Unity虚拟键盘

这是一个网上找的插件，自己改了点东西，方便使用在项目中。暂时不适用中文输入，中文输入可能得调出系统输入法，项目不需要就没去研究了，大伙有兴趣可以研究研究。

包含两个类，一个是虚拟键盘类，还一个是文本框输入类。下面直接上代码：

using UnityEngine;
using System.Collections.Generic;

/*
 * On Screen Keyboard
 * By Richard Taylor, Holopoint Interactive Pty. Ltd.
 * 
 * FEATURES:
 * - Fully configurable layout
 * - Fully skinnable
 * - Key select and press audio
 * - Configurable caps functionality
 * - Configurable key repeat settings
 * - Works with both joystick/gamepad and mouse/touchscreen input
 * - Simple integration
 * - Tested using Xbox 360 controller and iPad
 */


/*
 *  Time list:
 *      June于2020.04.17改
 *      
 */

public enum ShiftState { Off, Shift, CapsLock }

public class OnScreenKeyboard : MonoBehaviour {
	
	// INSPECTOR VISIBLE PROPERTIES -------------------------------------------
	
	// Skinning
	public GUIStyle boardStyle;
	public GUIStyle keyStyle;
	public Texture2D selectionImage;
	
	// Board and button sizes
	public Rect screenRect = new Rect(0, 0, 0, 0);
    public Vector2 stdKeySize = new Vector2(32, 32);
    public Vector2 lgeKeySize = new Vector2(64, 32);
	
	// Key audio
	public AudioClip keySelectSound = null;
	public AudioClip keyPressSound = null;
	
	// Shift settings
	public bool shiftStateSwitchEnabled = true;
	public ShiftState shiftStateDefault = ShiftState.Off;
	
	// Joystick settings
	public bool joystickEnabled = true;
	public string joyPressButton = "Fire1";
	public string joyCapsButton = "Fire2";
	
	// Our keys. By default we'll include a simplified QWERTY keyboard handy 
	// for name entry, but this can literally be anything you want. Either the 
	// two arrays must be of matching length, or lowerKeys must be of size 0.
    public string[] upperKeys = { "Q", "W", "E", "R", "T", "Y", "U", "I", "O", "P", "<<", "", 
                                    "A", "S", "D", "F", "G", "H", "J", "K", "L", "Done", "", 
                                    "Z", "X", "C", "V", "B", "N", "M", "Caps", "Space" };

    public string[] lowerKeys = { "q", "w", "e", "r", "t", "y", "u", "i", "o", "p", "<<", "", 
                                    "a", "s", "d", "f", "g", "h", "j", "k", "l", "Done", "", 
                                    "z", "x", "c", "v", "b", "n", "m", "Caps", "Space" };

	// The size must match the number of rows, or be 0
    public float[] rowIndents = { 0.0f, 0.2f, 0.5f };
	
	// Delays for repeated events
	public float initialRepeatDelay = 0.8f;
	public float continuedRepeatDelay = 0.2f;
	public float moveRepeatDelay = 0.3f;
	
	
	// INTERNAL DATA MEMBERS --------------------------------------------------
	private string keyPressed = "";
	private int pSelectedButton;
	
	private GUIStyle pressedStyle = null;
	
	private float keyRepeatTimer = 0;
	private bool keyDownPrevFrame = false;
	private bool keyReleased = false;
	private bool lastKeyWasShift = false;
	
	private float moveTimer = 0;
	
	private ShiftState shiftState;

    private bool[] keySizes;
    private Rect[] keyRects;
    private int[] rowMarkers;

	private int selectedButton;
	
	private AudioSource keySelectSource = null;
	private AudioSource keyPressSource = null;
	
	// Change this if it's conflicting with your own GUI's windows
	private int windowId = 0;


    /// 

    /// 新增属性，控制虚拟键盘在屏幕中的位置
    /// 
    [Header("June_Add_Attribute_Control_keyBoardTF---------------------------------------")]
    public float _keyBoardTF_X;
    public float _keyBoardTF_Y;



