我的文字在更改时重叠。
但这是时间文本,所以总是在变化
我已经尝试过
TranslateBlt(memhdc,TextBoxRect.left,TextBoxRect.top,TextBoxRect.right,TextBoxRect.bottom,hdc,TextBoxRect.right,TextBoxRect.bottom,RGB(0,0,0));
案例WM_ERASEBKGND: 返回true;
InvalidateRect(NULL,&TextBoxRect,TRUE);
这是我的代码。
HDC hdc = GetDC(NULL);
HDC memhdc;
HBITMAP bgbitmap, oldbitmap;
stringstream stream;
int cur = delay / 10;
stream << "Ms : " << msec;
wchar_t str[120];
mbstowcs_s(NULL, str, 120, stream.str().c_str(), 120);
memhdc = CreateCompatibleDC(hdc);
bgbitmap = CreateCompatibleBitmap(hdc, TextBoxRect.right, TextBoxRect.bottom);
oldbitmap = (HBITMAP) SelectObject(memhdc, bgbitmap);
BLENDFUNCTION bf;
bf.BlendOp = AC_SRC_OVER;
bf.BlendFlags = 0;
bf.SourceConstantAlpha = 255;
bf.AlphaFormat = 0;
AlphaBlend(memhdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, hdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, bf);
SetBkMode(memhdc, TRANSPARENT);
SetTextColor(memhdc, RGB(255, 0, 0));
DrawText(memhdc, str, -1, &TextBoxRect, DT_LEFT | DT_NOCLIP);
BitBlt(hdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, memhdc, TextBoxRect.left, TextBoxRect.top, SRCCOPY);
DeleteObject(SelectObject(memhdc,oldbitmap));
DeleteObject(bgbitmap);
DeleteDC(memhdc);
ReleaseDC(NULL, hdc);
答案 0 :(得分:0)
我想您已经准备好进行透明的数字更改。
您可以尝试同时调用InvalidateRect
和UpdateWindow
来刷新局部区域,因为系统将窗口中的绘制操作视为低优先级操作,可以立即重新绘制与UpdateWindow。
您也可以尝试以下代码,如乔纳森·波特所说的
就像:
AlphaBlend(memhdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, hdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, bf);
SetBkMode(hdc, TRANSPARENT);
SetTextColor(hdc, RGB(255, 0, 0));
BitBlt(hdc, TextBoxRect.left, TextBoxRect.top, TextBoxRect.right, TextBoxRect.bottom, hdc, TextBoxRect.left, TextBoxRect.top, SRCCOPY);
DrawText(hdc, str, -1, &TextBoxRect, DT_LEFT | DT_NOCLIP);