如何使用纯 WINAPI 在渐变背景上显示控件？
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【中文标题】如何使用纯 WINAPI 在渐变背景上显示控件？【英文标题】：How do I show controls on top of a gradient background with pure WINAPI? 【发布时间】：2020-11-26 02:53:25 【问题描述】：在我的程序中，我试图创建一个子窗口（通过CreateWindow("STATIC", ...)）来包含一些其他控件，例如编辑框和按钮。但是，我希望这个静态控件的背景是渐变的。
我的目标是让子窗口看起来像这样：
到目前为止，我的努力已经使创建的窗口具有可见的控件，但一旦使用WM_ERASEBKGND 重新绘制，控件就会隐藏在绘制的渐变后面。
我可以找到很多关于绘制渐变（或其他此类图形背景）以及独立创建带有控件的窗口的示例。但我还没有找到任何同时拥有两者的资源。
这是我的示例代码：
#include <windows.h>
#pragma comment( lib, "Msimg32" ) // load that dll for GradientFill
// Global macros
inline COLOR16 ToColor16(BYTE byte) return byte << 8;
inline COLOR16 RVal16(COLORREF color) return ToColor16(GetRValue(color));
inline COLOR16 GVal16(COLORREF color) return ToColor16(GetGValue(color));
inline COLOR16 BVal16(COLORREF color) return ToColor16(GetBValue(color));
// Global variables
HINSTANCE hInst;
// Forward declarations
LRESULT CALLBACK WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);
// Entry point
int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE, PWSTR pCmdLine, int nCmdShow)
// Register the window class.
const TCHAR CLASS_NAME[] = "mcvewinapi";
WNDCLASS wc = ;
wc.lpfnWndProc = WndProc;
wc.hInstance = hInstance;
wc.lpszClassName = CLASS_NAME;
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wc.hCursor = LoadCursor(nullptr, IDC_ARROW);
RegisterClass(&wc);
// Create the window.
HWND hwnd = CreateWindowEx(
0, // Optional window styles.
CLASS_NAME, // Window class
"MCVE WINAPI", // Window text
WS_OVERLAPPEDWINDOW, // Window style
// Size and position
300, //horizontal position
50, //vertical position
700, //width
500, //height
NULL, // Parent window
NULL, // Menu
hInstance, // Instance handle
NULL // Additional application data
);
hInst = hInstance;
if (hwnd == NULL)
return 0;
ShowWindow(hwnd, nCmdShow);
// Run the message loop.
MSG msg = ;
while (GetMessage(&msg, NULL, 0, 0))
TranslateMessage(&msg);
DispatchMessage(&msg);
return 0;
// vill geven area with vertical gradient
void VerticalGradient(HDC hDC, const RECT &RectToFill, COLORREF rgbTop, COLORREF rgbBottom)
GRADIENT_RECT gradRect;
TRIVERTEX TriVert[2];
// references for the verticies
gradRect.UpperLeft = 0; // point to TriVert[0]
gradRect.LowerRight = 1; // point to TriVert[1]
//setup top of gradient attributes
TriVert[0].x = RectToFill.left - 1;
TriVert[0].y = RectToFill.top - 1;
TriVert[0].Red = RVal16(rgbTop);
TriVert[0].Green = GVal16(rgbTop);
TriVert[0].Blue = BVal16(rgbTop);
TriVert[0].Alpha = 0x0000;
//setup bottom of gradient attributes
TriVert[1].x = RectToFill.right;
TriVert[1].y = RectToFill.bottom;
TriVert[1].Red = RVal16(rgbBottom);
TriVert[1].Green = GVal16(rgbBottom);
TriVert[1].Blue = BVal16(rgbBottom);
TriVert[1].Alpha = 0x0000;
// draw the shaded rectangle
GradientFill(hDC, TriVert, 2, &gradRect, 1, GRADIENT_FILL_RECT_V);
// discover area to fill with gradient
void vFill(HWND ctrlhwnd)
HDC gBoxDC;
HWND gBoxH;
RECT gBoxR;
POINT xWhere;
// get rectangle from control
gBoxH = ctrlhwnd;
GetWindowRect(gBoxH, &gBoxR);
// get DC for control
gBoxDC = GetDC(gBoxH);
// load up RECT from POINT
xWhere = gBoxR.left, gBoxR.top ;
ScreenToClient(gBoxH, &xWhere);
gBoxR.left = xWhere.x + 2;
gBoxR.top = xWhere.y + 2;
// load up RECT from POINT
xWhere = gBoxR.right, gBoxR.bottom ;
ScreenToClient(gBoxH, &xWhere);
gBoxR.right = xWhere.x - 1;
gBoxR.bottom = xWhere.y - 1;
//paint area
VerticalGradient(gBoxDC, gBoxR, RGB(250, 191, 145), RGB(191, 191, 191));
ReleaseDC(gBoxH, gBoxDC);
// Processes messages for the main window.
