Adding Custom Delete (Back,toFront) Button to Controls

Question

I would like to know if there is an easy way to add a delete, bring to front, bring to back function into the existing fabric.js object controls.

A

Answer 1

You can overwrite the __onMouseDown function for example like this.

the target object contains __corner element target.__corner

Check if this is 'tr' (top right) and delete activeObject

    if (target.__corner === 'tr') {
        if(canvas.getActiveObject()){
            canvas.remove(canvas.getActiveObject());
        }
    }

Full code:

fabric.Canvas.prototype.__onMouseDown = function (e) {

    // accept only left clicks
    var isLeftClick  = 'which' in e ? e.which === 1 : e.button === 1;
    if (!isLeftClick && !fabric.isTouchSupported) {
        return;
    }

    if (this.isDrawingMode) {
        this._onMouseDownInDrawingMode(e);
        return;
    }

    // ignore if some object is being transformed at this moment
    if (this._currentTransform) {
        return;
    }

    var target = this.findTarget(e), 
    pointer = this.getPointer(e, true);

    if (target && target.__corner === 'tr') {
        if(this.getActiveObject()){
            this.remove(this.getActiveObject());
        }
    } else {
        // save pointer for check in __onMouseUp event
        this._previousPointer = pointer;

        var shouldRender = this._shouldRender(target, pointer),
          shouldGroup = this._shouldGroup(e, target);

        if (this._shouldClearSelection(e, target)) {
            this._clearSelection(e, target, pointer);
        } else if (shouldGroup) {
            this._handleGrouping(e, target);
            target = this.getActiveGroup();
        }

        if (target && target.selectable && !shouldGroup) {
        this._beforeTransform(e, target);
        this._setupCurrentTransform(e, target);
        }
        // we must renderAll so that active image is placed on the top canvas
        shouldRender && this.renderAll();

        this.fire('mouse:down', { target: target, e: e });
        target && target.fire('mousedown', { e: e });
    }
};