Unity自定义按键二段跳

Unity 创建andoird游戏，自建了一个透明的屏幕按键“JumpButton”， 如何实现这个按键的二段跳

Rigidbody2D rb;
private BoxCollider2D coll;
private SpriteRenderer sprite;
private Animator anim;

public Joystick joystick;

[SerializeField] private LayerMask jumpableGround;

private float dirX = 0f; 
[SerializeField] private float moveSpeed = 10f;
[SerializeField] private float jumpForce = 16f;

private int m_jumpTimes;
bool doubleJump;

public void JumpButton()
{
if (rb.velocity.y == 0)
{
if (IsGrounded())
{

            rb.velocity = Vector2.up * jumpForce;
            doubleJump = true;
            //rb.velocity = new Vector3(rb.velocity.x, jumpForce);  
        }
        else if (doubleJump)
        {
            rb.velocity = Vector2.up * jumpForce;
            doubleJump = false;
        }
    }
    UpdateAnimationUpdate();
}

你应该定义一个全局变量用来计数的，控制你可以跳的次数，跳第一次时计数+1；再跳一次重置为0试试