class TaskListView extends TopComponent {


    protected void componentActivated() {
        super.componentActivated();
        assert initialized :
            "#37438 dangling componentActivated event, no componentOpened()" +
            " called at " + this;
        installJumpActions(true);
        ExplorerUtils.activateActions(manager, true);
    }

    protected void componentHidden() {
        hideTaskInEditor();

        // Remove jump actions
        // Cannot do this, because componentHidden can be called
        // after another TaskListView is shown (for example when you
        // switch from one tasklist view to another) so this would
        // cripple the newly showing tasklist view.
        //
        // According to issue #37367 hidden and activated events works
        // together smmothly to get desired result
        installJumpActions(false);
    }

    private Class nextActionClz = null;
    private Class prevActionClz = null;

    /**
     * Assign the Next/Previous build actions to point to the
     * task window
     *
     * @param install true = install, false = deinstall
     */
    private void installJumpActions(boolean install) {
        // TODO - only install if the list is non empty (and call
        // this method from SMI when the list becomes non-empty)
        // In other words, the next action button shouldn't light
        // up when there are no tasks to move to.

        // RFE #40185
        // Make F12 jump to next task
        if (nextActionClz == null) {
            if (lookupAttempted) {
                return;
            }
            lookupAttempted = true;
            ClassLoader systemClassLoader = (ClassLoader) Lookup.getDefault().
                    lookup(ClassLoader.class);
            try {
                nextActionClz = systemClassLoader.
                        loadClass("org.netbeans.core.output2.NextOutJumpAction"); // NOI18N
                prevActionClz = systemClassLoader.
                        loadClass("org.netbeans.core.output2.PreviousOutJumpAction"); // NOI18N
            } catch (Exception e) {
                // Check if the old core/output is installed instead.
                try {
                    nextActionClz = systemClassLoader.
                        loadClass("org.netbeans.core.output.NextOutJumpAction"); // NOI18N
                    prevActionClz = systemClassLoader.
                        loadClass("org.netbeans.core.output.PreviousOutJumpAction"); // NOI18N
                } catch (Exception e2) {
                    // Notify original error.
                    ErrorManager.getDefault().notify(ErrorManager.INFORMATIONAL, e);
                    return;
                }
            }
        }

        CallbackSystemAction nextAction =
                (CallbackSystemAction) SystemAction.get(nextActionClz);
        CallbackSystemAction previousAction =
                (CallbackSystemAction) SystemAction.get(prevActionClz);

        if (install) {
            nextAction.setActionPerformer(new ActionPerformer() {
                public void performAction(SystemAction action) {
                    nextTask();
                }
            });
            previousAction.setActionPerformer(new ActionPerformer() {
                public void performAction(SystemAction action) {
                    prevTask();
                }
            });

            nextCandidate = null;
            prevCandidate = null;
        } else {
            nextAction.setActionPerformer(null);
            previousAction.setActionPerformer(null);
        }
    }

    private boolean lookupAttempted = false;

}