Angular DropDownButton - Getting Started

jQuery
NOTE
Before you start the tutorial, ensure DevExtreme is installed in your application.
Angular
NOTE
Before you start the tutorial, ensure DevExtreme is installed in your application.
Vue
NOTE
Before you start the tutorial, ensure DevExtreme is installed in your application.
React
NOTE
Before you start the tutorial, ensure DevExtreme is installed in your application.

The DropDownButton combines the functionality of a button and a drop-down menu. You can replace the menu with a custom drop-down control.

This tutorial describes how to configure a DropDownButton that logs user clicks in the browser console (you can open the console to see the messages):

Each section in this tutorial covers a single configuration step. You can also find the full code in the following GitHub repository: getting-started-with-dropdownbutton.

Create a DropDownButton

You can use the following code to create a DropDownButton:

jQuery
index.html
index.js
<html>
    <head>
        <!-- ... -->
        <script type="text/javascript" src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
        <link rel="stylesheet" href="https://cdn3.devexpress.com/jslib/22.2.14/css/dx.light.css">
        <script type="text/javascript" src="https://cdn3.devexpress.com/jslib/22.2.14/js/dx.all.js"></script>
        <script type="text/javascript" src="index.js"></script>
    </head>
    <body class="dx-viewport">
        <div id="myDropDownButton"></div>
    </body>
</html>
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // Configuration goes here
    });
});
Angular
app.component.html
app.component.ts
app.module.ts
<dx-drop-down-button
    <!-- Configuration goes here -->
>
</dx-drop-down-button>
import { Component } from '@angular/core';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.css']
})
export class AppComponent {

}
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { AppComponent } from './app.component';

import { DxDropDownButtonModule } from 'devextreme-angular';

@NgModule({
    declarations: [
        AppComponent
    ],
    imports: [
        BrowserModule,
        DxDropDownButtonModule
    ],
    providers: [ ],
    bootstrap: [AppComponent]
})
export class AppModule { }
Vue
App.vue
<template>
    <DxDropDownButton
        <!-- Configuration goes here -->
    />
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxDropDownButton from 'devextreme-vue/drop-down-button';

export default {
    components: {
        DxDropDownButton
    }
}
</script>
React
App.js
import React from 'react';

import 'devextreme/dist/css/dx.light.css';

import DropDownButton from 'devextreme-react/drop-down-button';

class App extends React.Component {
    render() {
        return (
            <DropDownButton
                // Configuration goes here
            />
        );
    }
}
export default App;

Configure the Button

Specify the button's text and/or icon:

jQuery
index.js
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        text: "Sandra Johnson",
        icon: "user"
    });
});
Angular
app.component.html
<dx-drop-down-button
    text="Sandra Johnson"
    icon="user">
</dx-drop-down-button>
Vue
App.vue
<template>
    <DxDropDownButton
        text="Sandra Johnson"
        icon="user"
    />
</template>

<script>
// ...
</script>
React
App.js
// ...
class App extends React.Component {
    render() {
        return (
            <DropDownButton
                text="Sandra Johnson"
                icon="user"
            />
        );
    }
}

Run the code and you should see a button that displays the specified text and icon. Click this button to open a drop-down menu that shows "No data to display." In the next step, we populate the menu.

Populate the Drop-Down Menu

Assign an array to the items property to populate the drop-down menu. Objects in this array should contain data fields that specify text, icons, and other menu item data. The data fields that match those listed in the items section are automatically recognized (icon in the code below). To specify the field that stores item text, use the displayExpr property.

In addition, specify the data field that contains keys used to distinguish between menu items. You can use the keyExpr property to do it.

jQuery
index.js
const actions = [
    { id: 1, text: "My profile", icon: "user" },
    { id: 2, text: "Messages", icon: "email" },
    { id: 3, text: "Contacts", icon: "group" },
    { id: 4, text: "Log out", icon: "runner" }
];

