angular其实不再需要input和textarea标签来做输入功能，只需要给div加个h5属性contenteditable="true"即可使用ng-model实现双向绑定，和高度自适应的功能，
苹果手机不支持h5属性 contenteditable="true"，需要在这个div中添加样式-webkit-user-select:text
这里的ng-model只能绑定对象中的某一个元素，如ng-model=“content.item”
div{
-webkit-user-select:text;
}
/*为空时显示 element attribute content*/
div
:empty:before{
content: attr(placeholder); /* element attribute*/
color:#red; /*content: 'this is content';*/
}
/*焦点时内容为空*/
div
:focus:before{
content:none;
}
html代码
<div contenteditable="true" class="texttitle zkht-create-answer" ng-model="content.item"></div>
directive.js
app.directive('contenteditable', function() {
return {
restrict: 'A', // 只用于属性
require: '?ngModel', // get a hold of NgModelController
link: function(scope, element, attrs, ngModel) {
if (!ngModel) {
return;
}
// Specify how UI should be updated
ngModel.$render = function() {
element.html(ngModel.$viewValue || '');
};
// Listen for change events to enable binding
element.on('blur keyup change', function() {
scope.$apply(readViewText);
});
// No need to initialize, AngularJS will initialize the text based on ng-model attribute
// Write data to the model
function readViewText() {
var html = element.html();
// When we clear the content editable the browser leaves a <br> behind
// If strip-br attribute is provided then we strip this out
if (attrs.stripBr && html === '<br>') {
html = '';
}
ngModel.$setViewValue(html);
}
}
};