/**
* Base class for the actions, which update() method might be potentially slow to be executed
* synchronously in Swing UI thread.
*
* @author max
*/
public abstract class AsyncUpdateAction<T> extends AnAction {
private static final Logger LOG =
Logger.getInstance("#com.intellij.openapi.actionSystem.AsyncUpdateAction");
private static final ExecutorService ourUpdaterService =
ConcurrencyUtil.newSingleThreadExecutor("Action Updater");
// Async update
@Override
public final void update(AnActionEvent e) {
final T data = prepareDataFromContext(e);
final Presentation originalPresentation = e.getPresentation();
if (!forceSyncUpdate(e) && isDumbAware()) {
final Presentation realPresentation = (Presentation) originalPresentation.clone();
ourUpdaterService.submit(
new Runnable() {
@Override
public void run() {
performUpdate(realPresentation, data);
SwingUtilities.invokeLater(
new Runnable() {
@Override
public void run() {
if (originalPresentation.isVisible() != realPresentation.isVisible()) {
LOG.error(
"Async update is not supported for actions that change their visibility."
+ "Either stop extending AsyncUpdateAction or override forceSyncUpdate() to return true."
+ "Action class is: "
+ AsyncUpdateAction.this.getClass().getName());
}
originalPresentation.copyFrom(realPresentation);
}
});
}
});
originalPresentation.setVisible(true);
originalPresentation.setEnabled(false);
} else {
performUpdate(originalPresentation, data);
}
}
// Sync update
@Override
public final void beforeActionPerformedUpdate(@NotNull AnActionEvent e) {
performUpdate(e.getPresentation(), prepareDataFromContext(e));
}
/**
* Get all necessary data from event's DataContext to be used in <code>performUpdate()</code>,
* which is called asynchronously.
*
* @param e action event original update() method have been called with.
* @return prepared data for {@link #performUpdate} method.
*/
protected abstract T prepareDataFromContext(final AnActionEvent e);
/**
* Perform real presentation tweaking here. Be aware of the fact this method may be called in
* thread other than Swing UI thread thus probable restrictions like necessity to call
* ApplcationManager.getApplication().runReadAction() apply.
*
* @param presentation Presentation object to be tweaked.
* @param data necessary data calculated by {@link #prepareDataFromContext(AnActionEvent)}.
*/
protected abstract void performUpdate(Presentation presentation, T data);
/**
* Override this method to return <code>true</code> value if update method cannot be called
* asynchronously for whatever reason.
*
* @param e action event original update() method have been called with.
* @return <code>false</code> if async update is possible and <code>false</code> otherwise.
*/
protected boolean forceSyncUpdate(AnActionEvent e) {
return false;
}
}
