本文整理汇总了C++中MessagePtr::setUndoState方法的典型用法代码示例。如果您正苦于以下问题：C++ MessagePtr::setUndoState方法的具体用法？C++ MessagePtr::setUndoState怎么用？C++ MessagePtr::setUndoState使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类MessagePtr的用法示例。
在下文中一共展示了MessagePtr::setUndoState方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: handleUndoCommand
bool Client::handleUndoCommand(protocol::Undo &undo)
{
// First check if user context override is used
if(undo.overrideId()) {
undo.setContextId(undo.overrideId());
}
// Undo history is limited to last UNDO_HISTORY_LIMIT undopoints
// or the latest snapshot point, whichever comes first
// Clients usually store more than that, but to ensure a consistent
// experience, we enforce the limit here.
if(undo.points()>0) {
// Undo mode: iterator towards the beginning of the history,
// marking not-undone UndoPoints as undone.
int limit = protocol::UNDO_HISTORY_LIMIT;
int pos = _session->mainstream().end()-1;
int points = 0;
while(limit>0 && points<undo.points() && _session->mainstream().isValidIndex(pos)) {
MessagePtr msg = _session->mainstream().at(pos);
if(msg->type() == protocol::MSG_SNAPSHOTPOINT)
break;
if(msg->type() == protocol::MSG_UNDOPOINT) {
--limit;
if(msg->contextId() == undo.contextId() && msg->undoState()==protocol::DONE) {
msg->setUndoState(protocol::UNDONE);
++points;
}
}
--pos;
}
// Did we undo anything?
if(points==0)
return false;
// Number of undoable actions may be less than expected, but undo what we got.
undo.setPoints(points);
return true;
} else if(undo.points()<0) {
// Redo mode: find the start of the latest undo sequence, then mark
// (points) UndoPoints as redone.
int redostart = _session->mainstream().end();
int limit = protocol::UNDO_HISTORY_LIMIT;
int pos = _session->mainstream().end();
while(_session->mainstream().isValidIndex(--pos) && limit>0) {
protocol::MessagePtr msg = _session->mainstream().at(pos);
if(msg->type() == protocol::MSG_UNDOPOINT) {
--limit;
if(msg->contextId() == undo.contextId()) {
if(msg->undoState() != protocol::DONE)
redostart = pos;
else
break;
}
}
}
// There may be nothing to redo
if(redostart == _session->mainstream().end())
return false;
pos = redostart;
// Mark undone actions as done again
int actions = -undo.points() + 1;
int points = 0;
while(pos < _session->mainstream().end()) {
protocol::MessagePtr msg = _session->mainstream().at(pos);
if(msg->contextId() == undo.contextId() && msg->type() == protocol::MSG_UNDOPOINT) {
if(msg->undoState() == protocol::UNDONE) {
if(--actions==0)
break;
msg->setUndoState(protocol::DONE);
++points;
}
}
++pos;
}
// Did we redo anything
if(points==0)
return false;
undo.setPoints(-points);
return true;
} else {
// points==0 is invalid
return false;
}
}