Dynamically Change the Color of the Stepper Steps
Environment
| Product Version | 2022.3.913 |
| Product | Telerik UI for ASP.NET Core Stepper |
Description
How can I dynamically change the color of the Stepper steps?
Solution
This example demonstrates how to validate or save each step and change its color dynamically based on the following requirements:
- If a specified step is validated successfully, its icon is colored in green.
- If the step validation fails, its icon is colored in red.
- If the step is saved, its icon is colored in blue.
- When selecting the next step, the previous step is colored in yellow if it has not been validated or saved.
The scenario relies on the following key steps:
- Create a "Validate step" button and handle its
clickevent. In theclickevent handler:- Get the currently active step by using the
select()method of the Stepper. - Validate the step's content and store the step-index in a global array
validatedSteps. - If the validation succeeds, add class "correct" to the step HTML element. Otherwise, add class "errors-step".
- Get the currently active step by using the
- Create a "Save step" button and handle its
clickevent. In theclickevent handler:- Get the currently active step and store its index in a global array
savedSteps. - Add class "save" to the step HTML element.
- Get the currently active step and store its index in a global array
- Create a Stepper and handle its
Selectevent. In the event handler:- Iterate through the
validatedSteps/savedStepsarrays and persist the added class of each step. - Add class "pending" to the steps that are not validated or saved.
- Iterate through the
- Set the respective CSS attributes (
background-colorandborder-color) to the classes "errors-step", "correct", "pending", and "save".
@(Html.Kendo().Button()
.Name("validateStep")
.Content("Validate step")
.Events(ev => ev.Click("onValidateStep"))
)
@(Html.Kendo().Button()
.Name("saveStep")
.Content("Save step")
.Events(ev => ev.Click("onSaveStep"))
)
@(Html.Kendo().Stepper()
.Name("stepper")
.Steps(s =>
{
s.Add().Label("First step");
s.Add().Label("Second step");
s.Add().Label("Third step");
s.Add().Label("Last step");
})
.Events(events => events.Select("onSelect"))
)
<br /><br />
//A Form, which groups are displayed per step
@(Html.Kendo().Form<FormOrderViewModel>()
.Name("exampleForm")
.HtmlAttributes(new { action = "Groups", method = "POST" })
.Items(items =>
{
items.AddGroup() //Visible on Step 1
.Label("Personal Information")
.Layout("grid")
.Items(i =>
{
i.Add()
.Field(f => f.FirstName)
.Label(l => l.Text("First Name:"));
i.Add()
.Field(f => f.LastName)
.Label(l => l.Text("Last Name:"));
});
items.AddGroup() //Visible on Step 2
.Label("Shipping Country")
.Layout("grid")
.Items(i =>
{
i.Add()
.Field(f => f.ShipCountry)
.Label(l => l.Text("Country:"))
.Editor(e =>
{
e.ComboBox()
.DataTextField("Text")
.DataValueField("Value")
.BindTo(new List<SelectListItem>() {
new SelectListItem() {
Text = "France", Value = "1"
},
new SelectListItem() {
Text = "Germany", Value = "2"
},
new SelectListItem() {
Text = "Italy", Value = "3"
},
new SelectListItem() {
Text = "Spain", Value = "4"
}
});
});
i.Add()
.Field(f => f.City)
.Label(l => l.Text("City:"));
});
items.AddGroup() //Visible on Step 3
.Label("Shipping Address")
.Layout("grid")
.Items(i =>
{
i.Add()
.Field(f => f.Address)
.Label(l => l.Text("Address Line:"));
});
})
)
<div class="last-step-content">Successfully completed form!</div> //Visible on Step 4
<script>
var validatedSteps = [];
var savedSteps = [];
$(document).ready(function () {
$("#exampleForm .k-form-fieldset:nth-child(2)").hide();
$("#exampleForm .k-form-fieldset:nth-child(3)").hide();
$(".last-step-content").hide();
$("#exampleForm .k-form-buttons .k-form-submit").hide();
});
function onSaveStep(e) { //"Button "Save step" click event handler
var stepper = $("#stepper").getKendoStepper();
var currentActiveStep = stepper.select(); //Get the currently active step
saveStep(currentActiveStep.options.index, savedSteps, currentActiveStep.element, validatedSteps);
}
function saveStep(stepIndex, savedSteps, stepElement, validatedSteps) { //Save the step and apply the respective class
$(stepElement).removeClass("pending").removeClass("errors-step").removeClass("correct");
//Store the saved step
var isAlreadySaved = $.grep(savedSteps, function (e) { return e.index == stepIndex; });
if (isAlreadySaved.length == 0) {
savedSteps.push({ index: stepIndex, saved: true });
}
//Remove the Saved step from the validated steps
var isValidated = $.grep(validatedSteps, function (e) { return e.index == stepIndex; });
if (isValidated.length > 0) {
for (var i = 0; i < validatedSteps.length; i++) {
if (validatedSteps[i].index == stepIndex) {
validatedSteps.splice(i, 1);
break;
}
}
}
$(stepElement).addClass("save"); //Add class "save" to apply the blue color
}
function onValidateStep() { //"Button "Validate step" click event handler
var stepper = $("#stepper").getKendoStepper();
var currentActiveStep = stepper.select(); //Get the currently active step
if (currentActiveStep.options.index == 0) {
//Validatiing Step 1
checkStepValidation(currentActiveStep.options.index, validatedSteps, currentActiveStep.element, $("#FirstName").val() == "");
} else if (currentActiveStep.options.index == 1) {
//Validatiing Step 2
