Cómo mostrar, ocultar, mover o cambiar el tamaño del teclado en pantalla en Java, C#, C++, Visual Basic, Delphi, etc.

Puede usar mensajes de Windows para controlar el teclado virtual.

Ejemplo:

WM_CSKEYBOARD = WM_USER + 192;
WM_CSKEYBOARDMOVE = WM_USER + 193;
WM_CSKEYBOARDRESIZE = WM_USER + 197;

// to show keyboard
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARD, 1, 0);

// to close keyboard
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARD, 2, 0);

// to fade keyboard
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARD, 3, 0);

// to toggle (show/hide) keyboard
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARD, 4, 0);

// to move keyboard (Left, Top - new position)
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARDMOVE, Left, Top);

// to resize keyboard
PostMessage(FindWindow('TFirstForm', 'hvkFirstForm'), WM_CSKEYBOARDRESIZE, Width, Height);

Código de ejemplo de Visual Basic 2008 (VB.NET):

Const WM_CSKEYBOARD = &H400 + 192
Const WM_CSKEYBOARDMOVE = &H400 + 193
Const WM_CSKEYBOARDRESIZE = &H400 + 197
 
Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer
Declare Function PostMessage Lib "user32" Alias "PostMessageA" (ByVal hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
 
    'Open/show Hot Virtual Keyboard in Visual Basic
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 1, 0)
    End Sub
 
    'Close Hot Virtual Keyboard in Visual Basic
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 2, 0)
    End Sub
 
    'Move Hot Virtual Keyboard in Visual Basic; Move it first then show it
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARDMOVE, 200, 200)
        PostMessage(hWnd, WM_CSKEYBOARD, 1, 0)
    End Sub
 
    'Toggle Hot Virtual Keyboard in Visual Basic
    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 4, 0)
    End Sub
 
    'Fade Hot Virtual Keyboard in Visual Basic
    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 3, 0)
    End Sub
 
    'Change the keyboard type and show it
    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        'Change the Registry entry for the required keyboard
        My.Computer.Registry.SetValue("HKEY_CURRENT_USER\Software\ComfortSoftware\hvk", "KeyboardName", "Name of your chosen keyboard")
        'Open the keyboard
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 1, 0)
    End Sub
 
    'Change to another keyboard type and show it
    Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
        'Change the Registry entry for the required keyboard
        My.Computer.Registry.SetValue("HKEY_CURRENT_USER\Software\ComfortSoftware\hvk", "KeyboardName", "Name of another chosen keyboard")
        'Open the keyboard
        Dim hWnd As Integer
        hWnd = FindWindow("TFirstForm", "hvkFirstForm")
        PostMessage(hWnd, WM_CSKEYBOARD, 1, 0)
    End Sub

Código de ejemplo de C#:

using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;

public const Int32 WM_USER = 1024;
public const Int32 WM_CSKEYBOARD = WM_USER + 192;
public const Int32 WM_CSKEYBOARDMOVE = WM_USER + 193;
public const Int32 WM_CSKEYBOARDRESIZE = WM_USER + 197;

[DllImport("user32.dll", EntryPoint = "FindWindow")]
private static extern Int32 FindWindow(string _ClassName, string _WindowName);

[DllImport("User32.DLL")]
public static extern Boolean PostMessage(Int32 hWnd, Int32 Msg, Int32 wParam, Int32 lParam);


Int32 hWnd = FindWindow("TFirstForm", "hvkFirstForm");
PostMessage(hWnd, WM_CSKEYBOARD, 1, 0 ); // Show
PostMessage(hWnd, WM_CSKEYBOARD, 2, 0); // Hide
PostMessage(hWnd, WM_CSKEYBOARDMOVE, 0, 0); // Move to 0, 0
PostMessage(hWnd, WM_CSKEYBOARDRESIZE, 600, 300); // Resize to 600, 300

Código de ejemplo de C++ (sintaxis CLR):

using namespace System::Runtime::InteropServices; 
using namespace System::Security::Permissions; 
using namespace Microsoft::Win32; 
 
const System::UInt32 WM_USER = 1024; 
const System::UInt32 WM_CSKEYBOARD = WM_USER + 192; 
const System::UInt32 WM_CSKEYBOARDMOVE = WM_USER + 193;  
 
