For the latest stable version, please use Spring Shell 3.4.0! |
Single Select
A single select component asks a user to choose one item from a list. It is similar to a simple dropbox implementation. The following listing shows an example:
@ShellComponent
public class ComponentCommands extends AbstractShellComponent {
@ShellMethod(key = "component single", value = "Single selector", group = "Components")
public String singleSelector() {
SelectorItem<String> i1 = SelectorItem.of("key1", "value1");
SelectorItem<String> i2 = SelectorItem.of("key2", "value2");
List<SelectorItem<String>> items = Arrays.asList(i1, i2);
SingleItemSelector<String, SelectorItem<String>> component = new SingleItemSelector<>(getTerminal(),
items, "testSimple", null);
component.setResourceLoader(getResourceLoader());
component.setTemplateExecutor(getTemplateExecutor());
SingleItemSelectorContext<String, SelectorItem<String>> context = component
.run(SingleItemSelectorContext.empty());
String result = context.getResultItem().flatMap(si -> Optional.ofNullable(si.getItem())).get();
return "Got value " + result;
}
}
The following screencast shows typical output for a single select component:
The context object is SingleItemSelectorContext
. The following table describes its context variables:
Key | Description |
---|---|
|
The returned value when the component exists. |
|
The visible items, where rows contains maps of name and selected items. |
|
The parent context variables (see SelectorComponentContext Template Variables). |
You can pre-select an item by defining it to get exposed. This is
useful if you know the default and lets the user merely press Enter
to make a choice.
The following listing sets a default:
SelectorItem<String> i1 = SelectorItem.of("key1", "value1");
SelectorItem<String> i2 = SelectorItem.of("key2", "value2");
List<SelectorItem<String>> items = Arrays.asList(i1, i2);
SingleItemSelector<String, SelectorItem<String>> component = new SingleItemSelector<>(getTerminal(),
items, "testSimple", null);
component.setDefaultExpose(i2);