简化实现qt中的信号阻塞blockSignals

http://www.oschina.net/code/snippet_54100_1304
QT中经常会用到blockSignals, 且是成对出现，实现时常在函数的开始阻塞信号，在函数的结尾 释放信号。
若里面有大量需要阻塞的变量对象，这样写是件很麻烦的事，代码也比较多。
如果能实现象下面的方式实现，这样能简化很多，且不关心释放 问题.
下面的例子是关于slider与spinbox联动问题,若改slider影响spinbox,反之如此。

标签： 信号阻塞 blockSignals Qt

代码片段(2)[全屏查看所有代码]

1. [代码]cpp代码    跳至 [1] [2] [全屏预览]

01 void ImEffectWidget::slotSlider(int pos)
02 {
03  static int oldPos = 0;
04  if (oldPos != pos)
05  {
06   QRect r;
07   QObject *o = sender();
08 //
09   ImSignalBlock block;
10   block << m_ui.spinBoxTransparent << m_ui.spinBoxVerticalPos
11      << m_ui.spinBoxHerizontalPos << m_ui.spinBoxSTTransparent
12      << m_ui.spinBoxSTVPos;
13   int tabType = m_treeItem->mdata("effect_catalog").toInt();
14   if (tabType == TAB_CATALOG_WATERMARK ){
15    r = m_treeItem->getEffectItem("effect_item_rect").toRect();
16   }
17
18   /* 3. for watermark  ***************************/
19   else if (o->objectName() == "sliderTransparent"){
20    m_ui.spinBoxTransparent->setValue(pos);  //与spinbox关联
21    m_treeItem->setEffectItem("effect_item_transparent", pos);
22   }else if (o->objectName() == "sliderVerticalPos"){
23    r.moveLeft(pos);
24    m_ui.spinBoxVerticalPos->setValue(pos);
25   }else if (o->objectName() == "sliderHorizontalPos"){
26    r.moveTop(pos);
27    m_ui.spinBoxHerizontalPos->setValue(pos);
28   }
29   /* 5. for subtitle  ***************************/
30   else if (o->objectName() == "sliderSTTransparent"){
31    m_ui.spinBoxSTTransparent->setValue(pos);
32    m_treeItem->setMediaData("effect_subtitle_transparent", pos);
33   }else if (o->objectName() == "sliderSTVPos"){
34    m_ui.spinBoxSTVPos->setValue(pos);
35    m_treeItem->setMediaData("effect_subtitle_pos", pos);
36   }
37
38   if (tabType == TAB_CATALOG_WATERMARK ){
39    m_treeItem->setEffectItem("effect_item_rect", r);
40   }
41   sendEffectEvent();   //向sdl发信号
42   oldPos = pos;
43  }
44 }

2. [代码]ImSignalBlock.h    跳至 [1] [2] [全屏预览]

01 #ifndef IMSIGNALBLOCK_H_
02 #define IMSIGNALBLOCK_H_
03 #include <QObject>
04 class ImSignalBlock
05 {
06 public:
07  ImSignalBlock();
08  ~ImSignalBlock();
09   ImSignalBlock &operator<< (QObject *o);
10 private:
11  QList<QObject*> m_objs;
12 };
13 #endif
14 ImSignalBlock.cpp:
15 #include <QDebug>
16 #include "ImSignalBlock.h"
17 ImSignalBlock::ImSignalBlock()
18 {
19 }
20 ImSignalBlock::~ImSignalBlock()
21 {
22  foreach (QObject* o, m_objs)
23  {
24   if (o) o->blockSignals(false);
25  }
26 }
27 ImSignalBlock &ImSignalBlock::operator<< (QObject *o)
28 {
29  if (o)
30  {
31   m_objs.append(o);
32   qDebug() << o->objectName();
33   o->blockSignals(true);
34  }
35  return *this;
36 } http://blog.csdn.net/koilin/article/details/7599223 我有两个QComboBox combo1, combo2： [cpp] view plain copy print ? QComboBox *combo1 = new QComboBox;   QComboBox *combo2 = new QComboBox;   combo1->addItem("1-1");   combo1->addItem("1-2");   combo2->addItem("2-1");   combo2->addItem("2-2");   connect(combo1, SIGNAL(currentIndexChanged(int)), combo2, SLOT(process(int)));   connect(combo2, SIGNAL(currentIndexChanged(int)), combo1, SLOT(process(int)));   QComboBox *combo1 = new QComboBox; QComboBox *combo2 = new QComboBox; combo1->addItem("1-1"); combo1->addItem("1-2"); combo2->addItem("2-1"); combo2->addItem("2-2"); connect(combo1, SIGNAL(currentIndexChanged(int)), combo2, SLOT(process(int))); connect(combo2, SIGNAL(currentIndexChanged(int)), combo1, SLOT(process(int))); 然后是信号处理函数： [cpp] view plain copy print ? void process(int index)   {       QComboBox *combo1 = new QComboBox;       QComboBox *combo2 = new QComboBox;       if (sender() == combo1)       {           combo2->setCurrentIndex(index);       }       else if (sender() == combo2)       {           combo1->setCurrentIndex(index);       }   }   void process(int index) { QComboBox *combo1 = new QComboBox; QComboBox *combo2 = new QComboBox; if (sender() == combo1) { combo2->setCurrentIndex(index); } else if (sender() == combo2) { combo1->setCurrentIndex(index); } } 这样两个combobox之间就产生了死循环。因为不管是手动改变combobox的当前index还是使用函数来设置当前的index都会发出index改变的消息，此时就需要使用关闭信号： [cpp] view plain copy print ? void process(int index)   {       QComboBox *combo1 = new QComboBox;       QComboBox *combo2 = new QComboBox;       if (sender() == combo1)       {           combo2->blockSignals(true);           combo2->setCurrentIndex(index);           combo2->blockSignals(false);       }       else if (sender() == combo2)       {           combo1->blockSignals(true);           combo1->setCurrentIndex(index);           combo1->blockSignals(false);       }   }