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Toolbar

  • Artikkeli

The Toolbar is an action bar component that provides more flexibility than the default action bar: it can be placed anywhere in the app, its size can be changed, and it can use a color scheme that is different from the app's theme. Also, each app screen can have multiple Toolbars.

Overview

A key design element of any Android activity is an action bar. The action bar is the UI component that is used for navigation, search, menus, and branding in an Android app. In Android versions before Android 5.0 Lollipop, the action bar (also known as the app bar) was the recommended component for providing this functionality.

The Toolbar widget (introduced in Android 5.0 Lollipop) can be thought of as a generalization of the action bar interface – it is intended to replace the action bar. The Toolbar can be used anywhere in an app layout, and it is much more customizable than an action bar. The following screenshot illustrates the customized Toolbar example created in this guide:

Example screenshot of a Toolbar with edit, save, and overflow menu items

There are some important differences between the Toolbar and the action bar:

  • A Toolbar can be placed anywhere in the user interface.

  • Multiple toolbars can be displayed on the same screen.

  • If fragments are used, each fragment can have its own Toolbar.

  • A Toolbar can be configured to span only a partial width of the screen.

  • Because the Toolbar is not bound to the color scheme of the Activity's window decor, it can have a visually distinct color scheme.

  • Unlike the action bar, the Toolbar does not include an icon on the left. Its menus on the right use less space.

  • The Toolbar height is adjustable.

  • Other views can be included inside the Toolbar.

A Toolbar can contain one or more of the following elements:

  • Navigation button

  • A branded logo image

  • Title and subtitle

  • Custom views

  • Action menu

  • Overflow menu

Google's Material Design guidelines recommends taking advantage of these elements to give apps a distinct look (rather than relying solely on an application icon and title).

This guide covers the most commonly-used Toolbar scenarios:

  • Replacing an Activity's default action bar with a Toolbar.

  • Adding a second Toolbar to an Activity.

  • Using the Android Support Library v7 AppCompat library (referred to as AppCompat in the rest of this guide) to deploy Toolbar on earlier versions of Android.

Requirements

Toolbar is available on Android 5.0 Lollipop (API 21) and later. When targeting Android releases earlier than Android 5.0, use the Android Support Library v7 AppCompat, which provides backwards-compatible Toolbar support in a NuGet package. Toolbar Compatibility explains how to use this library.