Retain checkbox selection on click of previous and

2019-08-19 09:00发布

问题:

I've a bootstrap modal which contains a table of users. I can select a user from the table and on clicking 'save', the details of seleced user is displayed. I'm displaying 10 users per page in the table of the modal. However, if I select any user from page 1 and then click next to select some users from page 2 and click on 'save', my selection from page 1 is not retained.

I mean the checkbox is cleared on page 1, whenever I click on next or previous. How do I retain this selection on my checkbox, even if I click on next or previous at any page?

Here's the snippet:

var currentPageNo = 0; // Keep track of currently displayed page


// Select button that is descendant of userList
$('#userList .prev-btn').click(function(){ 
    userList(currentPageNo-10);
});
$('#userList .next-btn').click(function(){ 
    userList(currentPageNo+10);
});
$('#adminList .prev-btn').click(function(){ 
    adminList(currentPageNo-10);
});
$('#adminList .next-btn').click(function(){ 
    adminList(currentPageNo+10);
});

function userList(pageNo) {
    var resType="userList";
    createTable(resType,pageNo);
}

function adminList(pageNo) {
    var resType="adminList";
    createTable(resType,pageNo);
}

function createTable(resType, pageNo) {
    // Update global variable
    currentPageNo = pageNo; 
    // Set visibility of the correct "prev" button:
    $('#' + resType + ' .prev-btn').toggle(pageNo > 0);
    // Ask one record more than needed, to determine if there are more records after this page:
    $.getJSON("https://api.randomuser.me/?results=11&resType="+resType + "&pageIndex=" + pageNo, function(data) {
        var $table = $('#' + resType + ' table');
        $('tr:has(td)', $table).empty();
        // Check if there's an extra record which we do not display, 
        // but determines that there is a next page
        $('#' + resType + ' .next-btn').toggle(data.results.length > 10);
        // Slice results, so 11th record is not included:
        data.results.slice(0, 10).forEach(function (record, i) { // add second argument for numbering records
            var json = JSON.stringify(record);
            $table.append(
                $('<tr>').append(
                    $('<td>').append(
                        $('<input>').attr('type', 'checkbox')
                                    .addClass('selectRow')
                                    .val(json),
                        (i+1+pageNo) // display row number
                    ),
                    $('<td>').append(
                        $('<a>').attr('href', record.picture.thumbnail)
                                .addClass('imgurl')
                                .attr('target', '_blank')
                                .text(record.name.first)
                    ),
                    $('<td>').append(record.dob)
                )
            );
        });
        // Show the prev and/or buttons
        
        
    }).fail(function(error) {
        console.log("**********AJAX ERROR: " + error);
    });            
}

var savedData = []; // The objects as array, so to have an order.

function saveData(){
    var errors = [];
    // Add selected to map
    $('input.selectRow:checked').each(function(count) {
        // Get the JSON that is stored as value for the checkbox
        var obj = JSON.parse($(this).val());
        // See if this URL was already collected (that's easy with Set)
        if (savedData.find(record => record.picture.thumbnail === obj.picture.thumbnail)) {
            errors.push(obj.name.first);
        } else {
            // Append it
            savedData.push(obj);
        }
    });
    refreshDisplay();
    if (errors.length) {
        alert('The following were already selected:\n' + errors.join('\n'));
    }
}

function refreshDisplay() {
    $('.container').html('');
    savedData.forEach(function (obj) {
        // Reset container, and append collected data (use jQuery for appending)
        $('.container').append(
            $('<div>').addClass('parent').append(
                $('<label>').addClass('dataLabel').text('Name: '),
                obj.name.first + ' ' + obj.name.last,
                $('<br>'), // line-break between name & pic
                $('<img>').addClass('myLink').attr('src', obj.picture.thumbnail), $('<br>'),
                $('<label>').addClass('dataLabel').text('Date of birth: '),
                obj.dob, $('<br>'),
                $('<label>').addClass('dataLabel').text('Address: '), $('<br>'),
                obj.location.street, $('<br>'),
                obj.location.city + ' ' + obj.location.postcode, $('<br>'),
                obj.location.state, $('<br>'),
                $('<button>').addClass('removeMe').text('Delete'),
                $('<button>').addClass('top-btn').text('Swap with top'),
                $('<button>').addClass('down-btn').text('Swap with down')
            )	
        );
    })
    // Clear checkboxes:
    $('.selectRow').prop('checked', false);
    handleEvents();
}