    // INITIALISATION ---------------------------------------------------------
    void Awake()
	{
        // Check that our key array sizes match
		if (upperKeys.Length != lowerKeys.Length && !(lowerKeys.Length == 0 && !shiftStateSwitchEnabled))
		{
			print("Error: OnScreenKeyboard needs the same number of upper and lower case keys, or there must be no lower keys and caps switch must be disabled");
			Destroy(this);
		}

        // Check for row markers and count row lengths
        List rowMarkersTemp = new List();
        for (int i = 0; i < upperKeys.Length; i++) 
			if (upperKeys[i] == "") rowMarkersTemp.Add(i);
        rowMarkers = rowMarkersTemp.ToArray();

        // Check row indents
        if (rowIndents.Length < rowMarkers.Length + 1)
        {
            float[] rowIndentsTemp = new float[rowMarkers.Length + 1];
            for (int i = 0; i < rowIndentsTemp.Length; i++)
            {
                if (i < rowIndents.Length) rowIndentsTemp[i] = rowIndents[i];
                else rowIndentsTemp[i] = 0;
            }
        }

        // Check button sizes - anything that's not a single character is a "large" key
        keySizes = new bool[upperKeys.Length];
        for (int i = 0; i < upperKeys.Length; i++) keySizes[i] = upperKeys[i].Length > 1;

        // Populate the array of key rectangles
        keyRects = new Rect[upperKeys.Length];
        int currentRow = 0;
        float xPos = (rowIndents.Length > 0 ? rowIndents[currentRow] : 0) + stdKeySize.x*0.33f;
        float yPos = stdKeySize.y*1.33f*currentRow + stdKeySize.y*0.33f;
        for (int i = 0; i < upperKeys.Length; i++)
		{
			// On the start of a new line, position the new key accordingly
            if (IsRowMarker(i))
            {
                if (i != 0) currentRow++;
                xPos = (rowIndents.Length > 0 ? rowIndents[currentRow] : 0) + stdKeySize.x * 0.33f;
                yPos = stdKeySize.y*1.33f*currentRow + stdKeySize.y * 0.33f;
            }
            else
            {
                // Draw the key, and set keyPressed accordingly
                keyRects[i] = new Rect(screenRect.x + xPos, screenRect.y + yPos, keySizes[i] ? lgeKeySize.x : stdKeySize.x, keySizes[i] ? lgeKeySize.y : stdKeySize.y);

                // Move over to the next key's position on this line
                xPos += keySizes[i] ? lgeKeySize.x + stdKeySize.x*0.33f : stdKeySize.x*1.33f;
            }
		}

        // Put ourselves in a default screen position if we haven't been explicitly placed yet
        if (screenRect.x == 0 && screenRect.y == 0 && screenRect.width == 0 && screenRect.height == 0)
        {
            // Figure out how big we need to be
            float maxWidth = 0;
			float maxHeight = 0;
			for (int i = 0; i < keyRects.Length; i++)
			{
				if (keyRects[i].xMax > maxWidth) maxWidth = keyRects[i].xMax;
				if (keyRects[i].yMax > maxHeight) maxHeight = keyRects[i].yMax;
			}
			maxWidth += stdKeySize.x*0.33f;
			maxHeight += stdKeySize.y*0.33f;
				
            screenRect = new Rect(_keyBoardTF_X, _keyBoardTF_Y, maxWidth, maxHeight);
        }
		
		// If we've got audio, create sources so we can play it
		if (keySelectSound != null)
		{
			keySelectSource = gameObject.AddComponent() as AudioSource;
			keySelectSource.spatialBlend = 0;
			keySelectSource.clip = keySelectSound;
		}
		if (keyPressSound != null)
		{
			keyPressSource = gameObject.AddComponent() as AudioSource;
			keyPressSource.spatialBlend = 0;
			keyPressSource.clip = keyPressSound;
		}
		
		// Set the initial shift state
		if (shiftStateSwitchEnabled) SetShiftState(shiftStateDefault);
		
		// Create a pressed button skin for joysticks
		pressedStyle = new GUIStyle();
		pressedStyle.normal.background = keyStyle.active.background;
		pressedStyle.border = keyStyle.border;
		pressedStyle.normal.textColor = keyStyle.active.textColor;
		pressedStyle.alignment = keyStyle.alignment;
        //新增字体样式------->按钮按下的时候调用
        pressedStyle.font = keyStyle.font;

