How do i make character jump in SDL?

[Nano511]

When i press 'w' the character flies up.

Player.cpp

void Player::HandleEvents( SDL_Event event )
{
	if( event.type == SDL_KEYDOWN )
	{
		switch( event.key.keysym.sym )
		{

		case SDLK_w:
			if( !jumping )
				jumping = true;
		}
	}

	if( jumping )
	{
		yVel	-= gravity;
		gravity += 2;

		if( yPos <= MAX_JUMP_HEIGHT )
		{
			yVel += gravity;
			gravity -= 2;
			jumping = false;
		}	
        }
	else
	{
		yVel += 2;
	}
}

bool Player::CollisionWithGround()
{
	if( yVel > 0 )
	{
		return true;
	}

	return false;
}

And in Game.cpp

void Game::Logic()
{
        //Collision with floor
	if( player.CollisionWithGround() )
	{
		player.yVel -= 1;
		player.jumping = false;
	}

        player.yPos += player.yVel;
}