allow for override

core/src/components/modal/modal.tsx

@@ -1,6 +1,7 @@
 import { Component, ComponentInterface, Element, Event, EventEmitter, Host, Method, Prop, h } from '@stencil/core';
 
 import { getIonMode } from '../../global/ionic-global';
+import { config } from '../../global/config';
 import { Animation, AnimationBuilder, ComponentProps, ComponentRef, FrameworkDelegate, Gesture, OverlayEventDetail, OverlayInterface } from '../../interface';
 import { attachComponent, detachComponent } from '../../utils/framework-delegate';
 import { BACKDROP, activeAnimations, dismiss, eventMethod, prepareOverlay, present } from '../../utils/overlays';
@@ -150,7 +151,8 @@ export class Modal implements ComponentInterface, OverlayInterface {
       // All of the elements needed for the swipe gesture
       // should be in the DOM and referenced by now, except
       // for the presenting el
-      const ani = this.animation = iosLeaveAnimation(this.el, this.presentingElement);
+      const animationBuilder = (this.leaveAnimation) ? this.leaveAnimation : config.get('modalLeave', iosEnterAnimation);
+      const ani = this.animation = animationBuilder(this.el, this.presentingElement);
       this.gesture = createSwipeToCloseGesture(
         this.el,
         ani,