    }


    // GAME LOOP --------------------------------------------------------------

    void Update() 
	{
		// Handle keys being released
		if (!keyDownPrevFrame) 
		{
			keyRepeatTimer = 0;
			if (!keyReleased) KeyReleased();
		}
		keyDownPrevFrame = false;
		
		// Check mouse input
		Vector3 guiMousePos = Input.mousePosition;
		guiMousePos.y = Screen.height - guiMousePos.y;
		for (int i = 0; i < keyRects.Length; i++)
		{
			Rect clickRect = keyRects[i];
			clickRect.x += screenRect.x; clickRect.y += screenRect.y;
			// Check for the click ourself, because we want to do it differently to usual
			if (clickRect.Contains(guiMousePos)) 
			{
				selectedButton = i;
				if (Input.GetMouseButtonDown(0)) KeyPressed();	
				else if (Input.GetMouseButton(0)) KeyHeld();
				else if (Input.GetMouseButtonUp(0)) KeyReleased();
			}
		}
		
		// If the joystick is in use, update accordingly
        if (joystickEnabled) CheckJoystickInput();
	}

    private void CheckJoystickInput()
    {	
        // KEY SELECTION		
        float horiz = Input.GetAxis("Horizontal");
        float vert = Input.GetAxis("Vertical");
		
		moveTimer -= Time.deltaTime;
		if (moveTimer < 0) moveTimer = 0;
		
		bool hadInput = false;
		bool moved = false;
        if (horiz > 0.5f)
		{
			if (moveTimer <= 0) 
			{
				SelectRight();
				moved = true;
			}
			hadInput = true;
		}
        else if (horiz < -0.5f)
		{
			if (moveTimer <= 0) 
			{
				SelectLeft();
				moved = true;
			}
			hadInput = true;
		}
        if (vert < -0.5f)
		{
			if (moveTimer <= 0) 
			{
				SelectDown();
				moved = true;
			}
			hadInput = true;
		}
        else if (vert > 0.5f)
		{
			if (moveTimer <= 0) 
			{
				SelectUp();
				moved = true;
			}
			hadInput = true; 
		}
		if (!hadInput) moveTimer = 0;
		if (moved) 
		{
			moveTimer += moveRepeatDelay;
			if (keySelectSource != null) keySelectSource.Play();
		}
        selectedButton = Mathf.Clamp(selectedButton, 0, upperKeys.Length - 1);

        // CAPITALS
        if (shiftStateSwitchEnabled &&
            (Input.GetKeyDown(KeyCode.LeftShift) ||
            Input.GetButtonDown(joyCapsButton)))
            shiftState = (shiftState == ShiftState.CapsLock ? ShiftState.Off : ShiftState.CapsLock);

        // TYPING
        if (Input.GetButtonDown(joyPressButton)) KeyPressed();
		else if (Input.GetButton(joyPressButton)) KeyHeld();
    }
	
	// Called on the first frame where a new key is pressed
	private void KeyPressed()
	{
		keyPressed = (shiftState != ShiftState.Off) ? upperKeys[selectedButton] : lowerKeys[selectedButton];
		pSelectedButton = selectedButton;
		keyRepeatTimer = initialRepeatDelay;
		
		keyDownPrevFrame = true;
		keyReleased = false;
		lastKeyWasShift = false;
		
		if (keyPressSource != null) keyPressSource.Play();
	}
	
	// Called for every frame AFTER the first while a key is being held
	private void KeyHeld()
	{
		// If the key being pressed has changed, revert to an initial press
		if (selectedButton != pSelectedButton)
		{
			KeyReleased();
			KeyPressed();
			return;
		}
		
