@hakuna
First of all you need a post:
//...
BufDatasetStudies.Post; //this line
DataSourceStudies.DataSet:= BufDatasetStudies;
Secondly the field definitions are wrong. Please do the following:
1. Double click the BufDataset, select all , then click the "-" button
2. Press the "Create New field and..."(third from left), select FieldType = Data, enter a name, then select a propert type: string, integer, float, date whatever
3. Go to grid columns, then press the "Add fields" button
4. From code, add the values like this:
with BufDatasetStudies do
begin
Append;
IDStudy.AsString := AvoidNull(Study.Value.Items[0].Value);
RegistrationDate.AsDateTime:= AvoidNull(Study.Value.Items[1].Value);
//...
Age.AsInteger := AvoidNull(Study.Value.Items[4].Value);
Post;
end;
PS: If it's not working just attach a test project + a demo json. Some forum users lately likes to play the guessing game. We don't.
PS1: Did you code in c, c# in the past? How you typed those field declaration suggest that you came from a c background.