I am making a customizable on-screen keyboard with Unity, but am having trouble figuring out how to get the keyboard to send the keys to whatever window is behind it.
I have tried using a slightly edited version of Louisbob's code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;
using UnityEngine.UI;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using System.Diagnostics;
[SerializeField]
class SendMessages
{
[DllImport("user32.dll")]
public static extern IntPtr PostMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);
public static void sendKeystroke()
{
const uint WM_KEYDOWN = 0x0100;
const uint WM_KEYUP = 0x0101;
IntPtr hWnd;
string processName = "Notepad";
Process[] processList = Process.GetProcesses();
foreach (Process P in processList)
{
if (P.ProcessName.Equals(processName))
{
IntPtr edit = P.MainWindowHandle;
PostMessage(edit, WM_KEYDOWN, (IntPtr)(Keys.B), IntPtr.Zero);
}
}
}
}
public class B_Button : MonoBehaviour
{
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
if(Input.GetMouseButtonDown(0))
{
SendMessages.sendKeystroke();
}
}
}
This code does not return any errors but when I run/build the project and click, no 'B' appears in Notepad. Am I doing something wrong or does the PostMessage function not work with Unity? If it does not work, what else can I do to get this program to work?
Update
I figured out that getting the handle on the window is one or the only problem. I did
Process[] n = Process.GetProcessesByName("Notepad");
foreach (Process p in n)
{
hWnd = p.MainWindowHandle;
UnityEngine.Debug.Log(hWnd);
}
on multiple programs, that were running, and it returned 0 for both mainwindowhandles. I am not sure what is causing this since the applications are running and not hidden, so any advice would be appreciated.
