custom ionic page transitions: "slide" and "slide-down"

slide-down.transition.ts

import {Animation} from "ionic-angular/animations/animation";
import {isPresent} from "ionic-angular/util/util";
import {PageTransition} from "ionic-angular/transitions/page-transition";

const DURATION = 500;
const TRANSFORM = "transform";
const MOVED_DOWN = "translateY(100%)";
const NOT_MOVED = "translateY(0)";
const ZINDEX = "z-index";
const OPACITY = "opacity";
const INDEX_FRONT = 101;
const INDEX_BACK = 100;
const OPAQUE = 1;


export class SlideDownTransition extends PageTransition {

    init() {
        super.init();

        const enteringView = this.enteringView;
        const leavingView = this.leavingView;
        const opts = this.opts;

        this.duration(isPresent(opts.duration) ? opts.duration : DURATION);

        const backDirection = (opts.direction === 'back');

        if (enteringView) {
            const enteringContent = new Animation(this.plt, enteringView.pageRef());
            this.add(enteringContent);

            if (backDirection) {
                enteringContent
                    .fromTo(TRANSFORM, MOVED_DOWN, NOT_MOVED, false)
                    .fromTo(OPACITY, OPAQUE, OPAQUE, false)
                    .fromTo(ZINDEX, INDEX_FRONT, INDEX_FRONT, false);
            } else {
                enteringContent
                    .fromTo(TRANSFORM, NOT_MOVED, NOT_MOVED, false)
                    .fromTo(OPACITY, OPAQUE, OPAQUE, false)
                    .fromTo(ZINDEX, INDEX_BACK, INDEX_BACK, false);
            }

        }

        if (leavingView && leavingView.pageRef()) {
            const leavingContent = new Animation(this.plt, leavingView.pageRef());
            this.add(leavingContent);

            if (backDirection) {
                leavingContent
                    .fromTo(TRANSFORM, NOT_MOVED, NOT_MOVED, false)
                    .fromTo(OPACITY, OPAQUE, OPAQUE, false)
                    .fromTo(ZINDEX, INDEX_BACK, INDEX_BACK, false);
            } else {
                leavingContent
                    .fromTo(TRANSFORM, NOT_MOVED, MOVED_DOWN, false)
                    .fromTo(OPACITY, OPAQUE, OPAQUE, false)
                    .fromTo(ZINDEX, INDEX_FRONT, INDEX_FRONT, false)
                    .afterClearStyles([TRANSFORM, OPACITY]);
            }

        }
    }

}

slide.transition.ts

import {Animation, PageTransition} from "ionic-angular";
import {isPresent} from "ionic-angular/util/util";

const DURATION = 500;
const EASING = 'cubic-bezier(0.36,0.66,0.04,1)';
const OPACITY = 'opacity';
const TRANSFORM = 'transform';
const TRANSLATEX = 'translateX';
const CENTER = '0%';
const OFF_OPACITY = 1;


export class SlideTransition extends PageTransition {

    init() {
        super.init();

        const plt = this.plt;
        const OFF_RIGHT = plt.isRTL ? '-100%' : '100%';
        const OFF_LEFT = plt.isRTL ? '100%' : '-100%';
        const enteringView = this.enteringView;
        const leavingView = this.leavingView;
        const opts = this.opts;

        this.duration(isPresent(opts.duration) ? opts.duration : DURATION);
        this.easing(isPresent(opts.easing) ? opts.easing : EASING);

        const backDirection = (opts.direction === 'back');

        if (enteringView) {
            const enteringContent = new Animation(plt, enteringView.pageRef());
            this.add(enteringContent);

            if (backDirection) {
                enteringContent
                    .fromTo(TRANSLATEX, OFF_LEFT, CENTER, true)
                    .fromTo(OPACITY, OFF_OPACITY, OFF_OPACITY, false);

            } else {
                enteringContent
                    .beforeClearStyles([OPACITY])
                    .fromTo(OPACITY, OFF_OPACITY, OFF_OPACITY, false)
                    .fromTo(TRANSLATEX, OFF_RIGHT, CENTER, true);
            }

        }

        if (leavingView && leavingView.pageRef()) {
            const leavingContent = new Animation(plt, leavingView.pageRef());
            this.add(leavingContent);

            if (backDirection) {
                leavingContent
                    .beforeClearStyles([OPACITY])
                    .fromTo(OPACITY, OFF_OPACITY, OFF_OPACITY, false)
                    .fromTo(TRANSLATEX, CENTER, (plt.isRTL ? '-100%' : '100%'));

            } else {
                leavingContent
                    .fromTo(OPACITY, OFF_OPACITY, OFF_OPACITY, false)
                    .fromTo(TRANSLATEX, CENTER, OFF_LEFT)
                    .afterClearStyles([TRANSFORM, OPACITY]);
            }
        }
    }

}

how to use it?

how to use it?

http://entwicklertagebuch.com/blog/2018/02/how-to-implement-custom-page-transitions-in-an-ionic-app/