function logSavedData(){
    // Convert to JSON and log to console. You would instead post it
    // to some URL, or save it to localStorage.
    console.log(JSON.stringify(savedData, null, 2));
}

function getIndex(elem) {
    return $(elem).parent('.parent').index();
}

$(document).on('click', '.removeMe', function() {
    // Delete this from the saved Data
    savedData.splice(getIndex(this), 1);
    // And redisplay
    refreshDisplay();
});

/* Swapping the displayed articles in the result list */
$(document).on('click', ".down-btn", function() {
    var index = getIndex(this);
    // Swap in memory
    savedData.splice(index, 2, savedData[index+1], savedData[index]);
    // And redisplay
    refreshDisplay();
});

$(document).on('click', ".top-btn", function() {
    var index = getIndex(this);
    // Swap in memory
    savedData.splice(index-1, 2, savedData[index], savedData[index-1]);
    // And redisplay
    refreshDisplay();
});
    
/* Disable top & down buttons for the first and the last article respectively in the result list */
function handleEvents() {
    $(".top-btn, .down-btn").prop("disabled", false).show();
    $(".parent:first").find(".top-btn").prop("disabled", true).hide();
    $(".parent:last").find(".down-btn").prop("disabled", true).hide();
}

$(document).ready(function(){
    $('#showExtForm-btn').click(function(){
        $('#extUser').toggle();
    });
    $("#extUserForm").submit(function(e){
        addExtUser();
        return false;
   });
});

function addExtUser() {
    var extObj = {
        name: {
            title: "mr", // No ladies? :-)
            first: $("#name").val(),
            // Last name ?
        },
        dob: $("#dob").val(),
        picture: {
            thumbnail: $("#myImg").val()
        },
        location: { // maybe also ask for this info?
        }
    };
    savedData.push(extObj);
    refreshDisplay(); // Will show some undefined stuff (location...)
}
.parent {
	background-color: #0000FF;
	color: white;
	border: 1px solid black;
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#userList" onclick="userList(0)">User List</button>
<button class="btn btn-primary btn-sm" onclick="logSavedData()">Get Saved Data</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#adminList" onclick="adminList(0)">User Admin</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#extUser">Open External Form</button>

  <div class="modal fade" id="userList" role="dialog">
    <div class="modal-dialog modal-lg">
    
      
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">User List</h4>
        </div>
        <div class="modal-body">
          <div class="table-responsive">
              <table class="table table-bordered table-hover" id="datatable">
                <tr>
                    <th>Select</th>
                    <th>Name</th>
                    <th>DOB</th>
                </tr>
            </table>
          </div>
          <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
            </div>

            <div class="col-sm-4">
                <button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
            </div>
        </div>
            <hr/>
        <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
            </div>
            <div class="col-sm-4">
                <button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
            </div>
        </div>
        <br />
      </div>
    </div>
  </div>
</div>

<div class="modal fade" id="adminList" role="dialog">
    <div class="modal-dialog modal-lg">
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Admin List</h4>
        </div>
        <div class="modal-body">
          <div class="table-responsive">
              <table class="table table-bordered table-hover" id="datatable">
                <tr>
                    <th>Select</th>
                    <th>Name</th>
                    <th>DOB</th>
                </tr>
            </table>
          </div>
          <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
            </div>

            <div class="col-sm-4">
                <button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
            </div>
        </div>
            <hr/>
        <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
            </div>
            <div class="col-sm-4">
                <button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
            </div>
        </div>
        <br />
      </div>
    </div>
  </div>
</div>

<div class="modal fade" id="extUser" role="dialog">
    <div class="modal-dialog modal-lg">
    
