Unity內使用桌面的虛擬鍵盤

虛擬鍵盤一般用在觸控螢幕上，也就是觸控電視和手機平板等，當需要讓使用者輸入的時候就很方便，因此在這記錄一下呼叫虛擬鍵盤的做法，之前在網路上找到並在專案中拿來使用的。

首先是創造一個C#的Script，裡面內容直接如下，可以直接複製貼上：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;

public class VirtualKeyboardController : MonoBehaviour {

    void Start ()
    {

    }

    void Update ()
    {

    }

    public class VirtualKeyboard
    {
        [DllImport("user32")]
        static extern IntPtr FindWindow(String sClassName, String sAppName);

        [DllImport("user32")]
        static extern bool PostMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);

        private static Process _onScreenKeyboardProcess = null;

        //Show the touch keyboard (tabtip.exe).
        public void ShowTouchKeyboard()
        {
            ExternalCall("C:\\Program Files\\Common Files\\Microsoft Shared\\ink\\tabtip.exe", null, false);
            //ExternalCall("TABTIP", null, false);
        }

        //Hide the touch keyboard (tabtip.exe).
        public void HideTouchKeyboard()
        {
            uint WM_SYSCOMMAND = 274;
            int SC_CLOSE = 61536;
            IntPtr ptr = FindWindow("IPTip_Main_Window", null);
            PostMessage(ptr, WM_SYSCOMMAND, SC_CLOSE, 0);
        }

        //Show the on screen keyboard (osk.exe).
        public void ShowOnScreenKeyboard()
        {
            //ExternalCall("C:\\Windows\\system32\\osk.exe", null, false);

            if (_onScreenKeyboardProcess == null || _onScreenKeyboardProcess.HasExited)
                _onScreenKeyboardProcess = ExternalCall("OSK", null, false);
        }

        // Hide the on screen keyboard (osk.exe).
        public void HideOnScreenKeyboard()
        {
            if (_onScreenKeyboardProcess != null && !_onScreenKeyboardProcess.HasExited)
                _onScreenKeyboardProcess.Kill();
        }

        /// <summary>
        /// Set size and location of the OSK.exe keyboard, via registry changes.  Messy, but only known method.
        /// </summary>
        /// <param name='rect'>
        /// Rect.
        /// </param>
        public void RepositionOnScreenKeyboard(Rect rect)
        {
            ExternalCall("REG", @"ADD HKCU\Software\Microsoft\Osk /v WindowLeft /t REG_DWORD /d " + (int)rect.x + " /f", true);
            ExternalCall("REG", @"ADD HKCU\Software\Microsoft\Osk /v WindowTop /t REG_DWORD /d " + (int)rect.y + " /f", true);
            ExternalCall("REG", @"ADD HKCU\Software\Microsoft\Osk /v WindowWidth /t REG_DWORD /d " + (int)rect.width + " /f", true);
            ExternalCall("REG", @"ADD HKCU\Software\Microsoft\Osk /v WindowHeight /t REG_DWORD /d " + (int)rect.height + " /f", true);
        }

        private static Process ExternalCall(string filename, string arguments, bool hideWindow)
        {
            ProcessStartInfo startInfo = new ProcessStartInfo();
            startInfo.FileName = filename;
            startInfo.Arguments = arguments;

            // if just command, we do not want to see the console displayed
            if (hideWindow)
            {
                startInfo.RedirectStandardOutput = true;
                startInfo.RedirectStandardError = true;
                startInfo.UseShellExecute = false;
                startInfo.CreateNoWindow = true;
            }

            Process process = new Process();
            process.StartInfo = startInfo;
            process.Start();

            return process;
        }
    }
}

然後在其他地方來做呼叫或關閉，當然虛擬鍵盤呼叫出來後，也可以直接按鍵盤右上角的X來關閉：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class XXX : MonoBehaviour {

    void Start ()
    {
        VirtualKeyboardController.VirtualKeyboard keyboard = new VirtualKeyboardController.VirtualKeyboard();

        keyboard.ShowOnScreenKeyboard();

        keyboard.HideOnScreenKeyboard();
    }

    void Update ()
    {

    }
}

這樣就可以呼叫和關閉螢幕虛擬鍵盤了，網路上有人說這招在Win 10後就沒辦法叫了，因為Microsoft不再放出虛擬鍵盤的控制權，我自己在Win 10使用是無礙啦......