		// Check if we're ready to report another press yet
		keyRepeatTimer -= Time.deltaTime;
		if (keyRepeatTimer < 0)
		{
			keyPressed = (shiftState != ShiftState.Off) ? upperKeys[selectedButton] : lowerKeys[selectedButton];
			keyRepeatTimer += continuedRepeatDelay;	
			
			if (keyPressSource != null) keyPressSource.Play();
		}
		
		keyDownPrevFrame = true;
		keyReleased = false;
	}
	
	// Called the frame after a key is released
	private void KeyReleased()
	{
		keyDownPrevFrame = false;
		keyReleased = true;
		
		if (shiftState == ShiftState.Shift && !lastKeyWasShift)
			SetShiftState(ShiftState.Off);
	}
	
	// Selects the key to the left of the currently selected key
    private void SelectLeft()
    {
        selectedButton--;
		
        // If we've hit the start of a row, wrap to the end of it instead
        if (IsRowMarker(selectedButton) || selectedButton < 0)
        {
            selectedButton++;
            while (!IsRowMarker(selectedButton+1) && selectedButton+1 < upperKeys.Length) selectedButton++;
        }
    }
	
	// Selects the key to the right of the currently selected key
    private void SelectRight()
    {
        selectedButton++;
		
        // If we've hit the end of a row, wrap to the start of it instead
        if (IsRowMarker(selectedButton) || selectedButton >= upperKeys.Length)
        {
            selectedButton--;
            while (!IsRowMarker(selectedButton-1) && selectedButton-1 >= 0) selectedButton--;
        }
    }
	
	// Selects the key above the currently selected key
    private void SelectUp()
    {
		// Find the center of the currently selected button
		float selCenter = keyRects[selectedButton].x + keyRects[selectedButton].width/2;
		
		// Find the start of the next button;
		int tgtButton = selectedButton;
		while (!IsRowMarker(tgtButton) && tgtButton >= 0) tgtButton--;
		if (IsRowMarker(tgtButton)) tgtButton--;
		if (tgtButton < 0) tgtButton = upperKeys.Length-1;
		
		// Find the button with the closest center on that line
		float nDist = float.MaxValue;
		while (!IsRowMarker(tgtButton) && tgtButton >= 0)
		{
			float tgtCenter = keyRects[tgtButton].x + keyRects[tgtButton].width/2;
			float tDist = Mathf.Abs(tgtCenter - selCenter);
			if (tDist < nDist) 
			{
				nDist = tDist;
			}
			else 
			{
				selectedButton = tgtButton+1;	
				return;
			}
			tgtButton--;
		}
		selectedButton = tgtButton+1;
    }
	
	// Selects the key below the currently selected key
    private void SelectDown()
    {
		// Find the center of the currently selected button
		float selCenter = keyRects[selectedButton].x + keyRects[selectedButton].width/2;
		
		// Find the start of the next button;
		int tgtButton = selectedButton;
		while (!IsRowMarker(tgtButton) && tgtButton < upperKeys.Length) tgtButton++;
		if (IsRowMarker(tgtButton)) tgtButton++;
		if (tgtButton >= upperKeys.Length) tgtButton = 0;
		
		// Find the button with the closest center on that line
		float nDist = float.MaxValue;
		while (!IsRowMarker(tgtButton) && tgtButton < upperKeys.Length)
		{
			float tgtCenter = keyRects[tgtButton].x + keyRects[tgtButton].width/2;
			float tDist = Mathf.Abs(tgtCenter - selCenter);
			if (tDist < nDist) 
			{
				nDist = tDist;
			}
			else 
			{
				selectedButton = tgtButton-1;	
				return;
			}
			tgtButton++;
		}
		selectedButton = tgtButton-1;
    }

    // Returns the row number of a specified button
    private int ButtonRow(int buttonIndex)
    {
        for (int i = 0; i < rowMarkers.Length; i++)
            if (buttonIndex < rowMarkers[i]) return i;
		
        return rowMarkers.Length;
    }
	
	
    // GUI FUNCTIONALITY ------------------------------------------------------
	
    void OnGUI() 
	{	
		GUI.Window(windowId, screenRect, WindowFunc, "", boardStyle);
	}
	
	private void WindowFunc(int id)
	{
		for (int i = 0; i < upperKeys.Length; i++)
		{
            if (!IsRowMarker(i))
            {
                // Draw a glow behind the selected button
                if (i == selectedButton)
                    GUI.DrawTexture(new Rect(keyRects[i].x-5, keyRects[i].y-5, keyRects[i].width+10, keyRects[i].height+10), selectionImage);
                // Draw the key
				// Note that we don't do click detection here, we do it in update
				GUI.Button(keyRects[i], (shiftState != ShiftState.Off) ? upperKeys[i] : lowerKeys[i], 
				           (joystickEnabled && selectedButton == i && Input.GetButton(joyPressButton) ? pressedStyle : keyStyle));
            }
		}
	}
	
