我正在尝试创建自定义<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<%@ Page Language="C#" %>
<%@ Register tagprefix="SharePoint" namespace="Microsoft.SharePoint.WebControls" assembly="Microsoft.SharePoint, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<html dir="ltr" xmlns="http://www.w3.org/1999/xhtml" xmlns:mso="urn:schemas-microsoft-com:office:office" xmlns:msdt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882">
<head runat="server">
<meta name="WebPartPageExpansion" content="full" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>jquery validate</title>
<meta http-equiv="X-UA-Compatible" content="IE=10" />
<SharePoint:CssRegistration Name="default" runat="server"/>
<!--[if gte mso 9]>
<SharePoint:CTFieldRefs runat=server Prefix="mso:" FieldList="FileLeafRef,WikiField,_dlc_DocId,_dlc_DocIdUrl,_dlc_DocIdPersistId"><xml>
<mso:CustomDocumentProperties>
<mso:_dlc_DocId msdt:dt="string">5JSTYM4NXMKN-1550736763-50</mso:_dlc_DocId>
<mso:_dlc_DocIdItemGuid msdt:dt="string">56166d47-3111-4d9e-86c4-34fc0308c55f</mso:_dlc_DocIdItemGuid>
<mso:_dlc_DocIdUrl msdt:dt="string">http://sp2013/sites/team/_layouts/15/DocIdRedir.aspx?ID=5JSTYM4NXMKN-1550736763-50, 5JSTYM4NXMKN-1550736763-50</mso:_dlc_DocIdUrl>
</mso:CustomDocumentProperties>
</xml></SharePoint:CTFieldRefs><![endif]-->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css"/>
<script src="https://code.jquery.com/jquery-1.12.4.min.js" type="text/javascript"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery-validate/1.17.0/jquery.validate.min.js"></script>
<script type="text/javascript">
$(function(){
$.validator.setDefaults({
submitHandler: function () {
alert( "Submitted!" );
}
});
$("#signupForm1").validate( {
rules: {
ACI_client_name_input: "required"
},
messages: {
ACI_client_name_input: "Please enter the Client name",
},
/* THIS PART WAS PUT IN FROM GUIDE ONLINE FOR SHAREPOINT SITES */
//if ($("input[title='ACI_client-name-input']").attr("name") == undefined) {
// $("input[title='ACI_client-name-input']").attr("name", $("input[title='ACI_client-name-input']").attr("id"));
//}
errorElement: "em",
errorPlacement: function ( error, element ) {
// Add the `help-block` class to the error element
error.addClass( "help-block" );
// Add `has-feedback` class to the parent div.form-group
// in order to add icons to inputs
element.parents( ".col-sm-5" ).addClass( "has-feedback" );
if ( element.prop( "type" ) === "checkbox" ) {
error.insertAfter( element.parent( "label" ) );
} else {
error.insertAfter( element );
}
// Add the span element, if doesn't exists, and apply the icon classes to it.
if ( !element.next( "span" )[ 0 ] ) {
$( "<span class='glyphicon glyphicon-remove form-control-feedback'></span>" ).insertAfter( element );
}
},
success: function ( label, element ) {
// Add the span element, if doesn't exists, and apply the icon classes to it.
if ( !$( element ).next( "span" )[ 0 ] ) {
$( "<span class='glyphicon glyphicon-ok form-control-feedback'></span>" ).insertAfter( $( element ) );
}
},
highlight: function ( element, errorClass, validClass ) {
$( element ).parents( ".col-sm-5" ).addClass( "has-error" ).removeClass( "has-success" );
$( element ).next( "span" ).addClass( "glyphicon-remove" ).removeClass( "glyphicon-ok" );
},
unhighlight: function ( element, errorClass, validClass ) {
$( element ).parents( ".col-sm-5" ).addClass( "has-success" ).removeClass( "has-error" );
$( element ).next( "span" ).addClass( "glyphicon-ok" ).removeClass( "glyphicon-remove" );
}
});
});
</script>
</head>
<body>
<form id="signupForm1" method="post" class="form-horizontal" action novalidate="novalidate">
<div class="form-group row" style="margin-bottom: 15px;">
<label class="col-lg-10 control-label" for="ACI_client-name-input">Client Name</label>
<div class="col-lg-8 required-after">
<input type="text" class="form-control" id="ACI_client_name_input" name="ACI_client_name_input" placeholder="Ex: FleishmanHillard" required/>
<span class="">*</span>
</div>
</div>
<div class="form-group row col-lg-8">
<button type="submit" name="singlebutton" class="btn btn-success" id="submit">Submit</button>
<button type="reset" name="cancelbutton" class="btn btn-warning" id="cancel" onclick="window.location.href='//fh126cloud.sharepoint.com/emplsrv/missupport/pages/MailChimpIntake.aspx'">Cancel</button>
</div>
</form>
</body>
</html>
。
首先，我只想旋转附加到RecyclerView的列表的第一个元素。
以下是我尝试通过覆盖recyclerView方法做的事情：
setAdapter但每次我尝试更改列表中的元素时都会收到此错误：
引起：java.lang.NullPointerException：尝试在空对象引用上调用虚方法'void android.view.View.setRotation（float）'
我希望逐个获取这个RecyclerView项目来修改它们。是否可以到达我的RecyclerView的每个项目以添加它们的修改？知道我实际上正在创建自定义视图扩展RecyclerView 而不是 RecyclerView适配器。
答案 0 :(得分：1)
应用崩溃是因为您尝试访问不存在的视图。当您调用setAdapter时，它只会创建适配器对象并将其设置为RecyclerView。那时孩子还没有被创建，所以getChildAt(0)返回null并且你得到了崩溃。
相反，您应该使用适配器进行项目视图操作。在您的适配器中覆盖onBindViewHolder方法并在那里执行。每次将项目视图绑定到RecyclerView时，都会调用该方法。它有一个位置参数，可用于仅旋转列表中的第一个项目。