我开始制作一个简单的换油应用程序，但我遇到了困难。我不确定这是否是我的逻辑或代码的错误。您将一辆汽车添加到应用程序中，其详细信息将进入数组列表，汽车将显示在主屏幕上的卡片 View 上，显示名称、品牌、型号等。当您从主屏幕上单击汽车时，它会显示在主屏幕上的卡片 View 上。打开另一个屏幕，其中包含汽车和详细信息，其中包含现有机油更换列表和用于添加新机油更换的按钮。添加机油更换后，它会创建另一个列表，其中包含机油更换的详细信息，包括汽车名称。我有它，因此无论您从主屏幕中选择哪辆车，都会显示其自己的机油更换历史记录。我无法弄清楚的问题是，我进行了一个简单的计算，以根据里程显示下一次换油的时间，我希望这个值显示在主屏幕汽车卡上。我可以将一个值传递给卡，但相同的值仍然传递给我列出的每辆车。我不知道如何将里程应得值与正确的汽车联系起来。
添加汽车
EditText addName;
EditText addMake; //from add_car.xml
EditText addModel, addMiles, addOilType, addOilQuarts, addOilFilter, addAirFilter, addPreferredChange;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_car);
addName = findViewById (R.id.txtAddName);
addMake = findViewById (R.id.txtAddMake); //gets whats in txtAddMake from add_car.xml
addModel = findViewById(R.id.txtAddModel);
addMiles = findViewById(R.id.txtAddMiles);
addOilType = findViewById(R.id.txtOilType);
addOilQuarts = findViewById(R.id.txtOilQuarts);
addOilFilter = findViewById(R.id.txtOilFilter);
addAirFilter = findViewById(R.id.txtAirFilter);
addPreferredChange = findViewById(R.id.txtPreferredChange);
Button btnAddCar = findViewById(R.id.btnAddCar);
btnAddCar.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId())
{
case R.id.btnAddCar:
saveCars();
break;
}
}
//calling Cars.java
private void saveCars(){
Cars cars= new Cars(addName.getText().toString(), addMake.getText().toString(), //System.currentTimeMillis() is time of phone, using as name of file
addModel.getText().toString(), addMiles.getText().toString(),addOilType.getText().toString(),
addOilQuarts.getText().toString(),addOilFilter.getText().toString(),addAirFilter.getText().toString(),addPreferredChange.getText().toString());
if( Utilities.saveCars(this,cars)){ //runs savesCars from utilises class
Toast.makeText(this, "Car is saved", Toast.LENGTH_SHORT).show();
finish(); //finish go back to previous actity
}else{
Toast.makeText(this, "error, check storage", Toast.LENGTH_SHORT).show();
}
}
添加换油
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add_oil_change);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
addCurMiles = findViewById(R.id.addOilCurrentMiles);
addCurDate = findViewById(R.id.addOilCurrentDate);
addDueMiles = findViewById(R.id.addOilDueMiles);
addDueDate = findViewById(R.id.addOilDueDate);
addCarName = findViewById(R.id.txtCarName); //passing the filename
btnAddOilChange = findViewById(R.id.btnAddOilChange);
btnAddOilChange.setOnClickListener(this);
btnNxtOilChange = findViewById(R.id.btnNxtOilChange);
btnNxtOilChange.setOnClickListener(this);
SimpleDateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy");
addCurDate.setText(dateFormat.format(new Date()));
Intent i = getIntent();
carFileName = i.getExtras().getString("Car Name");
addCarName.setText(carFileName);
}
@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.btnAddOilChange:
saveOilChange();
break;
case R.id.btnNxtOilChange:
nextOilChange ();
break;
}
}
public void nextOilChange(){
if(addCurMiles.getText().toString() != null) {
int num1 = Integer.parseInt(addCurMiles.getText().toString());
int sum = num1 + 3000;
addDueMiles.setText(Integer.toString(sum));
changeOilMiles = addDueMiles.getText().toString();
}else{
}
}
private void saveOilChange(){OilChange oilChange = new
OilChange(System.currentTimeMillis(),addCurMiles.getText().toString(),
addCurDate.getText().toString(),addDueMiles.getText().toString(),
addDueDate.getText().toString(), addCarName.getText().toString());
//using System.currentTimeMillis(), for file name using .oil as extension
//Write next oil change to main card here!