	// Returns true if they item at a specified index is a row end marker
    private bool IsRowMarker(int currentKeyIndex)
    {
        for (int i = 0; i < rowMarkers.Length; i++) if (rowMarkers[i] == currentKeyIndex) return true;
        return false;
    }

	
    // CONTROL INTERFACE ------------------------------------------------------

    // Returns the latest key to be pressed, or null if no new key was pressed 
    // since last time you checked. This means that you can only grab a single 
    // keypress once, as it's cleared once you've read it. It also means that 
    // if you let the user press multiple keys between checks only the most 
    // recent one will be picked up each time.
    public string GetKeyPressed() 
	{
		if (keyPressed == null) keyPressed = "";
		
		string key = keyPressed;
		keyPressed = "";
		return key; 
	}
	
	// Toggle the caps state from elsewhere
	public void SetShiftState(ShiftState newShiftState)
	{
		if (!shiftStateSwitchEnabled) return;
			
		shiftState = newShiftState;
		if (shiftState == ShiftState.Shift) lastKeyWasShift = true;
	}
	
	public ShiftState GetShiftState() { return shiftState; }
}

using UnityEngine;
using UnityEngine.UI;


/// 

/// 这是虚拟键盘插件脚本，June于2020.4.16改
/// 


public class OnScreenKeyboardExample : MonoBehaviour 
{
	public OnScreenKeyboard osk;
	/// 

    /// 输入文字
    /// 
	private string _inputString;
    /// 

    /// 输入文本框
    /// 
    public InputField _inputField;

    //每次激活清空文本框内容
    private void OnEnable()
    {
        _inputString = "";
    }

    void Update () 
    {
		
		// You can use input from the OSK just by asking for the most recent 
		// pressed key, which will be returned to you as a string, or null if 
		// no key has been pressed since you last checked. Note that if more 
		// than one key has been pressed you will only be given the most recent.
		string keyPressed = osk.GetKeyPressed();
		if (keyPressed != "")
		{
            
			// Take different action depending on what key was pressed
			if (keyPressed == "Backspace" || keyPressed == "<<")
			{
				// Remove a character
				if (_inputString.Length > 0)
                    _inputString = _inputString.Substring(0, _inputString.Length-1);
			}
			else if (keyPressed == "Space")
			{
                // Add a space
                _inputString += " ";
            }
			else if (keyPressed == "Enter" || keyPressed == "Done")
			{
                // Change screens, or do whatever you want to 
                // do when your user has finished typing :-)
            }
			else if (keyPressed == "Caps")
			{
				// Toggle the capslock state yourself
				osk.SetShiftState(osk.GetShiftState() == ShiftState.CapsLock ? ShiftState.Off : ShiftState.CapsLock);
            }
			else if (keyPressed == "Shift")
			{
				// Toggle shift state ourselves
				osk.SetShiftState(osk.GetShiftState() == ShiftState.Shift ? ShiftState.Off : ShiftState.Shift);
            }
			else
			{
                //限制输入
                if (_inputField.text.Length >= _inputField.characterLimit) return;
                // Add a letter to the existing string
                _inputString += keyPressed;
			}
            //将文字赋值给文本框中的文本属性
            _inputField.text = _inputString;

        }
	}
}

在场景中新建个空物体，用来放虚拟键盘脚本，再新建个输入文本框，脚本可以挂在画布上或者新建个空物体都行。把输入文本框赋上去就可以了。运行效果是这样的

当然，你想要各种风格之类的，换底图之类的，以及按键数量，都可以自行设置。

详情待补充......