[DllImport("user32.dll")] 
extern IntPtr FindWindow(String^ lpClassName, String^ lpWindowName); 
[DllImport("user32.dll")] 
extern IntPtr PostMessage(System::IntPtr hWnd, System::UInt32 Msg, int wParam, int lParam); 
[assembly:RegistryPermissionAttribute(SecurityAction::RequestMinimum, All = "HKEY_CURRENT_USER")]; 
 
 
....blah blah blah you normal code...
 
 
void button1_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
    // Open/show the Hot Virtual Keyboard 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARD, 1, 0); 
} 
void button2_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
        // close the Hot Virtual Keyboard 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARD, 2, 0); 
} 
void button3_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
    //Move the Hot Virtual Keyboard; Move it first then show it 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARDMOVE, 200, 200); 
    PostMessage(hWnd, WM_CSKEYBOARD, 1, 0); 
} 
void button4_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
    //Toggle the Hot Virtual Keyboard 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARD, 4, 0); 
} 
void button5_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
    //Fade the Hot Virtual Keyboard 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARD, 3, 0); 
} 
void button6_Click(System::Object^  sender, System::EventArgs^  e) 
{ 
    //Change the keyboard type and show it 
    System::Object ^kname="NumPad"; 
 
    //Change the Registry entry for the required keyboard 
 
    RegistryKey ^key= Registry::CurrentUser->OpenSubKey ( "Software\\ComfortSoftware\\hvk",true); 
    key->SetValue("KeyboardName",kname); 
 
    //Open the keyboard 
    IntPtr hWnd; 
    hWnd = FindWindow("TFirstForm", "hvkFirstForm"); 
    PostMessage(hWnd, WM_CSKEYBOARD, 1, 0); 
}

Código de ejemplo de Java:

/*
* This file is heavily based on Jawin: http://jawinproject.sourceforge.net/
*
* assumes Hot Virtual Keyboard is loaded...
* 
*/

package client.keyboard;

import java.io.ByteArrayInputStream;
import java.io.IOException;

import org.jawin.COMException;
import org.jawin.FuncPtr;
import org.jawin.ReturnFlags;
import org.jawin.io.LittleEndianInputStream;
import org.jawin.io.LittleEndianOutputStream;
import org.jawin.io.NakedByteStream;

public class ComfortSoftwareKeyboard {

    protected static final String COMFORT_SOFTWARE_WINDOW_NAME = "hvkFirstForm";
    protected static final String COMFORT_SOFTWARE_CLASS_NAME = "TFirstForm";
    
    protected static final int WM_USER = 1024;
    protected static final int WM_CSKEYBOARD = WM_USER + 192;
    protected static final int WM_CSKEYBOARDMOVE = WM_USER + 193;

    protected static final Call FIND_WINDOW = new Call("USER32.DLL", "FindWindowW", "GG:I:", 8);
    protected static final Call POST_MESSAGE = new Call("USER32.DLL", "PostMessageW", "IIII:I:", 16);
    
    private static ComfortSoftwareKeyboard INSTANCE = new ComfortSoftwareKeyboard();

    public static ComfortSoftwareKeyboard getInstance() {
        return INSTANCE;
    }

    protected int getWindowHandle() throws COMException, IOException {
        FuncPtr findWindow = null;
        findWindow = new FuncPtr(FIND_WINDOW.getDllName(), FIND_WINDOW.getFunctionName());
        NakedByteStream bs = new NakedByteStream();
        LittleEndianOutputStream leo = new LittleEndianOutputStream(bs);
        leo.writeStringUnicode(COMFORT_SOFTWARE_CLASS_NAME);
        leo.writeStringUnicode(COMFORT_SOFTWARE_WINDOW_NAME);
        byte[] b = findWindow.invoke(FIND_WINDOW.getParameterDescription(), FIND_WINDOW.getStackSize(), bs, null,
                ReturnFlags.CHECK_FALSE);
        LittleEndianInputStream leis = new LittleEndianInputStream(
                new ByteArrayInputStream(b));
        int l = leis.readInt();
        findWindow.close();
        return l;
    }

    public int move(int x, int y) throws COMException, IOException {
        int hWnd = getWindowHandle();