$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // ...
        items: actions,
        keyExpr: "id",
        displayExpr: "text"
    });
});
Angular
app.component.html
app.component.ts
<dx-drop-down-button ...
    [items]="actions"
    keyExpr="id"
    displayExpr="text">
</dx-drop-down-button>
// ...
export class AppComponent {
    actions: Array<{id: Number, text: String, icon: String}> = [
        { id: 1, text: "My profile", icon: "user" },
        { id: 2, text: "Messages", icon: "email" },
        { id: 3, text: "Contacts", icon: "group" },
        { id: 4, text: "Log out", icon: "runner" }
    ];
}
Vue
App.vue
<template>
    <DxDropDownButton ...
        :items="actions"
        key-expr="id"
        display-expr="text"
    />
</template>

<script>
// ...
const actions = [
    { id: 1, text: "My profile", icon: "user" },
    { id: 2, text: "Messages", icon: "email" },
    { id: 3, text: "Contacts", icon: "group" },
    { id: 4, text: "Log out", icon: "runner" }
];

export default {
    // ...
    data() {
        return {
            actions
        }
    }
}
</script>
React
App.js
// ...
const actions = [
    { id: 1, text: "My profile", icon: "user" },
    { id: 2, text: "Messages", icon: "email" },
    { id: 3, text: "Contacts", icon: "group" },
    { id: 4, text: "Log out", icon: "runner" }
];

class App extends React.Component {
    render() {
        return (
            <DropDownButton ...
                items={actions}
                keyExpr="id"
                displayExpr="text"
            />
        );
    }
}

If you run the code and click the button, you should see a list of three actions, but nothing happens when you click any of them. We fix this in the next step.

Handle the Menu Item Click Event

Assign a function to the onItemClick property. In this tutorial, the function logs the selected action's name in the browser's console:

jQuery
index.js
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // ...
        onItemClick: function(e) {
            console.log(e.itemData.text + " was clicked");
        }
    });
});
Angular
app.component.html
app.component.ts
<dx-drop-down-button ...
    (onItemClick)="logAction($event)">
</dx-drop-down-button>
// ...
export class AppComponent {
    // ...
    logAction(e) {
        console.log(e.itemData.text + " was clicked");
    }
}
Vue
App.vue
<template>
    <DxDropDownButton ...
        @item-click="logAction"
    />
</template>

<script>
// ...
export default {
    // ...
    methods: {
        logAction(e) {
            console.log(e.itemData.text + " was clicked");
        }
    }
}
</script>
React
App.js
// ...
class App extends React.Component {
    logAction(e) {
        console.log(e.itemData.text + " was clicked");
    }

    render() {
        return (
            <DropDownButton ...
                onItemClick={this.logAction}
            />
        );
    }
}
export default App;

Run the code, open the browser's console, click the button, and select an action from the drop-down menu. You should see messages like the following:

My profile was clicked
Messages was clicked
Contacts was clicked

Split the Button

The button can execute a custom action instead of opening the drop-down menu. To enable this behavior, split the button into two sections. Set the splitButton property to true and assign a function to the onButtonClick property:

jQuery
index.js
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // ...
        splitButton: true,
        onButtonClick: function() {
            console.log("Main button was clicked");
        }
    });
});
Angular
app.component.html
app.component.ts
<dx-drop-down-button ...
    [splitButton]="true"
    (onButtonClick)="logButtonClick()">
</dx-drop-down-button>
// ...
export class AppComponent {
    // ...
    logButtonClick() {
        console.log("Main button was clicked");
    }
}
Vue
App.vue
<template>
    <DxDropDownButton ...
        :split-button="true"
        @button-click="logButtonClick"
    />
</template>

<script>
// ...
export default {
    // ...
    methods: {
        // ...
        logButtonClick() {
            console.log("Main button was clicked");
        }
    }
}
</script>
React
App.js
// ...
class App extends React.Component {
    // ...
    logButtonClick() {
        console.log("Main button was clicked");
    }

    render() {
        return (
            <DropDownButton ...
                splitButton={true}
                onButtonClick={this.logButtonClick}
            />
        );
    }
}
export default App;

If you run the code, you should see a button divided in two sections. A click on the main section logs "Main button was clicked" into the browser's console. A click on the secondary section opens the drop-down menu.

Enable the Stateful Mode

If the DropDownButton should remember the selected drop-down menu item, switch it to the stateful mode. Set the useSelectMode property to true and make the following replacements in your code:

  • Use onSelectionChanged instead of onItemClick.

