progressBar
progressBar
is an indicator that shows the progress of the task or process. The progress can be determinate or indeterminate. Use progressBar
to indicate an ongoing process that takes a noticeable time to finish.
-
XML-element:
progressBar
-
Java class:
ProgressBar
Determinate Progress
By default, progressBar
shows progress in the determinate mode. This mode can give users an idea of how long the process will take — the progress indicator will increase in size based on the value obtained from the process.
The example below displays progress for a simple background task:
<progressBar id="progressBar"/>
@ViewComponent
protected ProgressBar progressBar;
@Autowired
protected BackgroundWorker backgroundWorker;
private static final int ITERATIONS = 6;
@Subscribe
protected void onInit(InitEvent event) {
BackgroundTask<Integer, Void> task = new BackgroundTask<Integer, Void>(100) {
@Override
public Void run(TaskLifeCycle<Integer> taskLifeCycle) throws Exception {
for (int i = 1; i <= ITERATIONS; i++) {
TimeUnit.SECONDS.sleep(1); (1)
taskLifeCycle.publish(i);
}
return null;
}
@Override
public void progress(List<Integer> changes) {
double lastValue = changes.get(changes.size() - 1);
progressBar.setValue(lastValue / ITERATIONS); (2)
}
};
BackgroundTaskHandler taskHandler = backgroundWorker.handle(task);
taskHandler.execute();
}
1 | Some task that takes time to complete |
2 | Set the current progress value which must be within the 0.0 and 1.0 range |
Indeterminate Progress
In the indeterminate mode progressBar
cycles repeatedly along the length of the bar without showing a specific progress value. This mode can be used for a process which doesn’t share its progress value.
To use this mode, set the indeterminate
attribute to true
:
<progressBar id="indeterminateProgressBar" indeterminate="true"/>
Attributes
id - alignSelf - classNames - colspan - height - indeterminate - max - maxHeight - maxWidth - min - minHeight - minWidth - themeNames - value - visible - width
max
Sets the maximum progress value. Reaching this value indicates completion of the process. Default is 1.0
.
themeNames
Sets a different theme to change component’s colors and draw user attention.
-
contrast
- applies more contrasting color scheme. -
error
- signals of an error state. -
success
- indicates success.
Handlers
To generate a handler stub in Jmix Studio, use the Handlers tab of the Jmix UI inspector panel or the Generate Handler action available in the top panel of the view class and through the Code → Generate menu (Alt+Insert / Cmd+N). |
See Also
See Vaadin Docs for more information.