I want a dropdown of (Selectable) predictions to appear below while I type in a text field of Tasks module. I know how to change dropdown values of a dropdown field from database values but user can’t input new value into the dropdown field(Only can select). I want the user to be able to type entry into text field as usual with clickable suggestions of the entered text below like a dropdown. I am new to SuiteCRM so file paths would be really helpful.
Instead of a Dropdown defined in Admin / Dropdown editor, try a separate module done in Module builder, and add each option value as a separate record.
Now connect that custom module to your original Tasks module using a Relate field.
Relate field already have that find-as-you-type behaviour by default.
What you are trying to achieve can be accomplished by integrating jQuery Autocomplete in the Edit view of tasks.
In editviewdefs.php you can make your field as customCode and in your custom JS, you can trigger the autocomplete on change of your text field.
This may help you. Here you cannot type on the text box and have a suggestion box. But this add-on allows you to add new value in Dropdown from Editview itself. So your user can add new value if they don’t find in dropdown.