Win32 API - ReaderMode Example

README.md

ReaderMode Example

Design Guidelines and APIs are below:

• Windows Dev Center / Windows desktop applications /
  • Design / Guidelines / Interaction / Mouse and Pointers
  • Develop / Desktop technologies / Desktop App UI / Windows Controls / General Control Reference /
    • Control Functions /
      • DoReaderMode function
      • ReaderScroll callback function
      • TranslateDispatch callback function
    • Control Structures /
      • READERMODEINFO structure

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)
set(CMAKE_LEGACY_CYGWIN_WIN32 0)
project(ReaderModeExample)

if(MSVC)
  add_compile_options("/MP")
endif()

add_executable(ReaderModeExample WIN32
	ReaderModeExample.c
	ReaderMode.c
	ReaderMode.h
)

Makefile

# Makefile for make and nmake

all: ReaderModeExample

ReaderModeExample: ReaderModeExample.c ReaderMode.c ReaderMode.h
	$(CC) -o ReaderModeExample ReaderModeExample.c ReaderMode.c

clean:
	-$(RM) DEL /Q /S ReadModeExample ReaderModeExample.exe ReaderModeExample.obj ReaderMode.obj

ReaderMode.c

/** @file
 * ReaderMode API
 * Copyright (c) 2016 Koichi OKADA. All right reserved.
 * This code is distributed under the MIT license.
 */
#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <stdlib.h>
#include "ReaderMode.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef void (WINAPI *DLLDOREADERMODEPROC)(_In_ PREADERMODEINFO prmi);

static DLLDOREADERMODEPROC pDoReaderMode = NULL;

static LPCTSTR lpszDllName = _T("C:\\Windows\\System32\\comctl32.dll");
static HINSTANCE hinstDll = NULL;

/**
 * Free ReaderMode API.
 * @remarks This function is called automatically.
 */
static void FreeReaderMode(void) {
  if (hinstDll) {
    FreeLibrary(hinstDll);
  }
}

/**
 * Load ReaderMode API.
 * @remarks This function is called automatically.
 */
static DLLDOREADERMODEPROC LoadReaderMode()
{
  pDoReaderMode = NULL;
  atexit(FreeReaderMode);
  hinstDll = LoadLibrary(lpszDllName);
  if (!hinstDll) {
    fprintf(stderr, "Error: in %s line %d: LoadLibrary failed: %s\n", __FILE__, __LINE__, lpszDllName);
    exit(EXIT_FAILURE);
  }
  pDoReaderMode = (DLLDOREADERMODEPROC)GetProcAddress(hinstDll, MAKEINTRESOURCE(383)); // DoReaderMode @ 383
  if (!pDoReaderMode) {
    fprintf(stderr, "Error: in %s line %d: GetProcAddress failed: DoReaderMode\n", __FILE__, __LINE__);
    exit(EXIT_FAILURE);
  }
  return pDoReaderMode;
}

void WINAPI DoReaderMode(_In_ PREADERMODEINFO prmi)
{
  if (!pDoReaderMode) {
    LoadReaderMode();
  }
  if (pDoReaderMode) {
    pDoReaderMode(prmi);
  }
}

#ifdef __cplusplus
}
#endif

ReaderMode.h

/** @file
 * ReaderMode API
 * Copyright (c) 2016 Koichi OKADA. All right reserved.
 * This code is distributed under the MIT license.
 */
#ifndef READERMODE_H
#define READERMODE_H

#include <windows.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @see [READERMODEINFO structure](https://msdn.microsoft.com/en-us/library/windows/desktop/bb775524.aspx)
 */
typedef struct tagReaderModeInfo READERMODEINFO, *PREADERMODEINFO;

/**
 * @see [ReaderScroll callback function](https://msdn.microsoft.com/en-us/library/windows/desktop/bb775729.aspx)
 */
typedef BOOL (CALLBACK *PFNREADERSCROLL)(_In_ PREADERMODEINFO prmi, _In_ int dx, _In_ int dy);

/**
 * @see [TranslateDispatch callback function](https://msdn.microsoft.com/en-us/library/windows/desktop/bb775736.aspx)
 */
typedef BOOL (CALLBACK *PFNREADERTRANSLATEDISPATCH)(_In_ LPMSG lpmsg);

/**
 * @see [READERMODEINFO structure](https://msdn.microsoft.com/en-us/library/windows/desktop/bb775524.aspx)
 */
struct tagReaderModeInfo {
  UINT                       cbSize;
  HWND                       hwnd;
  DWORD                      fFlags;
  LPRECT                     prc;
  PFNREADERSCROLL            pfnScroll;
  PFNREADERTRANSLATEDISPATCH pfnDspatch;
  LPARAM                     lParam;
};

