storyboard, [DWURecyclingAlert.m][code] has a way to scan it.
• It's perfectly normal for a cell to have multiple subviews that override drawRect:, if that's the case, [DWURecyclingAlert.m][code] will calculate the sum for all the time it takes to go through each drawRect: call.
• [DWURecyclingAlert.m][code] requires iOS 6 or higher to compile.

Example Project

Inside this repo you can find the RecyclingAlert example project.

License

DWURecyclingAlert is released under the MIT license. See [LICENSE][license] for details.

1: Facebook AsyncDisplayKit Guide. (http://asyncdisplaykit.org/guide)