function showJoin($owner) {
    $form = New-Object System.Windows.Forms.Form
    $form.Owner = $owner
    $form.icon = $icon
    $form.Text = "Unir"
    $form.Width = 445
    $form.Height = 245
    $form.AutoSize = $true
    $form.StartPosition = [System.Windows.Forms.FormStartPosition]::CenterParent
    $form.MaximizeBox = $false
    $form.Font = "Microsoft Sans Serif, 9.35"
    $form.FormBorderStyle = 'FixedDialog'


    $label_ori = New-Object System.Windows.Forms.Label
    $label_ori.Text = "Archivos:"
    $label_ori.AutoSize = $true
    $label_ori.Location = New-Object System.Drawing.Point(20, 23)

    $text_ori = New-Object System.Windows.Forms.TextBox
    $text_ori.Text = $sel_ori
    $text_ori.Width = 250
    $text_ori.Location = New-Object System.Drawing.Point(80, 20)
    $text_ori.add_DoubleClick({
            $text_ori.SelectAll();
        })

    $btn_ori = New-Object System.Windows.Forms.Button
    $btn_ori.Text = "Examinar"
    $btn_ori.AutoSize = $true
    $btn_ori.Location = New-Object System.Drawing.Point(335, 18)
    $btn_ori.Add_Click({    
            $res = selectFile -path "" -formats "Videos (*.*)|*.*" -multi $true
            if ($res -ne $null) {
                $text_ori.Text = ($res -join "::")
                $text_name.Text = "Union ($($res.Length)) - $(Get-Date -Format "yyyy-MM-dd HH.mm")"
            }
        })



    $label_dest = New-Object System.Windows.Forms.Label
    $label_dest.Text = "Destino:"
    $label_dest.AutoSize = $true
    $label_dest.Location = New-Object System.Drawing.Point(20, 58)

    $text_dest = New-Object System.Windows.Forms.TextBox
    $text_dest.Text = $def_dest_dir
    $text_dest.Width = 250
    $text_dest.Location = New-Object System.Drawing.Point(80, 55)
    $text_dest.add_DoubleClick({
            $text_dest.SelectAll();
        })

    $btn_dest = New-Object System.Windows.Forms.Button
    $btn_dest.Text = "Examinar"
    $btn_dest.AutoSize = $true
    $btn_dest.Location = New-Object System.Drawing.Point(335, 53)
    $btn_dest.Add_Click({    
            $dest = selectFolder -path $def_dest_dir
            if ($dest) {
                $text_dest.Text = $dest
            }
        })



    $label_name = New-Object System.Windows.Forms.Label
    $label_name.Text = "Nombre:"
    $label_name.AutoSize = $true
    $label_name.Location = New-Object System.Drawing.Point(20, 93)
    
    $text_name = New-Object System.Windows.Forms.TextBox
    $text_name.Text = ""
    $text_name.Width = 328
    $text_name.Location = New-Object System.Drawing.Point(80, 91)
    $text_name.add_TextChanged({
            removeInvalidChars -textbox $text_name
        })
    $text_name.add_DoubleClick({
            $text_name.SelectAll();
        })
    $text_name.Add_KeyDown({
            if ($_.KeyCode -eq "Enter") {
                $btn_exec.PerformClick()
            }
        })

    $check_encode = New-Object System.Windows.Forms.Checkbox 
    $check_encode.Location = New-Object System.Drawing.Point(80, 127)
    $check_encode.AutoSize = $true
    $check_encode.Text = "Recodificar"
    $check_encode.Checked = $false
    $form.Controls.Add($check_encode)

    $btn_exec = New-Object System.Windows.Forms.Button
    $btn_exec.Text = "Unir"
    $btn_exec.Location = New-Object System.Drawing.Point(140, 160)
    $btn_exec.Width = 150
    $btn_exec.Height = 30
    $btn_exec.Add_Click({   
            try {
                $prevCode = startAlwaysOn
                join -infiles ($text_ori.Text -split "::") -out "$($text_dest.Text)\$($text_name.Text)" -encode $check_encode.Checked
            }
            finally {
                endAlwaysOn -code $prevCode
            }
        })

    $form.Controls.Add($label_ori)
    $form.Controls.Add($text_ori)
    $form.Controls.Add($btn_ori)
    $form.Controls.Add($label_dest)
    $form.Controls.Add($text_dest)
    $form.Controls.Add($btn_dest)
    $form.Controls.Add($label_name)
    $form.Controls.Add($text_name)
    $form.Controls.Add($btn_exec)
    $text_ori.Select()

    $form.Add_Closing({
            $owner.Location = getRelativeLocation -parent $owner -child $form
            $form.Hide()
            $owner.Show()
        })
        
    [PSAppID]::SetAppIdForWindow($form.handle, "$($metadata.package).$app_name")

    $form.Add_LocationChanged({ $global:win_loc = $form.Location })
    $form.Add_Resize({          $global:win_size = $form.Size })

    $form.ShowDialog()
}