qstack

"""Container containers, which is also called collection, refers to the ability to store other features in memory.Object of a specific type, which is generally a common template class.That is, the QT container class does not have different implementations because of different compilers. The so-called "implicit data sharing" can also be called "copy on write during write ", this technique allows passing value parameters in the container class without additional performance loss. The QT container

to the Walker, Qt also provides its own foreach syntax (c + + 11 also provides a similar syntax, but differs, as described here in the Foreach Loop section).Qt provides a sequential storage container: QList , QLinkedList , QVector , QStack and QQueue . For the vast majority QList of applications, it is the best choice. Although it is a list based on an array implementation, it provides quick forward and backward append operations. If you need a linke

p, uchar val, uchar newVal, QStack Sometimes, due to noise and other effects, the original colors in the areas to be filled are not exactly the same. Fuzzy filling can be used in this case. The so-called fuzzy fill is to set a color range, the points within the color range are considered as the interior point of the area.The following code implements this function. static inline bool fillPoint_Gray( QImage image, QPoint p, uchar low, uchar high, ucha

Sequentail containersQvector Array-like data structure (data insertion at the end has a high validity rate, while data insertion at the center and the header has a high overhead ).Qvector provides [] OperatorsQvector can replace the append () function with the The basic type and pointer in qvector are initialized to 0.Qinilist Qinilist does not provide the [] Operator, so it must be traversed by the iterator.Qlist Array-list: combines qvector The insert/delete operation at the header or tail is

definition of this class, and find pointers to several familiar classes: Qabstracteventdispatcher * eventdispatcher; Qstack Qposteventlist posteventlist; The first is the interface pointer of the event delivery class, the second is the pointer of the event loop class, and the above is the sending time list. Pass Qstack As we can see, Qt Multiple event loops are supported. Qt The multi-thre

Qt container classIt provides platform-independent behavior and implicit data sharing technology. The so-called platform independence, that is, the Qt container class does not have different implementations because of different compilers. The so-called "implicit data sharing" can also be called "copy on write during write ", this technique allows passing value parameters in the container class without additional performance loss. Directory[Hide] 1. Ordered container

, combining the advantages of the above two structures, it supports random access, and inserts and deletes at any end of it are very fast and in the middle of the list, inserts and deletes are also quick. Those who have studied the data structure will clearly understand the structural differences between the three. If you want each item element to be contiguous, you can only use Qvector. Qstring It is a subclass of Qlist Qstack They are implementati

, combining the advantages of the above two structures, it supports random access, and inserts and deletes at any end of it are very fast and in the middle of the list, inserts and deletes are also quick. Those who have studied the data structure will clearly understand the structural differences between the three. If you want each item element to be contiguous, you can only use Qvector. Qstring It is a subclass of Qlist Qstack They are implementati

qmetatypeid qmimedata qmodelindex qmodelindexlist QMultiHash QMultiMap Qmutablehashiterator qmutablelinkedlistiterator qmutablelistiterator qmutablemapiterator QMutableSetIterator Qmutablestringlistiterator qmutablevectoriterator Qmutex qmutexlocker qnodebug qnoimplicitboolcast QObject Qobjectcleanuphandler qobjectdata qobjectlist qobjectuserdata qpair qpersistentmodelindex QPluginLoader QPoinT qpointf qpointer qprocess qqueue qreadlocker qreadwritelock qrect qrectf qregexp qresource QReturnArg

, qwtpickermachine ).Qwteventpattern: mouseselect3, qwteventpattern: keyundo, or qwteventpattern: mouseselect6, qwteventpattern: keyredo walk up and down the zoom stack. qwteventpattern: mouseselect2 or qwteventpattern: keyhome unzoom to the initial size. Qwtplotzoomer isTailored for plots with one X and Y axis, but it is allowed to attach a second qwtplotzoomerThe other axes. Note: The realtime example between des an derived Zoomer class that adds scrollbars to the plot canvas. T

上篇博客我们已经将中缀表达式正确的转换为后缀表达式了。So how does the suffix expression work? The numbers and operators in the suffix expression are required. If the current element is an operator: 1. The right operand is popped out of the stack; 2. The left operand is popped out of the stack; 3. Operation according to the symbol; 4. Presses the result of the operation into the stack. When the traversal is finished, the only number in the stack is the result of the operation.The pseudo code is used to describe it:In this

this way, when the adjacent contacts of the current node have been accessed or no adjacent contacts need to be returned,Then, the queue elements are popped up from the queue node at the top of the stack, and the node elements in the queue are queued in sequence,If the queue has been accessed, it will continue to go out (when the current queue node is empty, it will continue to go out of the stack, and the queue at the top of the next stack will pop up ),Until there is an unaccessed node (the ac

, [this] () {qstring Path = model _-> filepath (currentindex (); If (path. isnull () {qdebug () In this example, when the menu selects rename, it sends a signalrename signal. A qkeyevent object is instantiated in the corresponding slot and its key is set to QT: key_f2, that is, the event that generates the press F2, and then transmits the event to the Event Filter keypressevent that handles the press on the keyboard. achieve this goal. however, this is not too clean. If you want to clean it, yo