1 virtual bool nativeEvent(const QByteArray &, void *, long *) Q_DECL_OVERRIDE;
  2
  3 {
  4
  5     Q_UNUSED(eventType);
  6
  7     MSG* msg = reinterpret_cast(message);
  8
  9     if (winEvent(msg, result))
 10
 11     {
 12
 13         return true;
 14
 15     }
 16
 17     else
 18
 19     {
 20
 21         return QWidget::nativeEvent(eventType, message, result);
 22
 23     }
 24
 25 }
 26
 27 如下方法是在qt事件循环之前调用的，如果返回值为true，则该事件循环不进入qt事件循环，否则进入，result是一个输出型参数，我们可以通过赋值给result不同的值，来控制鼠标的状态
 28
 29 HTCAPTION：鼠标可以拖拽
 30
 31 HTLEFT / HTRIGHT：鼠标可以左右拖拽
 32
 33 HTTOP / HTBOTTOM：鼠标可以上下拖拽
 34
 35 HTTOPLEFT / HTBOTTOMRIGHT：鼠标可以左上或者右下拖拽
 36
 37 HTTOPRIGHT / HTBOTTOMLEFT：鼠标可以右上或者左下拖拽
 38
 39 bool CCailianMainWindow::winEvent(MSG *message, long *result)
 40
 41 {
 42
 43     static int width = 4;//可检测到鼠标状态的宽度
 44
 45     bool res = false;
 46
 47     if (isMaximized())
 48
 49     {
 50
 51         return res;
 52
 53     }
 54
 55     switch (message->message)
 56
 57     {
 58
 59     case WM_NCHITTEST:
 60
 61         int xPos = GET_X_LPARAM(message->lParam) - this->frameGeometry().x();
 62
 63         int yPos = GET_Y_LPARAM(message->lParam) - this->frameGeometry().y();
 64
 65         if (QWidget * childW = this->childAt(xPos, yPos))
 66
 67         {
 68
 69             if (childW == m_WindowTitle)//我自己的窗口头，支持鼠标拖拽
 70
 71             {
 72
 73                 *result = HTCAPTION;
 74
 75                 res = true;
 76
 77             }
 78
 79         }
 80
 81         else
 82
 83         {
 84
 85             return res;
 86
 87         }
 88
 89         if (xPos >= 0 && xPos < width)
 90
 91         {
 92
 93             *result = HTLEFT;
 94
 95             res = true;
 96
 97         }
 98
 99         if (xPos > (this->width() - width) && xPos < this->width())
100
101         {
102
103             *result = HTRIGHT;
104
105             res = true;
106
107         }
108
109         if (yPos >= 0 && yPos < width)
110
111         {
112
113             *result = HTTOP;
114
115             res = true;
116
117         }
118
119         if (yPos > (this->height() - width) && yPos < this->height())
120
121         {
122
123             *result = HTBOTTOM;
124
125             res = true;
126
127         }
128
129         if (xPos >= 0 && xPos < width && yPos >= 0 && yPos < width)
130
131         {
132
133             *result = HTTOPLEFT;
134
135             res = true;
136
137         }
138
139         if (xPos > (this->width() - width) && xPos < this->width() && yPos >= 0 && yPos < width)
140
141         {
142
143             *result = HTTOPRIGHT;
144
145             res = true;
146
147         }
148
149         if (xPos >= 0 && xPos < width && yPos >(this->height() - width) && yPos < this->height())
150
151         {
152
153             *result = HTBOTTOMLEFT;
154
155             res = true;
156
157         }
158
159         if (xPos > (this->width() - width) && xPos < this->width() && yPos >(this->height() - width) && yPos < this->height())
160
161         {
162
163             *result = HTBOTTOMRIGHT;
164
165             res = true;
166
167         }
168
169     }
170
171     return res;
172
173 }

 1 case WM_NCLBUTTONDBLCLK:
 2
 3 {
 4
 5     HWND hWnd = (HWND)this->winId();
 6
 7     if (::IsZoomed(hWnd))
 8
 9     {
10
11         ShowWindow(hWnd, SW_RESTORE);
12
13     }
14
15     else
16
17     {
18
19         ShowWindow(hWnd, SW_MAXIMIZE);
20
21     }
22
23     res = false;
24
25 }
26
27 break;