| page.title=Progress and Activity |
| @jd:body |
| |
| <p>When an operation of interest to the user is taking place over a relatively long period of time, |
| provide visual feedback that it's still happening and in the process of being completed.</p> |
| <h2 id="progress">Progress</h2> |
| |
| <p>If you know the percentage of the operation that has been completed, use a determinate progress bar |
| to give the user a sense of how much longer it will take.</p> |
| |
| <img src="{@docRoot}design/media/progress_download.png"> |
| |
| <p>The progress bar should always travel from 0% to 100% completion. Avoid setting the bar to a lower |
| value than a previous value, or using the same progress bar to represent the progress of multiple |
| events, since doing so makes the display meaningless. If you're not sure how long a particular |
| operation will take, use an indeterminate progress indicator.</p> |
| |
| <div class="vspace size-2"> </div> |
| |
| <img src="{@docRoot}design/media/progress_themes.png"> |
| <div class="figure-caption"> |
| Progress bar in Holo Dark and Holo Light. |
| </div> |
| |
| <h2 id="activity">Activity</h2> |
| |
| <p>If you don't know how much longer an operation will continue, use an indeterminate progress |
| indicator. There are two styles available: a flat bar and a circle. Use the one that best fits the |
| available space.</p> |
| |
| |
| <div class="layout-content-row"> |
| <div class="layout-content-col span-6"> |
| |
| <img src="{@docRoot}design/media/progress_activity.png"> |
| |
| </div> |
| <div class="layout-content-col span-7 with-callouts"> |
| |
| <ol> |
| <li class="value-1"><h4>Activity bar (shown with the Holo Dark theme)</h4> |
| <p> |
| |
| An indeterminate activity bar is used at the start of an application download because the Play Store |
| app hasn't been able to contact the server yet, and it's not possible to determine how long it will |
| take for the download to begin. |
| |
| </p> |
| </li> |
| </ol> |
| |
| </div> |
| </div> |
| |
| <div class="layout-content-row"> |
| <div class="layout-content-col span-6"> |
| |
| <img src="{@docRoot}design/media/progress_activity2.png"> |
| |
| </div> |
| <div class="layout-content-col span-7 with-callouts"> |
| |
| <ol> |
| <li class="value-2"><h4>Activity circle (shown with the Holo Light theme)</h4> |
| <p> |
| |
| An indeterminate activity circle is used in the Gmail application when a message is being |
| loaded because it's not possible to determine how long it will take to download the email. |
| |
| </p> |
| </li> |
| </ol> |
| |
| </div> |
| </div> |
| |
| <p>You should only use one activity indicator on screen per activity, and it should appropriately sized |
| for the surrounding context. For example, the largest activity circle works well when displayed in a |
| blank content area, but not in a smaller dialog box.</p> |