new Text:himessage;
 
public OnGameModeInit()
{
    himessage = TextDrawCreate(1.0, 5.6, "Hi, how are you?"); 
    return 1;
}
 
public OnPlayerConnect(playerid)
{
    new newtext[41], name[MAX_PLAYER_NAME];
    GetPlayerName(playerid, name, MAX_PLAYER_NAME);
    format(newtext, sizeof(newtext), "Hi %s, how are you?", name);
    TextDrawSetString(himessage, newtext);   
    TextDrawShowForPlayer(playerid, himessage);
    return 1;
}

if(Command("/MudarTexto")) return ShowPlayerDialog(playerid, 100, DIALOG_STYLE_INPUT, "TextDraw", "Digite abaixo o texto para a TextDraw", "Alterar", "Cancelar");

public OnDialogResponse(playerid, dialogid, response, listitem, inputtext[])
{
    if(dialogid == 100)
    {
        if(!response) return 1;
        if(!strlen(inputtext)) return ShowPlayerDialog(playerid, 100, DIALOG_STYLE_INPUT, "TextDraw", "Digite abaixo o texto para a TextDraw", "Alterar", "Cancelar");
        TextDrawSetString(TextDraw, inputtext);
    }
    return 1;
}