FlxScrollableArea

For users of HaxeFlixel 4.0.0+, a scrollable area with automatic scrollbars, originally created for manual layout enthusiasts (i.e. users of FlxG.scaleMode = new StageSizeScaleMode()) to solve age-old problems when resizing with scrollbars, but it works with the default scalemode too.

See here for screenshots.

See here for an animated GIF.

1. This has been tested mostly on desktop targets and only with OpenFL legacy.
2. OpenFL 3.6.1 + Lime 2.9.1 work (that's all that's current supported in HaxeFlixel), but some older versions should work, too.
3. haxe 3.2.1 and 3.4.0 work.
4. OpenFL Next (openfl test neko -Dnext, for example) passes the unit tests, but the example app's boxes look pretty strange due to https://github.com/HaxeFlixel/flixel/issues/2026 . That said, the scrollbar still functions, so it may work fine for your OpenFL-Next-enabled project.

Let me know if other combinations work too!

How do I install it?

Using haxelib, you can start with the latest release like so:

haxelib install flxscrollablearea

How do I run the example?

Switch to the installed directory of FlxScrollableArea. If you installed via haxelib as above (rather than git clone or github download), you can do this:

haxelib path flxscrollablearea

Then take the first line of the output, and cd there, then:

cd example
lime test neko

You should see something with workable scrollbars like the following:

How do I use it in my own project?

Reference it in your Project.xml:

<haxelib name="flxscrollablearea" />

In a state where you want a scrollable area, import it:

import ibwwg.FlxScrollableArea;

Now, prepare the content of your scrollable area off-screen somewhere where no other camera will reach it. Then in your state's create():

	_myScrollableThingie = new FlxScrollableArea( new FlxRect( 0, 0, Lib.current.stage.stageWidth, Lib.current.stage.stageHeight ), // full-screen viewport
		new FlxRect( _offscreenX, 0, width_of_my_content, height_of_my_content ), FIT_WIDTH );
	FlxG.cameras.add( _myScrollableThingie );

Pro tip: If you use a FlxSpriteGroup for your off-screen content, then in the constructor (and below in onResize), you can just use myOffscreenGroup.getHitbox() instead of making a new FlxRect yourself.

If you're not using StageSizeScaleMode, you're done!

Everything up to this point can be found in the demo in the example directory. Simply cd there and run lime test neko.

StageSizeScaleMode

In your state's onResize(), follow this basic pattern for each scrollable area:

	_myScrollableThingie.viewPort = new FlxRect( 0, 0, Lib.current.stage.stageWidth, Lib.current.stage.stageHeight ); // must be before .bestMode
	if (_myScrollableThingie.bestMode == FIT_WIDTH) {
		// resize your content so that it will fit the width of your newly resized viewport, minus _myScrollableThingie.verticalScrollbarWidth
	} else { // FIT_HEIGHT
		// resize your content so that it will fit the height of your newly resized viewport
	}
	_myScrollableThingie.content = new FlxRect( _offscreenX, 0, width_of_my_content, height_of_my_content );

Voila, you should have a sensibly drawn, functional vertical scrollbar, only when necessary.

Does it support FlxSubState with a paused parent state?

Yes. Just pass your substate in the constructor so that it doesn't default to FlxG.state. (This is so the scrollbars themselves, which get drawn outside the viewport by being added to the given FlxState, will still work when your parent state's drawing and/or updating is paused.)

Showcase

FlxScrollableArea is used in the following games:

1. Willy and Mathilda's Houseboat Adventure: The Game
2. Debatcles (unreleased)
3. Your next hit! ;)

Please let me know if you make something using FlxScrollableArea and would like to feature it here. :)

Running tests

In FlxScrollableArea's project root, simply run:

lime test neko

Coverage may be obtainable like this:

haxelib run munit t -coverage

...but it may be platform-dependent, and may require tweaking test.hxml to use the right versions and point correctly to your openfl externs.

Special note for users of the deprecated "scrollable-area" haxelib

Please note that I phased out the gimmicky classpath, so if you're upgrading to 0.1.0 or beyond, you'll need to search and replace gimmicky. with ibwwg..

I had trouble deprecating the old publishing name with haxelib, but then discoverd if you use git bisect, the name change will have broken your old builds. If this is the case for you, first downgrade to pre-rename scrollable-area:

haxelib set scrollable-area 0.0.2-alpha

Then install and use the new one going forward. (See "How do I use it?".)

Unfortunately if you used 0.1.1 for a few commits, those will still be broken. But those before and those after will be good to go, which will hopefully be the majority. Eventually, I suppose. :)