input data codeigniter always 0 on database - php

Question

I am new to CodeIgniter. I found the problem.
I have read on CodeIgniter Form always sends '0' data and Zero (0 ) Database Result in Codeigniter but it did not help.
the problem data in the database is always 0.
my add view code
<form method="post">
<div class="form-inline form-group">
<label for="kegiatan">Kegiatan : </label>
<select class="form-control" id="disableSelect" disabled><option>MPAB</option></select> <!-- inget ganti pake id terakhir -->
</div>
<div class="form-group">
<label for="indikator">Indikator : </label>
<input type="text" name="indikator" id="indikator" placeholder="Indikator" class="form-control"> <!-- kosongin, tapi kalo edit munculin indikator yang di edit -->
</div>
<div class="form-group">
<span class='glyphicon glyphicon-plus'></span> add
</div>
</form>
my controller
public function addIpMpabDb() {
if ($this->form_validation->run()==true){
$tambah = array (
'indikator' =>$this->input->post('indikator'),
'id_jk'=>1
);
$this->tb_det_penilaian->addIndikator($tambah);
redirect("ipmpab");
}
my model
function addIndikator($tambah)
{
$this->db->insert('tb_det_penilaian', $tambah);
}

Answer 1

You don't have a valid submit button in your html code.
Remove your link and use an input type "submit" or a button
Replace :
<div class="form-group">
<a href="<?= base_url() ?>ipmpab/addIpMpabDb/" class="btn btn-success">
<span class='glyphicon glyphicon-plus'></span> add
</a>
</div>
With :
<div class="form-group">
<button type="submit" class="btn btn-success">
<span class='glyphicon glyphicon-plus'></span>add
</button>
</div>
... For exemple
Then add the action attribute to the form :
<form method="post" action="<?= site_url('ipmpab/addIpMpabDb'); ?>">