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
switch (message)
case WM_CREATE:
struct wAnchor
int udPos;
int lrPos;
int width;
int height;
;
wAnchor Section1[4], TextLine;
unsigned int LineHeight, k;
HWND FillBox;
LineHeight = 24;
Section1[1].lrPos = 5;
Section1[1].udPos = 20;
Section1[1].width = 325;
Section1[1].height = 360;
TextLine.lrPos = Section1[1].lrPos + 5;
TextLine.udPos = Section1[1].udPos + 5;
TextLine.width = 0;
TextLine.height = LineHeight;
k = 1;
FillBox = CreateWindow("STATIC",
"",
WS_VISIBLE | WS_CHILD | WS_BORDER | WS_EX_CLIENTEDGE,
Section1[1].lrPos,
Section1[1].udPos,
Section1[1].width,
Section1[1].height,
hWnd, // child of parent
(HMENU)8200,
hInst,
NULL);
CreateWindow("STATIC",
"Section title",
WS_VISIBLE | WS_CHILD | WS_BORDER | SS_CENTER | WS_EX_CLIENTEDGE,
TextLine.lrPos,
TextLine.udPos + (TextLine.height * k++),
TextLine.width + 315,
TextLine.height,
FillBox, // child of FillBox
(HMENU)8201,
hInst,
NULL);
CreateWindow("STATIC",
"Entry:",
WS_VISIBLE | WS_CHILD | WS_BORDER | WS_EX_CLIENTEDGE,
TextLine.lrPos,
TextLine.udPos + (TextLine.height * k),
TextLine.width + 75,
TextLine.height,
FillBox, // child of FillBox
(HMENU)8202,
hInst,
NULL);
CreateWindow("EDIT", // edit bos
"109",
WS_VISIBLE | WS_CHILD | WS_BORDER | WS_TABSTOP | ES_MULTILINE,
TextLine.lrPos + 75,
TextLine.udPos + (TextLine.height * k),
TextLine.width + 35,
TextLine.height,
FillBox, // child of FillBox
(HMENU)8203,
hInst,
NULL);
CreateWindow(
"BUTTON", // Predefined class; Unicode assumed
"test", // Button text
WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON, // Styles
50, // x position
150, // y position
50, // Button width
30, // Button height
FillBox, // child of FillBox
(HMENU)8204, // No menu
hInst,
NULL); // Pointer not needed
UpdateWindow(FillBox);
break;
case WM_PAINT:
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hWnd, &ps);
EndPaint(hWnd, &ps);
break;
case WM_ERASEBKGND:
vFill(GetDlgItem(hWnd, 8200)); //fill background with gradient
return 1L;
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
return 0;
最初，在我调整窗口大小之前不绘制渐变，然后渐变覆盖控件。当然，我希望根据需要重新绘制渐变，但控件保持可见。
我该如何做到这一点？
【问题讨论】：
【参考方案1】：您可以将WS_CLIPCHILDREN 样式添加到父窗口：
FillBox = CreateWindow(TEXT("STATIC"),
TEXT(""),
WS_VISIBLE | WS_CHILD | WS_BORDER | WS_EX_CLIENTEDGE | WS_CLIPCHILDREN,
Section1[1].lrPos,
Section1[1].udPos,
Section1[1].width,
Section1[1].height,
hWnd, // child of parent
(HMENU)8200,
hInst,
NULL);
在绘制父窗口时，这将不包括其子窗口，这对我有用：
【讨论】：
【参考方案2】：如果您要创建一个窗口来充当某些控件的容器，那么显而易见的选择通常是创建一个对话框。它已经（自动）处理了你现在正在做的大部分事情，以及一些你可能想要但还没有做的事情（比如使用标签在控件之间移动）。
因此，例如，从通用 Windows 应用程序开始，我更改了默认的 About 框以大致托管您想要的控件，然后在应用程序初始化时将其作为无模式对话框弹出。
// frame.cpp : Defines the entry point for the application.
//
#include "framework.h"
#include "frame.h"
#pragma comment( lib, "Msimg32" ) // load that dll for GradientFill
#define MAX_LOADSTRING 100
// Global Variables:
HINSTANCE hInst; // current instance
WCHAR szTitle[MAX_LOADSTRING]; // The title bar text
WCHAR szWindowClass[MAX_LOADSTRING]; // the main window class name
// Forward declarations of functions included in this code module:
ATOM MyRegisterClass(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM);
int APIENTRY wWinMain(_In_ HINSTANCE hInstance,
_In_opt_ HINSTANCE hPrevInstance,
_In_ LPWSTR lpCmdLine,
_In_ int nCmdShow)
UNREFERENCED_PARAMETER(hPrevInstance);
UNREFERENCED_PARAMETER(lpCmdLine);
// TODO: Place code here.