    You should track selection changes instead of handling item clicks.

  • Use the selectedItemKey to specify the initially selected item.

    In stateful mode, the main button area displays the text and icon from the selected item. The selectedItemKey allows you to get or set the current selection. Items are identified using keys from the data field that you assigned to the keyExpr property (see the Populate the Drop-Down Menu step).

For more information on the stateful mode, refer to the useSelectMode description.

jQuery
index.js
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // ...
        // text: "Sandra Johnson",
        // icon: "user"
        // onItemClick: function(e) {
        //     console.log(e.itemData.text + " was clicked");
        // },

        useSelectMode: true,
        selectedItemKey: 1,
        onSelectionChanged: function(e) {
            console.log(e.item.text + " was selected; " + e.previousItem.text + " was deselected");
        }
    });
});
Angular
app.component.html
app.component.ts
<dx-drop-down-button ...
    <!-- text="Sandra Johnson" -->
    <!-- icon="user" -->
    <!-- (onItemClick)="logAction($event)" -->
    [useSelectMode]="true"
    [selectedItemKey]="1"
    (onSelectionChanged)="logSelectionChanged($event)">
</dx-drop-down-button>
// ...
export class AppComponent {
    // ...
    // logAction(e) {
    //     console.log(e.itemData.text + " was clicked");
    // }
    logSelectionChanged(e) {
        console.log(e.item.text + " was selected; " + e.previousItem.text + " was deselected");
    }
}
Vue
App.vue
<template>
    <DxDropDownButton
        <!-- text="Sandra Johnson" -->
        <!-- icon="user" -->
        <!-- @item-click="logAction" -->
        :use-select-mode="true"
        :selected-item-key="1"
        @selection-changed="logSelectionChanged"
    />
</template>

<script>
// ...
export default {
    // ...
    methods: {
        // ...
        // logAction(e) {
        //    console.log(e.itemData.text + " was clicked");
        // }
        logSelectionChanged(e) {
            console.log(e.item.text + " was selected; " + e.previousItem.text + " was deselected");
        }
    }
}
</script>
React
App.js
// ...
class App extends React.Component {
    // ...
    // logAction(e) {
    //     console.log(e.itemData.text + " was clicked");
    // }

    logSelectionChanged(e) {
        console.log(e.item.text + " was selected; " + e.previousItem.text + " was deselected");
    }

    render() {
        return (
            <DropDownButton
                // text="Sandra Johnson"
                // icon="user"
                // onItemClick={this.logAction}
                useSelectMode={true}
                selectedItemKey={1}
                onSelectionChanged={this.logSelectionChanged}
            />
        );
    }
}
export default App;

Run the code, open the drop-down menu, and select an item. You should see that the button's text and icon are changed according to the item you selected. In addition, the browser's console should contain messages like the following:

My profile was selected; Log out was deselected
Contacts was selected; My profile was deselected

You have configured basic DropDownButton features. For more information about this UI component, explore the following resources:

Customize the Drop-Down Menu

The DropDownButton uses the Popup component as a drop-down menu. To customize the menu, specify Popup properties in the dropDownOptions object. For example, the following code sets the height of the DropDownButton's menu to 150 pixels:

jQuery
index.js
$(function() {
    $("#myDropDownButton").dxDropDownButton({
        // ...
        dropDownOptions: {
            height: 150
        }
    });
});
Angular
app.component.html
app.component.ts
<dx-drop-down-button ...
    [dropDownOptions]="dropDownOptions">
</dx-drop-down-button>
// ...
export class AppComponent {
    // ...
    dropDownOptions = {
        height: 150
    }
}
Vue
App.vue
<template>
    <DxDropDownButton ...
        :drop-down-options="dropDownOptions"
    />
</template>

<script>
// ...
export default {
    // ...
    data() {
        return {
            // ...
            dropDownOptions: {
                height: 150
            }
        };
    }
}
</script>
React
App.js
// ...
const dropDownOptions = {
    height: 150
};

class App extends React.Component {
    render() {
        return (
            <DropDownButton ...
                dropDownOptions={dropDownOptions}
            />
        );
    }
}

export default App;