#define RMF_ZEROCURSOR     0x01
#define RMF_VERTICALONLY   0x02
#define RMF_HORIZONTALONLY 0x04


/**
 * @see [DoReaderMode function](https://msdn.microsoft.com/en-us/library/windows/desktop/bb775524.aspx)
 */
void WINAPI DoReaderMode(_In_ PREADERMODEINFO prmi);

#ifdef __cplusplus
}
#endif

#endif//READERMODE_H

ReaderModeExample.c

/** @file
 * ReaderMode API Example
 * Copyright (c) 2016 Koichi OKADA. All right reserved.
 * This code is distributed under the MIT license.
 */
#include <windows.h>
#include <windowsx.h>
#include <tchar.h>
#include <stdio.h>
#include <stdlib.h>
#include <commctrl.h>
#include "ReaderMode.h"

#pragma comment(lib, "user32.lib")

BOOL CALLBACK ReaderScrollCallback(PREADERMODEINFO prmi, int dx, int dy)
{
  static int i = 0;
  fprintf(stderr, "%6d: %3d, %3d\n", i++, dx, dy);
  return TRUE; // always true
}

static BOOL rmfirst;   // ReaderMode first pass flag.
static BOOL rmmoved;   // ReaderMode moved flag.
static int rmx0, rmy0; // ReaderMode initial position.

BOOL CALLBACK TranslateDispatchCallback(LPMSG lpmsg)
{
  static int x0, y0;
  BOOL fResult = FALSE; // TRUE handled msg, FALSE did not  handle msg and msg will be handleded fault handler.
  
  fprintf(stderr, "msg: %04x\n", lpmsg->message);
  switch (lpmsg->message) {
  case WM_MOUSEMOVE:
    if (rmfirst) {
      rmfirst = FALSE;
      rmmoved = FALSE;
      rmx0 = lpmsg->pt.x;
      rmy0 = lpmsg->pt.y;
    } else if (rmx0 != lpmsg->pt.x || rmy0 != lpmsg->pt.y) {
      rmmoved = TRUE;
    }
    fprintf(stderr, "      : %3d, %3d\n", lpmsg->pt.x, lpmsg->pt.y);
    break;
  case WM_MBUTTONUP:
    if (rmfirst || !rmmoved) {
      fResult = TRUE; // Keep ReaderMode if cursor did not move.
    } else {
      // WM_MBUTTONUP will finish ReaderMode at default handler.
      // But cursor will not be recoverd.
      SetCursor(LoadCursor(NULL, IDC_ARROW)); // Set deafult cursor.
    }
    break;
  }
  
  return fResult;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
  switch (uMsg) {
  case WM_DESTROY:
    PostQuitMessage(0);
    return 0;
  case WM_MBUTTONDOWN:
    {
      int x = GET_X_LPARAM(lParam);
      int y = GET_Y_LPARAM(lParam);
      int w = 8;
      RECT r = {x-w, y-w, x+w, y+w};
      READERMODEINFO rmi = {
        sizeof(READERMODEINFO),
        hwnd,
        RMF_ZEROCURSOR,
        &r,
        ReaderScrollCallback,
        TranslateDispatchCallback,
        0
      };
      rmfirst = TRUE;
      DoReaderMode(&rmi);
    }
    return 0;
  }
  return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
  const TCHAR CLASS_NAME[]  = _T("ReaderModeExample");
  
  WNDCLASS wc = {
    0,                           // Style
    WndProc,                     // WndProc
    0,                           // ClsWxtra
    0,                           // WndExtra
    hInstance,                   // Instance
    NULL,                        // Icon
    LoadCursor(NULL, IDC_ARROW), // Cursor
    NULL,                        // BG
    NULL,                        // Menu name
    CLASS_NAME                   // Class name
  };
  
  RegisterClass(&wc);
  
  HWND hwnd = CreateWindowEx(
    0,                   // Optional window style
    CLASS_NAME,          // Window class
    CLASS_NAME,          // Window text
    WS_OVERLAPPEDWINDOW, // Window style
    CW_USEDEFAULT,       // x
    CW_USEDEFAULT,       // y
    CW_USEDEFAULT,       // w
    CW_USEDEFAULT,       // h
    NULL,                // Parent window
    NULL,                // Menu
    hInstance,           // Instance
    NULL                 // Additional application data
  );
  if (hwnd == NULL) {
    fprintf(stderr, "Error: in %s line %d: CreateWindowEx failed.\n", __FILE__, __LINE__);
    return EXIT_FAILURE;
  }
  
  ShowWindow(hwnd, nCmdShow);
  
  MSG msg;
  while (GetMessage(&msg, NULL, 0,0)) {
    TranslateMessage(&msg);
    DispatchMessage(&msg);
  }
  
  return EXIT_SUCCESS;
}