if( Utilities.saveOilChange(this,oilChange)){
setResult(RESULT_OK);
finish(); //finish go back to previous activity
}else{
Toast.makeText(this, "error, check storage", Toast.LENGTH_SHORT).show();
}
}
我在汽车卡上填写换油信息，但它适用于所有汽车
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent
data) {
// TODO Auto-generated method stub
Toast.makeText(this, "hello", Toast.LENGTH_SHORT).show();
txtOilChangeDue.setText(AddOilChange.changeOilMiles);
}
点击汽车时显示汽车卡并打开新 Activity
//this populates the list view
@Override
protected void onResume() {
super.onResume();
main_car_list.setAdapter(null);
cars = Utilities.getAllSavedCars(this);
//for context menu
registerForContextMenu(main_car_list);
if(cars == null || cars.size() == 0){
Toast.makeText(this,"you have no cars added",
Toast.LENGTH_SHORT).show();
return;
}else{
ca = new CarAdapter(this, R.layout.car_list, cars);
main_car_list.setAdapter(ca);
//when click item(car) opens new activity
main_car_list.setOnItemClickListener(new
AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view,
int position, long l) { //tabbed automatically filled in this
String fileName =
((Cars)main_car_list.getItemAtPosition(position)).getName() +
Utilities.FILE_EXTENSION; //gets filename
Intent viewCar = new
Intent(getApplicationContext(),CarDetails.class); //when clicked on item
in list opens deails
//this is how pass data between activities
// this passes car name and model to CarDetails
viewCar.putExtra("Car_File", fileName);
startActivity(viewCar);
}
});
}
}
**请添加您的适配器类
汽车适配器类
public class CarAdapter extends ArrayAdapter<Cars> {
public CarAdapter(Context context, int resource, ArrayList<Cars> cars) {
super(context, resource, cars);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// return super.getDropDownView(position, convertView, parent);
if(convertView == null){
convertView = LayoutInflater.from(getContext())
.inflate(R.layout.car_list, null); //car_list xml
}
Cars cars = getItem(position);
if(cars != null){
TextView txtName = convertView.findViewById(R.id.txtName);
TextView txtMake = convertView.findViewById(R.id.txtMake); //from car_list reads what's there (i think)
TextView txtModel =convertView.findViewById(R.id.txtModel);
TextView txtMiles = convertView.findViewById(R.id.txtMiles);
TextView txtOilChangeDue = convertView.findViewById(R.id.txtOilChangeDue);
// TextView txtOilChangeDueMiles = convertView.findViewById(R.id.txtOilChangeDueMileage);
txtName.setText(cars.getName());
txtMake.setText(cars.getMake());
txtModel.setText(cars.getModel());
txtMiles.setText(cars.getMiles());
txtOilChangeDue.setText(AddOilChange.changeOilMiles); //replaces value each time and on both/all cars
//txtOilChangeDue.setText("hi"); works
// txtDueMileage.setText(cars.getDueMileage());
// txtDate.setText(cars.getDateTimeFormatted(getContext())); //not sure what for
}
return convertView;
}
}
油适配器类
public class OilAdapter extends ArrayAdapter <OilChange> {
public OilAdapter(Context context, int resource, List<OilChange> oilchange) { //use ctrl+insert to add this change object to oilchange
super(context, resource, oilchange); //had list changed to ArrayList (didnt seem to make a difference)
}
@Override
public View getView(int position, View convertView, ViewGroup parent) { //use ctrl+o to add overide choose getView
// return super.getView(position, convertView, parent); //not sure why i have to comment out
if (convertView == null){
convertView = LayoutInflater.from(getContext()).inflate(R.layout.oil_change_records,null); //layout should (in this case) be card view list
} //this just calls list below will populate it
OilChange oc = getItem(position); //oc - any name u want , position - gets items out of list(i think)
if(oc != null){
TextView cDate = convertView.findViewById(R.id.txtOilRecDate); //gets text views from oil change records list
TextView cMiles = convertView.findViewById(R.id.txtOilRecMiles);
cDate.setText(oc.getCurDate()); //this sets the current date and miles from info just added for the oil change
cMiles.setText(oc.getDueMiles());
}
//getting last record
if(position==getCount()-1)
{
}
return convertView;
}
}
最佳答案
我之前已经经历过这个，并且从上面的代码中，在 CarAdapter 中，您提供了一个常量 AddOilChange.changeOilMiles 这就是为什么值是相同的
txtOilChangeDue.setText(AddOilChange.changeOilMiles);
解决方案:
1) 在 Car 模型中创建一个额外字段
private String changeOil;
........
//create setter and getter for changeOil
然后获取当前需要更新的汽车，更新汽车的changeOil，同时保存添加换油中的oilChange
2) 将 OilChange 数组列表传递给 CarAdapter
ArrayList<OilChange> oliChanges;
public CarAdapter(Context context, int resource, ArrayList<Cars> cars, ArrayList<OilChange> oilChanges) {
super(context, resource, cars);
this.oilChanges = oilChanges;
}
..........
Cars cars = getItem(position);
OilChange oilChange = oilChanges.get(position);
if(cars != null){
TextView txtName = convertView.findViewById(R.id.txtName);
TextView txtMake = convertView.findViewById(R.id.txtMake); //from car_list reads what's there (i think)
TextView txtModel =convertView.findViewById(R.id.txtModel);
TextView txtMiles = convertView.findViewById(R.id.txtMiles);
TextView txtOilChangeDue = convertView.findViewById(R.id.txtOilChangeDue);
// TextView txtOilChangeDueMiles = convertView.findViewById(R.id.txtOilChangeDueMileage);
txtName.setText(cars.getName());
txtMake.setText(cars.getMake());
txtModel.setText(cars.getModel());
txtMiles.setText(cars.getMiles());
//obtain the oilchange from the model ensure you have created a getOilChange() method in OilChange class to obtain the oilchange
txtOilChangeDue.setText(oilChange.getOilChange()); //replaces value each time and on both/all cars
关于java - 如何根据另一个数组列表从一个数组列表填充 EditText，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/57714111/