      <!-- External User-->
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Add External User</h4>
        </div>
        <div class="modal-body">
          <form class="form-horizontal" id="extUserForm">
            <div class="form-group">
              <label class="control-label col-sm-3" for="name">Name:</label>
              <div class="col-sm-8">
                <input type="text" class="form-control" id="name" name="name" required>
              </div>
            </div>
            <div class="form-group">
              <label class="control-label col-sm-3" for="myImg">Image:</label>
              <div class="col-sm-8">
                <input type="text" class="form-control" id="myImg" name="myImg" required>
              </div>
            </div>
                                            
            <div class="form-group">
              <label class="control-label col-sm-3" for="dob">DOB:</label>
              <div class="col-sm-8">
                <input type="date" class="form-control" id="dob" name="dob" required>
              </div>
            </div>
            <hr />
            <div class="form-group">        
              <div class="col-sm-offset-3 col-sm-3">
                <button class="btn btn-primary btn-sm">Submit</button>
              </div>
              <div class="col-sm-3">
                <button type="reset" class="btn btn-primary btn-sm">Reset</button>
              </div>
              <div class="col-sm-3">
                <button type="button" class="btn btn-primary btn-sm close-external-modal" data-dismiss="modal">Close</button>
              </div>
            </div>
          </form>
        </div> 
      </div>
    </div>
  </div>

<div class="container"></div>

回答1:

If you want the checkboxes to persist even when you move to another page, I would suggest that you actually keep those rows with checkboxes, but just hide them when moving to the next page.

The idea is that you never remove rows, but only add them when moving to a page you had not yet visited. But when going back to previous pages, you just make those 10 rows visible, and hide all others. That way you will even have a better user-experience, since those pages do not have to be requested from the server any more.

To achieve this, you just have to make a few changes in the first few lines of the creatTable function:

function createTable(resType, pageNo) {
    // Update global variable
    currentPageNo = pageNo; 
    // Set visibility of the correct "prev" button:
    $('#' + resType + ' .prev-btn').toggle(pageNo > 0);
    // *** See if we have that page already loaded
    var $table = $('#' + resType + ' table');
    // *** Count the rows already in the table, to see if we already have the page
    var lastPageNo = $('tr:has(td)', $table).length - 1;
    if (currentPageNo < lastPageNo) {
        // *** We have the page: hide all rows, except those of that page
        $('tr:has(td)', $table).hide().slice(currentPageNo, currentPageNo+10).show();
        return;
    }
    // Otherwise make the request.
    // Ask one record more than needed, to determine if there are more records after this page:
    $.getJSON("https://api.randomuser.me/?results=11&resType="+resType + "&pageIndex=" + pageNo, function(data) {
        //*** don't clear the table, but hide all rows, so they can be reused when paging back
        $('tr:has(td)', $table).hide();
        // Check if there's an extra record which we do not display, 
        // but determines that there is a next page
        $('#' + resType + ' .next-btn').toggle(data.results.length > 10);
        // ...etc ... etc

Here is the whole snippet:

var currentPageNo = 0; // Keep track of currently displayed page

// Select button that is descendant of userList
$('#userList .prev-btn').click(function(){ 
    userList(currentPageNo-10);
});
$('#userList .next-btn').click(function(){ 
    userList(currentPageNo+10);
});
$('#adminList .prev-btn').click(function(){ 
    adminList(currentPageNo-10);
});
$('#adminList .next-btn').click(function(){ 
    adminList(currentPageNo+10);
});

function userList(pageNo) {
    var resType="userList";
    createTable(resType,pageNo);
}

function adminList(pageNo) {
    var resType="adminList";
    createTable(resType,pageNo);
}