// Initialize global strings
LoadStringW(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadStringW(hInstance, IDC_FRAME, szWindowClass, MAX_LOADSTRING);
MyRegisterClass(hInstance);
// Perform application initialization:
if (!InitInstance (hInstance, nCmdShow))
return FALSE;
HACCEL hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_FRAME));
MSG msg;
// Main message loop:
while (GetMessage(&msg, nullptr, 0, 0))
if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
TranslateMessage(&msg);
DispatchMessage(&msg);
return (int) msg.wParam;
//
// FUNCTION: MyRegisterClass()
//
// PURPOSE: Registers the window class.
//
ATOM MyRegisterClass(HINSTANCE hInstance)
WNDCLASSEXW wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_FRAME));
wcex.hCursor = LoadCursor(nullptr, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wcex.lpszMenuName = MAKEINTRESOURCEW(IDC_FRAME);
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));
return RegisterClassExW(&wcex);
//
// FUNCTION: InitInstance(HINSTANCE, int)
//
// PURPOSE: Saves instance handle and creates main window
//
// COMMENTS:
//
// In this function, we save the instance handle in a global variable and
// create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
hInst = hInstance; // Store instance handle in our global variable
HWND hWnd = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, nullptr, nullptr, hInstance, nullptr);
if (!hWnd)
return FALSE;
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
return TRUE;
//
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.
//
// WM_COMMAND - process the application menu
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
//
//
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
static HWND dialog;
switch (message)
case WM_CREATE:
dialog = CreateDialog(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
ShowWindow(dialog, SW_SHOW);
break;
case WM_COMMAND:
int wmId = LOWORD(wParam);
// Parse the menu selections:
switch (wmId)
case IDM_EXIT:
DestroyWindow(hWnd);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
break;
case WM_PAINT:
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hWnd, &ps);
// TODO: Add any drawing code that uses hdc here...
EndPaint(hWnd, &ps);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
return 0;
inline COLOR16 ToColor16(BYTE byte) return byte << 8;
inline COLOR16 RVal16(COLORREF color) return ToColor16(GetRValue(color));
inline COLOR16 GVal16(COLORREF color) return ToColor16(GetGValue(color));
inline COLOR16 BVal16(COLORREF color) return ToColor16(GetBValue(color));
// Message handler for about box.
INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
UNREFERENCED_PARAMETER(lParam);
switch (message)
case WM_INITDIALOG:
return (INT_PTR)TRUE;
case WM_ERASEBKGND:
COLORREF rgbTop(RGB(250, 191, 145));
COLORREF rgbBottom(RGB(191, 191, 191));
RECT RectToFill;
GetClientRect(hDlg, &RectToFill);
GRADIENT_RECT gradRect;
TRIVERTEX TriVert[2];
// references for the verticies
gradRect.UpperLeft = 0; // point to TriVert[0]
gradRect.LowerRight = 1; // point to TriVert[1]
//setup top of gradient attributes
TriVert[0].x = RectToFill.left - 1;
TriVert[0].y = RectToFill.top - 1;
TriVert[0].Red = RVal16(rgbTop);
TriVert[0].Green = GVal16(rgbTop);
TriVert[0].Blue = BVal16(rgbTop);
TriVert[0].Alpha = 0x0000;
//setup bottom of gradient attributes
TriVert[1].x = RectToFill.right;
TriVert[1].y = RectToFill.bottom;
TriVert[1].Red = RVal16(rgbBottom);
TriVert[1].Green = GVal16(rgbBottom);
TriVert[1].Blue = BVal16(rgbBottom);
TriVert[1].Alpha = 0x0000;
HDC dc = GetDC(hDlg);
GradientFill(dc, TriVert, 2, &gradRect, 1, GRADIENT_FILL_RECT_V);
ReleaseDC(hDlg, dc);
return TRUE;
case WM_COMMAND:
if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
EndDialog(hDlg, LOWORD(wParam));
return (INT_PTR)TRUE;
break;
return (INT_PTR)FALSE;
我并没有真正完成从模式对话框到无模式对话框的转换（例如，无模式对话框通常没有 OK 按钮，也没有处理其被按下的代码，但它仍然足以理解这个想法它的外观：
【讨论】：
一个对话框会更容易，但是我的例子只是来自一个更大的项目。我的需要实际上是在选项卡控件的一页上拥有这样的容器。但感谢您的帮助。以上是关于如何使用纯 WINAPI 在渐变背景上显示控件？的主要内容，如果未能解决你的问题，请参考以下文章