如何将Onclick侦听器设置为动态微调器项目

Question

I have three spinners (1.Vehicle make, 2.Vehicle Type, 3.Model). Vehicle make having only option "2 Wheeler","4 Wheeler".

What i did, If i choosed anyone option from vehicle make means shows only that type of vehicle type(For ex: If i choose 2 Wheeler means Vehicle Type shows Bajaj,Honda etc., like this).

I want, If i choose anyone option from vehicle type means show that type of model in third spinner.

I dont know how to access/change third spinner when second spinner selected.

Please anyone help me!

My code here:

 public class VehicleFragment extends Fragment { Spinner vehicleType; Spinner vehicleMake; Spinner model; String[] vehicleItems = {"Please Choose Vehicle Type","2 Wheeler","4 Wheeler"}; @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_layout_vehicle, container, false); vehicleType = (Spinner)view.findViewById(R.id.veh_typeSpinner); vehicleMake = (Spinner)view.findViewById(R.id.makeSpinner); model = (Spinner)view.findViewById(R.id.modelSpinner); //VehicleType adapter ArrayAdapter vehicleAdapter = new ArrayAdapter(this.getActivity(),android.R.layout.simple_spinner_item,vehicleItems); vehicleAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); vehicleType.setAdapter(vehicleAdapter); vehicleType.setOnItemSelectedListener(new VehiclTypeSelectedListener()); return view; } public class VehiclTypeSelectedListener implements AdapterView.OnItemSelectedListener { @Override public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { String item = parent.getItemAtPosition(position).toString(); if (item == "2 Wheeler"){ addItemOnVehicleMake(); } else if (item == "4 Wheeler"){ addItemOnFourVehicleMake(); } } @Override public void onNothingSelected(AdapterView<?> parent) { } } public void addItemOnVehicleMake(){ vehicleMake = (Spinner) getActivity().findViewById(R.id.makeSpinner); String[] myState = getResources().getStringArray(R.array.twoWheeler_make); List<String> makeArrayList = Arrays.asList(myState); ArrayAdapter dataAdapter = new ArrayAdapter(this.getActivity(), android.R.layout.simple_spinner_item, makeArrayList); dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); vehicleMake.setAdapter(dataAdapter); } public void addItemOnFourVehicleMake(){ vehicleMake = (Spinner) getActivity().findViewById(R.id.makeSpinner); String[] myState = getResources().getStringArray(R.array.fourWheeler_make); List<String> makeArrayList = Arrays.asList(myState); ArrayAdapter dataAdapter = new ArrayAdapter(this.getActivity(), android.R.layout.simple_spinner_item, makeArrayList); dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); vehicleMake.setAdapter(dataAdapter); } } 

Thanks in advance!!

Answer 1

获取布局的子级并检查微调框的实例，然后设置onClick侦听器。

Answer 2

When addItemOnVehicleMake() method called, at that time suppose "vehicleMake" spinner has vehicle make companies like,

        Bajaj, 
        Honda,
        .
        . etc,

and inside addItemOnFourVehicleMake() method 4-wheeler has,

        Honda,
        Ford,
        .
        .. etc.

When populate spinner it always set first value from list by default unless we set different item position manually.

If two wheeler has set Bajaj, get list of models of Bajaj and populate spinner of "VehicleMake" inside addItemOnVehicleMake() for the first item only.

            public void addItemOnVehicleMake()
            {
               ...
               ... 
               // code here to bind model spinner and set default "0" position item.
               model.setSelection(0);
            }

    Also write down the VehicleMake spinner item select listener method,to populate the "VehicleModel" spinner based on selected item in "VehicleMake" spinner.

    vehicleMake.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
                        @Override
                        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

                            //Here is the code to populate model spinner.
                        }

                        @Override
                        public void onNothingSelected(AdapterView<?> parent) {

                        }
                    });

Answer 3

You need to populate your spinner at the time when say you choose "2 Wheeler". For this you need to have data sets of vehicles that are 2 wheelers and a separate dataset for vehicles that are say 4 wheelers. So basically in your addItemOnVehicleMake(String s) method, send your item string to this method:

public void addItemOnFourVehicleMake(String vehicleType){
    if(vehicleType == "4 Wheeler"){
   //add dataset to spinner that shows only 4 wheelers.
}
else if(vehicleType == "2 Wheeler"){
   //add dataset to spinner that shows only 2 wheelers.
}
//and so on....
}