David Proclaims Solomon King, 1 Kings 1-2.

And the king took an oath and said, “ As the Lord lives, who has redeemed my life from every distress, just as I swore to you by the Lord God of Israel, saying, ‘Assuredly Solomon your son shall be king after me, and he shall sit on my throne in my place,’ so I certainly will do this day.” Then Bathsheba bowed with her face to the earth, and paid homage to the king, and said, “Let my lord King David live forever!” And King David said, “Call to me Zadok the priest, Nathan the prophet, and Benaiah the son of Jehoiada.” So they came before the king. The king also said to them, “Take with you the servants of your lord, and have Solomon my son ride on my own mule, and take him down to Gihon. There let Zadok the priest and Nathan the prophet anoint him king over Israel; and blow the horn, and say, ‘ Long live King Solomon!’ As the Lord has been with my lord the king, even so may He be with Solomon, and make his throne greater than the throne of my lord King David.” Then Zadok the priest took a horn of oil from the tabernacle and anointed Solomon. And they blew the horn, and all the people said, “ Long live King Solomon!”
1 Kings 1:29-34,37,39 - hNKJV