| 40 | } |
| 41 | |
| 42 | bool CommandManager::redo() |
| 43 | { |
| 44 | if (redoStack_.empty()) return true; |
| 45 | |
| 46 | CommandIPtr command = std::move(redoStack_.back()); |
| 47 | if (!command) return false; |
| 48 | |
| 49 | if (command->redo()) { |
| 50 | // Push and pop history stacks. |
| 51 | redoStack_.pop_back(); |
| 52 | undoStack_.push_back(std::move(command)); |
| 53 | return true; |
| 54 | } |
| 55 | else { |
| 56 | // Rollback. |
| 57 | command->undo(); |
| 58 | return false; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | void CommandManager::clear() |
| 63 | { |