function createTable(resType, pageNo) {
    // Update global variable
    currentPageNo = pageNo; 
    // Set visibility of the correct "prev" button:
    $('#' + resType + ' .prev-btn').toggle(pageNo > 0);
    // *** See if we have that page already loaded
    var $table = $('#' + resType + ' table');
    // *** Count the rows already in the table, to see if we already have the page
    var lastPageNo = $('tr:has(td)', $table).length - 1;
    if (currentPageNo < lastPageNo) {
        // *** We have the page: hide all rows, except those of that page
        $('tr:has(td)', $table).hide().slice(currentPageNo, currentPageNo+10).show();
        return;
    }
    // Otherwise make the request.
    // Ask one record more than needed, to determine if there are more records after this page:
    $.getJSON("https://api.randomuser.me/?results=11&resType="+resType + "&pageIndex=" + pageNo, function(data) {
        //*** don't clear the table, but hide all rows, so they can be reused when paging back
        $('tr:has(td)', $table).hide();
        // Check if there's an extra record which we do not display, 
        // but determines that there is a next page
        $('#' + resType + ' .next-btn').toggle(data.results.length > 10);
        // Slice results, so 11th record is not included:
        data.results.slice(0, 10).forEach(function (record, i) { // add second argument for numbering records
            var json = JSON.stringify(record);
            $table.append(
                $('<tr>').append(
                    $('<td>').append(
                        $('<input>').attr('type', 'checkbox')
                                    .addClass('selectRow')
                                    .val(json),
                        (i+1+pageNo) // display row number
                    ),
                    $('<td>').append(
                        $('<a>').attr('href', record.picture.thumbnail)
                                .addClass('imgurl')
                                .attr('target', '_blank')
                                .text(record.name.first)
                    ),
                    $('<td>').append(record.dob)
                )
            );
        });
    }).fail(function(error) {
        console.log("**********AJAX ERROR: " + error);
    });            
}

var savedData = []; // The objects as array, so to have an order.

function saveData(){
    var errors = [];
    // Add selected to map
    $('input.selectRow:checked').each(function(count) {
        // Get the JSON that is stored as value for the checkbox
        var obj = JSON.parse($(this).val());
        // See if this URL was already collected (that's easy with Set)
        if (savedData.find(record => record.picture.thumbnail === obj.picture.thumbnail)) {
            errors.push(obj.name.first);
        } else {
            // Append it
            savedData.push(obj);
        }
    });
    refreshDisplay();
    if (errors.length) {
        alert('The following were already selected:\n' + errors.join('\n'));
    }
}

function refreshDisplay() {
    $('.container').html('');
    savedData.forEach(function (obj) {
        // Reset container, and append collected data (use jQuery for appending)
        $('.container').append(
            $('<div>').addClass('parent').append(
                $('<label>').addClass('dataLabel').text('Name: '),
                obj.name.first + ' ' + obj.name.last,
                $('<br>'), // line-break between name & pic
                $('<img>').addClass('myLink').attr('src', obj.picture.thumbnail), $('<br>'),
                $('<label>').addClass('dataLabel').text('Date of birth: '),
                obj.dob, $('<br>'),
                $('<label>').addClass('dataLabel').text('Address: '), $('<br>'),
                obj.location.street, $('<br>'),
                obj.location.city + ' ' + obj.location.postcode, $('<br>'),
                obj.location.state, $('<br>'),
                $('<button>').addClass('removeMe').text('Delete'),
                $('<button>').addClass('top-btn').text('Swap with top'),
                $('<button>').addClass('down-btn').text('Swap with down')
            )	
        );
    })
    // Clear checkboxes:
    $('.selectRow').prop('checked', false);
    handleEvents();
}

function logSavedData(){
    // Convert to JSON and log to console. You would instead post it
    // to some URL, or save it to localStorage.
    console.log(JSON.stringify(savedData, null, 2));
}

function getIndex(elem) {
    return $(elem).parent('.parent').index();
}

$(document).on('click', '.removeMe', function() {
    // Delete this from the saved Data
    savedData.splice(getIndex(this), 1);
    // And redisplay
    refreshDisplay();
});

/* Swapping the displayed articles in the result list */
$(document).on('click', ".down-btn", function() {
    var index = getIndex(this);
    // Swap in memory
    savedData.splice(index, 2, savedData[index+1], savedData[index]);
    // And redisplay
    refreshDisplay();
});

$(document).on('click', ".top-btn", function() {
    var index = getIndex(this);
    // Swap in memory
    savedData.splice(index-1, 2, savedData[index], savedData[index-1]);
    // And redisplay
    refreshDisplay();
});
    
/* Disable top & down buttons for the first and the last article respectively in the result list */
function handleEvents() {
    $(".top-btn, .down-btn").prop("disabled", false).show();
    $(".parent:first").find(".top-btn").prop("disabled", true).hide();
    $(".parent:last").find(".down-btn").prop("disabled", true).hide();
}