checkStepValidation(currentActiveStep.options.index, validatedSteps, currentActiveStep.element, $("#City").val() == "");
} else if (currentActiveStep.options.index == 2) {
//Validatiing Step 3
checkStepValidation(currentActiveStep.options.index, validatedSteps, currentActiveStep.element, $("#Address").val() == "");
}
}
function checkStepValidation(stepIndex, validatedSteps, validatedStepElement, validationCondition) { //Validate the step and apply the respective class
$(validatedStepElement).removeClass("errors-step").removeClass("correct").removeClass("save"); //Reset the step classes
var existingValidation = $.grep(validatedSteps, function (e) { return e.index == stepIndex; }); //Store the validated step
if (existingValidation.length == 0) {
validatedSteps.push({ index: stepIndex, errors: validationCondition });
} else {
for (var i in validatedSteps) {
if (validatedSteps[i].index == stepIndex) {
validatedSteps[i].errors = validationCondition;
break;
}
}
}
if (validationCondition) { //if returns true (the validation is NOT successfull) Apply the respective class/color
$(validatedStepElement).addClass("errors-step");
} else $(validatedStepElement).addClass("correct");
var isSaved = $.grep(savedSteps, function (e) { return e.index == stepIndex; }); //Check if the step has been saved before the validation and remove it fromthe saved steps
if (isSaved.length > 0) {
for (var i = 0; i < savedSteps.length; i++) {
if (savedSteps[i].index == stepIndex) {
savedSteps.splice(i, 1);
break;
}
}
}
}
function onSelect(e) { //Stepper "Select" event handler
var steps = e.sender.steps();
setTimeout(function () {
//Persist Validated Steps
if (validatedSteps.length > 0) {
$.each(validatedSteps, function (i, stepData) {
$(steps[stepData.index].element).removeClass("pending");
if (stepData.errors) {
$(steps[stepData.index].element).addClass("errors-step");
} else {
$(steps[stepData.index].element).addClass("correct");
}
});
}
//Persist Saved Steps
if (savedSteps.length > 0) {
$.each(savedSteps, function (i, stepData) {
$(steps[stepData.index].element).removeClass("pending");
$(steps[stepData.index].element).addClass("save");
});
}
//Persist Moved Steps
$.each(steps, function () {
var element = $(this.element);
if (!$(element).hasClass('correct') && !$(element).hasClass('errors-step') && !$(element).hasClass('save') && $(element).hasClass('k-step-done')) {
$(element).addClass("pending");
}
});
}, 10);
//Display the respective content when a step is selected
if (e.step.options.label == "Second step") {
$("#exampleForm .k-form-fieldset:first").hide();
$("#exampleForm .k-form-fieldset:nth-child(2)").show();
$("#exampleForm .k-form-fieldset:nth-child(3)").hide();
$("#exampleForm .k-form-buttons .k-form-submit").hide();
$("#exampleForm .k-form-buttons .k-form-clear").show();
$(".last-step-content").hide();
} else if (e.step.options.label == "Third step") {
$("#exampleForm .k-form-fieldset:first").hide();
$("#exampleForm .k-form-fieldset:nth-child(2)").hide();
$("#exampleForm .k-form-fieldset:nth-child(3)").show();
$("#exampleForm .k-form-buttons .k-form-submit").show();
$("#exampleForm .k-form-buttons .k-form-clear").show();
$(".last-step-content").hide();
} else if (e.step.options.label == "Last step") {
$("#exampleForm .k-form-fieldset:first").hide();
$("#exampleForm .k-form-fieldset:nth-child(2)").hide();
$("#exampleForm .k-form-fieldset:nth-child(3)").hide();
$("#exampleForm .k-form-buttons .k-form-submit").hide();
$("#exampleForm .k-form-buttons .k-form-clear").hide();
$(".last-step-content").show();
} else {
$("#exampleForm .k-form-fieldset:first").show();
$("#exampleForm .k-form-fieldset:nth-child(2)").hide();
$("#exampleForm .k-form-fieldset:nth-child(3)").hide();
$("#exampleForm .k-form-buttons .k-form-submit").hide();
$("#exampleForm .k-form-buttons .k-form-clear").show();
$(".last-step-content").hide();
}
}
</script>
<style>
.k-stepper [class*="correct"] .k-step-indicator {
background-color: green;
border-color: green;
}
.k-stepper [class*="correct"] .k-step-indicator:hover {
background-color: green;
border-color: green;
}
.k-stepper [class*="correct"].k-step-hover .k-step-indicator, .k-stepper [class*="correct"]:hover .k-step-indicator {
background-color: green;
border-color: green;
}
.k-stepper [class*="errors-step"] .k-step-indicator {
background-color: red;
border-color: red;
}
.k-stepper [class*="errors-step"] .k-step-indicator:hover {
background-color: red;
border-color: red;
}
.k-stepper [class*="errors-step"].k-step-hover .k-step-indicator, .k-stepper [class*="errors-step"]:hover .k-step-indicator {
background-color: red;
border-color: red;
}
.k-stepper [class*="save"] .k-step-indicator {
background-color: blue;
border-color: blue;
}
.k-stepper [class*="save"] .k-step-indicator:hover {
background-color: blue;
border-color: blue;
}
.k-stepper [class*="save"].k-step-hover .k-step-indicator, .k-stepper [class*="save"]:hover .k-step-indicator {
background-color: blue;
border-color: blue;
}
.k-stepper [class*="pending"] .k-step-indicator {
background-color: yellow;
border-color: yellow;
}
.k-stepper [class*="pending"] .k-step-indicator:hover {
background-color: yellow;
border-color: yellow;
}
.k-stepper [class*="pending"].k-step-hover .k-step-indicator, .k-stepper [class*="pending"]:hover .k-step-indicator {
background-color: yellow;
border-color: yellow;
}
</style>
For a runnable example implementing the steps above, refer to this REPL.