public void setChanged(boolean isChanged) {
        this.isChanged = isChanged;
        if (isChanged)
            firePropertyChange(SaveAction.ID, false, isChanged);
        else
            firePropertyChange(SaveAction.ID, true, isChanged);

        if (getDisplayView() != null) {
            for (Canvas curCanvas : getDisplayView().getTabs()) {
                if (curCanvas.isChanged()) {
                    firePropertyChange(SaveAllAction.ID, false, true);
                    return;
                }
            }
            firePropertyChange(SaveAllAction.ID, true, false);
        }
    }