Fabric.js: canvas.clear() makes the canvas background transparent

[paulcredmond]

Version

1.6.5+

Test Case

https://jsfiddle.net/6z5vay2e/

Steps to reproduce

Clear the canvas using canvas.clear()

Expected Behavior

canvas.clear() does not affect the background color

Actual Behavior

canvas.clear() removes the canvas background color

[paulcredmond]

It's possible to set the background colour and render the canvas after it has been cleared, I'm just wondering why this is happening now. This wasn't present in earlier versions.

[cmnt]

Hello,

This is normal behavior : http://fabricjs.com/docs/fabric.Canvas.html#clear

Clears all contexts (background, main, top) of an instance

I prefer that it keeps the background...
I wondering too

[asturur]

Well, i did not write that function in first place.
One user some weeks ago came here and complained the opposite.
Then i read the jsdoc part and it said that cleared everything, and i just did it.

So in my opinion, clear is ok like it is.
On canvas we objects, background, backgroundColor, overlya, overlaycolor.
Everyone of them can be cleared setting a property, so either clear does everything or it does not have any reason to exist.

I m open to discussion anyway.

[stephenkillingsworth]

I would definitely say if canvas.clear() clears all properties, then there needs to be another function, like canvas.clearObjects(), to handle the far-more-typical use case of simply removing all objects from the canvas.

[asturur]

does not canvas.remove(canvas.getObjects()) work?

On Oct 18, 2016 18:40, "stephenkillingsworth" [email protected]
wrote:

I would definitely say if canvas.clear() clears all properties, then there
needs to be another function, like canvas.clearObjects(), to handle the
far-more-typical use case of simply removing all objects from the canvas.

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[asturur]

no, it does not, and you cannot do

canvas.forEachObject(function(o){
  o.remove();
})

is really a minor annoyance i have to say.

[paulcredmond]

In my mind I would think the clear() method would delete all objects and not the canvas properties. There is some subjectivity here, but I understand that is by design and so is not a bug.

[cAstraea]

Can we have a parameter for this without removing the background ? Like in previous 1.5 version ? http://jsfiddle.net/InferOn/fx05t621/2/

[asturur]

Well to remove all objects and nothing else you can still do canvas.remove(...canvas.getObjects().concat()) or canvas.remove.apply(canvas, canvas.getObjects().concat()) too many flags or options are complicated.

[milahu]

Well to remove all objects and nothing else you can still do canvas.remove(...canvas.getObjects().concat()) or canvas.remove.apply(canvas, canvas.getObjects().concat())

thanks for the snippet, can we add this to the docs of canvas.remove() ?

or add a "trivial convenience function", like stephenkillingsworth suggested,
"like canvas.clearObjects()" or like canvas.removeAll()

also, why do we need concat() ?
why cant we just say canvas.remove(...canvas.getObjects()) ?
concat makes no difference in my case

also we should set canvas.renderOnAddRemove = false for this, no?

[asturur]

concat is not needed, since long getObjects() returns always a new array.

concat() with no arguments is a quick way to return a copy of an array, similarly to slice(0).

[oroafrica]

why not just create a new canvas and initialize with original properties