$(document).ready(function(){
    $('#showExtForm-btn').click(function(){
        $('#extUser').toggle();
    });
    $("#extUserForm").submit(function(e){
        addExtUser();
        return false;
   });
});

function addExtUser() {
    var extObj = {
        name: {
            title: "mr", // No ladies? :-)
            first: $("#name").val(),
            // Last name ?
        },
        dob: $("#dob").val(),
        picture: {
            thumbnail: $("#myImg").val()
        },
        location: { // maybe also ask for this info?
        }
    };
    savedData.push(extObj);
    refreshDisplay(); // Will show some undefined stuff (location...)
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#userList" onclick="userList(0)">User List</button>
<button class="btn btn-primary btn-sm" onclick="logSavedData()">Get Saved Data</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#adminList" onclick="adminList(0)">User Admin</button>
<button class="btn btn-primary btn-sm" data-toggle="modal" data-target="#extUser">Open External Form</button>

  <div class="modal fade" id="userList" role="dialog">
    <div class="modal-dialog modal-lg">
    
      
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">User List</h4>
        </div>
        <div class="modal-body">
          <div class="table-responsive">
              <table class="table table-bordered table-hover" id="datatable">
                <tr>
                    <th>Select</th>
                    <th>Name</th>
                    <th>DOB</th>
                </tr>
            </table>
          </div>
          <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
            </div>

            <div class="col-sm-4">
                <button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
            </div>
        </div>
            <hr/>
        <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
            </div>
            <div class="col-sm-4">
                <button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
            </div>
        </div>
        <br />
      </div>
    </div>
  </div>
</div>

<div class="modal fade" id="adminList" role="dialog">
    <div class="modal-dialog modal-lg">
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Admin List</h4>
        </div>
        <div class="modal-body">
          <div class="table-responsive">
              <table class="table table-bordered table-hover" id="datatable">
                <tr>
                    <th>Select</th>
                    <th>Name</th>
                    <th>DOB</th>
                </tr>
            </table>
          </div>
          <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary prev-btn"><span class="glyphicon glyphicon-chevron-left"></span></button>
            </div>

            <div class="col-sm-4">
                <button type="button" class="btn btn-primary next-btn"><span class="glyphicon glyphicon-chevron-right"></span></button>
            </div>
        </div>
            <hr/>
        <div class="row">
            <div class="col-sm-offset-3 col-sm-4">
                <button type="button" class="btn btn-primary btn-sm" onclick="saveData()">Save selected</button>
            </div>
            <div class="col-sm-4">
                <button type="button" class="btn btn-primary btn-sm close-less-modal" data-dismiss="modal">Close</button>
            </div>
        </div>
        <br />
      </div>
    </div>
  </div>
</div>

<div class="modal fade" id="extUser" role="dialog">
    <div class="modal-dialog modal-lg">
    
      <!-- External User-->
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Add External User</h4>
        </div>
        <div class="modal-body">
          <form class="form-horizontal" id="extUserForm">
            <div class="form-group">
              <label class="control-label col-sm-3" for="name">Name:</label>
              <div class="col-sm-8">
                <input type="text" class="form-control" id="name" name="name" required>
              </div>
            </div>
            <div class="form-group">
              <label class="control-label col-sm-3" for="myImg">Image:</label>
              <div class="col-sm-8">
                <input type="text" class="form-control" id="myImg" name="myImg" required>
              </div>
            </div>
                                            
            <div class="form-group">
              <label class="control-label col-sm-3" for="dob">DOB:</label>
              <div class="col-sm-8">
                <input type="date" class="form-control" id="dob" name="dob" required>
              </div>
            </div>
            <hr />
            <div class="form-group">        
              <div class="col-sm-offset-3 col-sm-3">
                <button class="btn btn-primary btn-sm">Submit</button>
              </div>
              <div class="col-sm-3">
                <button type="reset" class="btn btn-primary btn-sm">Reset</button>
              </div>
              <div class="col-sm-3">
                <button type="button" class="btn btn-primary btn-sm close-external-modal" data-dismiss="modal">Close</button>
              </div>
            </div>
          </form>
        </div> 
      </div>
    </div>
  </div>

<div class="container"></div>