Vue conditional style binding:In Vue, conditional style binding enables developers to dynamically apply CSS styles to an element based on a certain condition. This can be achieved using the v-bind or : shorthand directive along with the v-bind:style or :style directive, followed by an object containing CSS property-value pairs. The object is populated with key-value pairs where the key represents the CSS property name, and the value is the property value. The condition is specified in the object’s value as an expression which evaluates to a Boolean value. When the condition is true, the associated style properties are applied to the element. Conversely, if the condition is false, the element remains unaffected.

How do you use conditional style binding in Vue js?

This code is for creating a simple toggleable dark mode feature in a Vue.js app. It includes a div element with some content inside it, including a button that toggles a boolean value (isDarkMode) when clicked.

The text color of a paragraph element within the div is conditionally bound to the isDarkMode value using a computed property (textColor), which returns either “white” or “black” depending on the boolean value.

The background color of the div is also conditionally bound using another computed property (backgroundColor), which returns either “black” or “white” depending on the isDarkMode value.

Finally, the computedStyles computed property is used to combine these styles into an object that is bound to the div element’s style attribute using Vue’s style binding syntax (:style). This object also includes a padding of 20px.

Overall, this code demonstrates how to use conditional style binding in Vue.js to create a simple dark mode feature that toggles the background and text colors of an element.

Vue conditional style binding Example

 <div id="app">
        <div :style="computedStyles">
            <p :style="{color: textColor}">
                This text will change color based on the value of isDarkMode.
            </p>
            <button @click="isDarkMode = !isDarkMode">
                {{ isDarkMode ? "Disable" : "Enable" }} Dark Mode
            </button>
        </div>
    </div>
    <script type="module">
        const app = new Vue({
            el: "#app", // Set the root element of the app
            data() {
                return {
                    isDarkMode: false,
                };
            },
            computed: {
                textColor() {
                    return this.isDarkMode ? "white" : "black";
                },
                backgroundColor() {
                    return this.isDarkMode ? "black" : "white";
                },
                computedStyles() {
                    return {
                        color: this.textColor,
                        backgroundColor: this.backgroundColor,
                        padding: "20px",
                    };
                },
            },
        });
    </script>

output of Vue conditional style binding