        FuncPtr postMessage = null;
        postMessage = new FuncPtr(POST_MESSAGE.getDllName(), POST_MESSAGE.getFunctionName());
        NakedByteStream bs = new NakedByteStream();
        LittleEndianOutputStream leo = new LittleEndianOutputStream(bs);

        leo.writeInt(hWnd);
        leo.writeInt(WM_CSKEYBOARDMOVE);
        leo.writeInt(x);
        leo.writeInt(y);

        byte[] b = postMessage.invoke(POST_MESSAGE.getParameterDescription(), POST_MESSAGE.getStackSize(), bs, null,
                ReturnFlags.CHECK_FALSE);
        LittleEndianInputStream leis = new LittleEndianInputStream(
                new ByteArrayInputStream(b));
        int l = leis.readInt();
        postMessage.close();
        return l;
    }
    
    public int setVisible(boolean visible) throws COMException, IOException {
        int hWnd = getWindowHandle();

        FuncPtr postMessage = null;
        postMessage = new FuncPtr(POST_MESSAGE.getDllName(), POST_MESSAGE.getFunctionName());
        NakedByteStream bs = new NakedByteStream();
        LittleEndianOutputStream leo = new LittleEndianOutputStream(bs);

        leo.writeInt(hWnd);
        leo.writeInt(WM_CSKEYBOARD);
        leo.writeInt(visible ? 1 : 2);
        leo.writeInt(0);

        byte[] b = postMessage.invoke(POST_MESSAGE.getParameterDescription(), POST_MESSAGE.getStackSize(), bs, null,
                ReturnFlags.CHECK_FALSE);
        LittleEndianInputStream leis = new LittleEndianInputStream(
                new ByteArrayInputStream(b));
        int l = leis.readInt();
        postMessage.close();
        return l;
    }

    public static void main(String[] args) throws Exception {
        try {
            ComfortSoftwareKeyboard keyboard = ComfortSoftwareKeyboard.getInstance();
            keyboard.setVisible(true);
            Thread.sleep(1000);
            keyboard.setVisible(false);
            Thread.sleep(1000);
            keyboard.setVisible(true);
            for (int i = 0; i < 100;i++) {
                keyboard.move(i, i);
            }
        } catch (COMException e) {
        } finally {
        }
    }
}

class Call {
    private int stackSize;
    private String functionName;
    private String parameterDescription;
    private String dllName;
    
    public Call(String dllName, String functionName, String parameterDescription, int stackSize) {
        this.stackSize = stackSize;
        this.functionName = functionName;
        this.parameterDescription = parameterDescription;
        this.dllName = dllName;
    }
    public int getStackSize() {return stackSize;}
    public String getFunctionName() {return functionName;}
    public String getParameterDescription() {return parameterDescription;}
    public String getDllName() {return dllName;}
}

Puede probar cómo funciona con Virtual Keyboard Commander

Si está escribiendo software de quiosco usando HTML, puede usar las funciones especiales de JavaScript para controlar el teclado en pantalla.

Con JavaScript, puede mostrar, ocultar o mover el teclado. Solo tiene que usar las funciones especiales de JavaScript para agregar información relacionada con el teclado al título del navegador, y la aplicación supervisará el título en busca de cambios.

Descargue el archivo con funciones y ejemplos de JavaScript desde aquí: https://hotvirtualkeyboard.com/commander.html

WM_CSKEYBOARDMOVE: Solución del problema al mover el teclado cuando se usan varias pantallas con diferente DPI.

Por ejemplo, la Pantalla 1 tiene una resolución de 2560x1440 y está configurada en "escala del 125%" en la configuración de pantalla de Windows. La Pantalla 2 es de 1920x1080 y está configurada en "escala del 100%".

Abra la configuración de compatibilidad de aplicaciones de Windows del archivo hvk.exe y establezca el comportamiento de DPI en "Aplicación", lo que significa que la aplicación administra todos los cálculos relacionados con DPI. Con esta configuración activada, puede pasar valores de píxeles físicos a la función de movimiento de su API, y la ventana del teclado se moverá exactamente a esa posición.

Si desea activar este modo de compatibilidad mediante programación (por ejemplo, con su propio instalador), debe establecer la siguiente clave del registro:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers:
"C:\Program Files\HotVirtualKeyboard\hvk.exe"="~ HIGHDPIAWARE"

Esto se aplicará entonces a todos los usuarios. Como alternativa, puede colocar esta clave en el registro para el usuario actual (HKCU).