简化实现qt中的信号阻塞blockSignals

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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。

[代码] cpp代码

1. void ImEffectWidget::slotSlider(int pos)
   
2. {
   
3. static int oldPos = 0;
   
4. if (oldPos != pos)
   
5. {
   
6.   QRect r;
   
7.   QObject *o = sender();
   
8. //
   
9.   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. }

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[代码] ImSignalBlock.h

1. #ifndef IMSIGNALBLOCK_H_
   
2. #define IMSIGNALBLOCK_H_
   
3. #include <QObject>
   
4. class ImSignalBlock
   
5. {
   
6. public:
   
7. ImSignalBlock();
   
8. ~ImSignalBlock();
   
9.   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. }

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