File : toolbars/baseToolbar/ButtonsHTMLElementTouchEL.js

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/*
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Copyright - 2017 2023 - wwwouaiebe - Contact: https://www.ouaie.be/
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This  program is free software;
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you can redistribute it and/or modify it under the terms of the
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GNU General Public License as published by the Free Software Foundation;
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either version 3 of the License, or any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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*/
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/*
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Changes:
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    - v4.0.0:
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        - created from v3.6.0
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Doc reviewed 202208
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 */
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import { ZERO, ONE } from '../../main/Constants.js';
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/* ------------------------------------------------------------------------------------------------------------------------- */
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/**
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Touch event listener for the buttons container
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*/
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/* ------------------------------------------------------------------------------------------------------------------------- */
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class ButtonsHTMLElementTouchEL {
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    /**
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    The Y position of the previous touch event
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    @type {Number}
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    */
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    #touchContainerStartY;
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    /**
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    The constructor
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    */
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    constructor ( ) {
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        Object.freeze ( this );
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        this.#touchContainerStartY = Number.MAX_VALUE;
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    }
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    /**
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    Event listener method
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    @param {Event} touchEvent The event to handle
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    */
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    handleEvent ( touchEvent ) {
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        switch ( touchEvent.type ) {
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        case 'touchstart' :
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            if ( ONE === touchEvent.changedTouches.length ) {
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                const touch = touchEvent.changedTouches.item ( ZERO );
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                this.#touchContainerStartY = touch.screenY;
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            }
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            break;
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        case 'touchmove' :
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        case 'touchend' :
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            if ( ONE === touchEvent.changedTouches.length ) {
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                const touch = touchEvent.changedTouches.item ( ZERO );
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                const deltaY = this.#touchContainerStartY - touch.screenY;
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                touchEvent.currentTarget.scrollTop += deltaY;
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                this.#touchContainerStartY = touch.screenY;
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            }
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            break;
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        default :
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            this.#touchContainerStartY = Number.MAX_VALUE;
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            break;
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        }
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        if ( 'touchend' === touchEvent.type ) {
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            this.#touchContainerStartY = Number.MAX_VALUE;
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        }
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    }
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}
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export default ButtonsHTMLElementTouchEL;
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/* --- End of file --------------------------------------------------------------------------------------------------------- */
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