Qt實現桌面動態背景雪花飄落程序，qt雪花

Qt實現桌面動態背景雪花飄落程序，qt雪花

        曾經收到過一份禮物，一個雪花飄落的程序，覺得效果很炫，通過前幾篇的學習，我們已經掌握了貼圖的一些技巧了，那麼現在就可以自己實現了（當然你必須先擁有qt信號與槽的基礎知識），這裡先看效果，然後再分析如何實現。

效果圖：

  1:     //讓程序無邊框

  2:     setWindowFlags( Qt::FramelessWindowHint );

  3:     //讓程序背景透明

  4:     setAttribute(Qt::WA_TranslucentBackground, true);

2、建立雪花池、飄落、回收的聯動，形成一個循環系統

  1: connect(&m_snowWait, SIGNAL(falling(SNOWLIST*)), &m_snowFalling, SLOT(AcceptSnow(SNOWLIST*)));
  2: connect(&m_snowFalling, SIGNAL(snowLander(SNOWLIST*)), &m_snowLander, SLOT(LanderSnow(SNOWLIST*)));
  3: connect(&m_snowLander, SIGNAL(snowRecycle(SNOWLIST*)), &m_snowWait, SLOT(SnowRecycle(SNOWLIST*)));

3、每一朵雪花我們可以用一個button來承載，並為每一朵雪花定義飄落的行為。

雪花節點頭文件：

  1: #include <QToolButton>
  2: #include <QPropertyAnimation>
  3: class QPixmap;
  4: class QPaintEvent;
  5: class QPoint;
  6: class QSize;
  7: 
  8: class SnowNode : public QToolButton
  9: {
 10: public:
 11:     static const int MAXSWOW ;
 12:     SnowNode(QWidget *parent = 0);
 13:     QSize GetSnowSize();
 14:     bool IsLander();
 15:     void InitSnow();
 16:     void FallingAnimation();
 17: 
 18: protected:
 19:     void paintEvent(QPaintEvent *event);
 20: private:
 21:     QString GetImgFileName();
 22: private:
 23:     QPixmap m_pixmap;
 24:     QPropertyAnimation *m_animation;
 25:     QSize m_areaSize;
 26: };

雪花節點實現文件：

  1: #include "pubbase.h"
  2: #include "snownode.h"
  3: #include <QSize>
  4: #include <QPoint>
  5: #include <QBitmap>
  6: #include <QPixmap>
  7: #include <QToolButton>
  8: #include <QApplication>
  9: #include <QDesktopWidget>
 10: #include <QGraphicsScene>
 11: #include <QGraphicsView>
 12: const int SnowNode::MAXSWOW = 19;
 13: 
 14: SnowNode::SnowNode(QWidget *parent):
 15:     QToolButton(parent),m_animation(new QPropertyAnimation(this, "geometry"))
 16: {
 17:     //必須設置為無邊框,否則可見區域和圖片繪制區域將出現不重疊
 18:     setWindowFlags( Qt::FramelessWindowHint );
 19:     resize(GetSnowSize());
 20:     //對圖片進行縮放
 21:     m_pixmap.load(GetImgFileName());
 22:     m_pixmap = m_pixmap.scaled(this->size(),Qt::IgnoreAspectRatio);
 23:     setHidden(true);
 24:     m_areaSize.setWidth(QApplication::desktop()->width());
 25:     m_areaSize.setHeight(QApplication::desktop()->height());
 26: }
 27: 
 28: //初始化雪花
 29: void SnowNode::InitSnow()
 30: {
 31:     this->move(qrand() % m_areaSize.width(), -32);
 32: }
 33: 
 34: //設置雪花動畫
 35: void SnowNode::FallingAnimation()
 36: {
 37:     int x = qrand()% m_areaSize.width();
 38: 	//雪花飄落全程時間
 39:     m_animation->setDuration(8000);
 40:     m_animation->setStartValue(QRect( pos(), size()));
 41:     m_animation->setEndValue(QRect( QPoint(x,m_areaSize.height()), size()));
 42:     m_animation->start();
 43: }
 44: 
 45: //返回雪花是否已著陸
 46: bool SnowNode::IsLander()
 47: {
 48:     if(this->pos().y() >= m_areaSize.height()
 49:         && m_animation->state() == QAbstractAnimation::Stopped
 50:             )
 51:     {
 52:         return true;
 53:     }
 54:     return false;
 55: }
 56: 
 57: void SnowNode::paintEvent(QPaintEvent *event)
 58: {
 59:     //繪制背景圖片
 60:     this->setIcon(QIcon(m_pixmap));
 61:     this->setIconSize(size());
 62:     //將png圖片透明部分設置為穿透
 63:     this->setMask(m_pixmap.mask());
 64:     //繪制
 65:     QToolButton::paintEvent(event);
 66: 
 67: }
 68: 
 69: //每一朵雪花的大小，采用隨機生成
 70: QSize SnowNode::GetSnowSize()
 71: {
 72:     int x = qrand() % 10;
 73:     return x >= 6 ? QSize(32,32) : x >= 3 ? QSize(24,24) : QSize(16,16);
 74: }
 75: 
 76: //獲取雪花文件名
 77: QString SnowNode::GetImgFileName()
 78: {
 79:     return QString().sprintf(":/image/_%d.png", qrand()% MAXSWOW);
 80: }
 81: 

4、替換一個桌面背景

  1: 調用windows API函數來設置桌面背景
  2: ::SystemParametersInfoA(SPI_SETDESKWALLPAPER, 0, (void*)imgFileName, SPIF_UPDATEINIFILE)

5、定義一個定時器，定時投放雪花即可

有想學習的盆友，可以留下你的郵箱地址，我會將完整的源碼發給你。