Dartlang: How to get key and values from json? - json

Question

I'm having a little problem and couldn't figure it out. I created a table with checkbox and it's working and can save to json without a problem. Now i wanna make my checkboxes have their default values set from json data when the page loads (to make it easier to edit). Anyway here is my code:
//row index
var index = 0;
//gets full info of student
var responseStudent = rpc.call('db.findOne', ['StudentAnket', {
'_id': '${this.objId}'
}]);
result = responseStudent['result'];
//gets info needed for my table
//{anket: true, request: true, statement: false, etc...}
var resultMat = result['listmaterial'];
//materials is a list which contains id, name of rows
materials.forEach((m) {
//creating table body
index = index + 1;
tbody.append(new Element.tr()
..append(new TableCellElement()..text = index.toString())
..append(new TableCellElement()..append(new LabelElement()
..text = m['name']
..setAttribute('for', m['id'])))
..append(new TableCellElement()..append(new InputElement()
..id = m['id']
..type = "checkbox"
..checked = "VALUE TAKEN FROM JSON")));
});
So how can i get keys and values from resultMat and set checked property for each checkbox?
Edit:
List materials = [{
'id': 'anket',
'name': 'Student anket'
}, {
'id': 'request',
'name': 'Request'
}, {
'id': 'statement',
'name': 'Statement'
}, {
'id': 'marklist',
'name': 'Mark List'
}];

Answer 1

Your information how your materials structure looks like is not clear. A List has only one value not two ('id, 'name of rows'). First you have to ensure that your JSON is not a String but a Dart data structure (Lists, Maps, values).
You can take a look at the answers to this questions to learn how this works
Dart Parse JSON into Table
Then you should be able to access the value like
..checked = resultMat[m['id']] ;