javascript - Angularjs - 文本区域自动增长

Question

我想用这个directive在我的项目中，但我希望文本区域在加载内容时扩展。

Angular-Autogrow.js:

(function(){
    'use strict';
    angular.module('angular-autogrow', []).directive('autogrow', ['$window', function($window){
        return {
            link: function($scope, $element, $attrs){

                /**
                 * Default settings
                 */
                $scope.attrs = {
                    rows: 1,
                    maxLines: 999
                };

                /**
                 * Merge defaults with user preferences
                 */
                for(var i in $scope.attrs){
                    if($attrs[i]){
                        $scope.attrs[i] = parseInt($attrs[i]);
                    }
                }

                /**
                 * Calculates the vertical padding of the element
                 * @returns {number}
                 */
                $scope.getOffset = function(){
                    var style = $window.getComputedStyle($element[0], null),
                        props = ['paddingTop', 'paddingBottom'],
                        offset = 0;

                    for(var i=0; i<props.length; i++){
                        offset += parseInt(style[props[i]]);
                    }
                    return offset;
                };

                /**
                 * Sets textarea height as exact height of content
                 * @returns {boolean}
                 */
                $scope.autogrowFn = function(){
                    var newHeight = 0, hasGrown = false;
                    if(($element[0].scrollHeight - $scope.offset) > $scope.maxAllowedHeight){
                        $element[0].style.overflowY = 'scroll';
                        newHeight = $scope.maxAllowedHeight;
                    }
                    else {
                        $element[0].style.overflowY = 'hidden';
                        $element[0].style.height = 'auto';
                        newHeight = $element[0].scrollHeight - $scope.offset;
                        hasGrown = true;
                    }
                    $element[0].style.height = newHeight + 'px';
                    return hasGrown;
                };

                $scope.offset = $scope.getOffset();
                $scope.lineHeight = ($element[0].scrollHeight / $scope.attrs.rows) - ($scope.offset / $scope.attrs.rows);
                $scope.maxAllowedHeight = ($scope.lineHeight * $scope.attrs.maxLines) - $scope.offset;

                $element[0].addEventListener('input', $scope.autogrowFn);
                /**
                 * Auto-resize when there's content on page load
                 */
                if($element[0].value != ''){
                    $scope.autogrowFn();
                }
            }
        }
    }]);
})();

我改变:

// $element[0].addEventListener('input', $scope.autogrowFn);

  $element[0].addEventListener('load', $scope.autogrowFn);//<-- I add this line

但是没有成功。如何更改它以便加载内容时文本区域自动展开？

Answer 1

嗨，您必须先使用该指令，然后在 app.js 中包含“angularjs-autogrow”指令，然后检查文本区域是否会根据您的输入自动增长

HTML

<textarea autogrow></textarea>

JS

var app = angular.module('plunker', ["angularjs-autogrow"]);

app.controller('MainCtrl', function($scope) {

});

供引用https://plnkr.co/edit/kj3ikS30cqVIRofTU22X?p=preview