我已经在网上搜索了，找不到解决方案。
我要执行的操作是在第二个微调器中显示数组的列表，具体取决于第一个微调器中的选定选项。
逻辑将是这样的： 如果第一个微调器= CSE / IT
然后，第二个微调选项将是： 1. BCA 2. MCA
这是我的Java代码：
public class RegisterActivity extends AppCompatActivity implements View.OnClickListener
{
private EditText TextFname;
private EditText TextMname;
private EditText TextLname;
//private EditText TextDept;
private Spinner SpinDept;
private Spinner SpinProg;
//private EditText TextProg;
private EditText TextSemester;
private EditText TextRolln;
private EditText TextEmail;
private EditText TextPassword;
private EditText TextPasswordConfirm;
//private FirebaseFirestore db = FirebaseFirestore.getInstance();
// Access a Cloud Firestore instance from your Activity
FirebaseFirestore db = FirebaseFirestore.getInstance();
private ProgressBar pBar;
private View bgBlur;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_register);
TextFname = findViewById(R.id.Fname);
TextMname = findViewById(R.id.Mname);
TextLname = findViewById(R.id.Lname);
//TextDept = findViewById(R.id.Dept);
SpinDept = findViewById(R.id.Dept);
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.department_array, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
SpinProg = findViewById(R.id.Prog);
ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource(this,
R.array.programme_array, android.R.layout.simple_spinner_item);
adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
//TextProg = findViewById(R.id.Prog);
TextSemester = findViewById(R.id.Semester);
TextRolln = findViewById(R.id.Rolln);
TextEmail = findViewById(R.id.Email);
TextPassword = findViewById(R.id.Password);
TextPasswordConfirm = findViewById(R.id.PasswordConfirm);
findViewById(R.id.SubmitButton).setOnClickListener(this);
pBar=findViewById(R.id.indeterminateBar);
bgBlur=findViewById(R.id.bgblur);
}
//Validation method
private boolean validate()
{
AwesomeValidation mAwesomeValidation = new AwesomeValidation(BASIC);
mAwesomeValidation.addValidation(TextFname, "\\D+", "Invalid First Name");
mAwesomeValidation.addValidation(TextLname, "\\D+", "Invalid Last Name");
//mAwesomeValidation.addValidation(TextDept, "\\D+", "Invalid Department Name");
//mAwesomeValidation.addValidation(TextProg, "\\D+", "Invalid Programme Name");
mAwesomeValidation.addValidation(TextSemester, "[1-9]+[0-9]{0,}", "Invalid Semester (Cannot be less than 0)");
mAwesomeValidation.addValidation(TextRolln, "[a-zA-Z-0-9\\s]+", "Invalid Roll Number");
mAwesomeValidation.addValidation(TextEmail, Patterns.EMAIL_ADDRESS, "Invalid Email Address");
String regexPassword = "(?=.*[a-z])(?=.*[A-Z])(?=.*[\\d])(?=.*[~`!@#\\$%\\^&\\*\\(\\)\\-_\\+=\\{\\}\\[\\]\\|\\;:\"<>,./\\?]).{6,}";
mAwesomeValidation.addValidation(TextPassword, regexPassword, "Use 6 or more characters with a mix of upper & lower letters, numbers & symbols");
mAwesomeValidation.addValidation(TextPasswordConfirm, TextPassword, "Password does not match");
return mAwesomeValidation.validate();
}
@Override
public void onClick(View v)
{
// Check for particular button click, because this method will be called for every
// click on any view on which onClickListener is set as setOnClickListener(this).
// In this case currently it doesn't matter as there is only one button, but in case
// if you also add for example clear field button, then you need to know which
// button was clicked.
switch (v.getId())
{
case R.id.SubmitButton:
if (validate())
{
String TextDept = SpinDept.getSelectedItem().toString();
String TextProg = SpinProg.getSelectedItem().toString();
pBar.setVisibility(View.VISIBLE);
bgBlur.setVisibility(View.VISIBLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE, WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
//Toast.makeText(this, "Validation successful", Toast.LENGTH_SHORT).show();
/*String Firstname = getTrimmedInput(TextFname);
String Middlename = getTrimmedInput(TextMname);
String Lastname = getTrimmedInput(TextLname);
String Department = getTrimmedInput(TextDept);
String Programme = getTrimmedInput(TextProg);
String Semester = getTrimmedInput(TextSemester);
String Rollnumber = getTrimmedInput(TextRolln);
String Password = getTrimmedInput(TextPassword);*/
String Email = getTrimmedInput(TextEmail);
final CollectionReference dbUsers = db.collection("Students");
final DocumentReference dbDocs = dbUsers.document(Email);
//Student student = new Student(Firstname, Middlename, Lastname, Department, Programme, Integer.parseInt(Semester), Rollnumber, Email, Password);
//Alternative way how to create data model. I think builder pattern is easier
// to operate as you don't have to know in which order you should pass variables
// (especially when you have a lot of them) to model constructor.
// Although I don't know if my class would work as I don't know how your
// DB backend requests data from your student class as in my model some
// getter method name cases are different. Currently I created my Student
// model as example and it's not used.
final StudentImproved studentImproved = new StudentImproved.Builder()
.setFirstName(getTrimmedInput(TextFname))
.setMiddleName(getTrimmedInput(TextMname))
.setLastName(getTrimmedInput(TextLname))
.setDepartment(TextDept)
.setProgramme(TextProg)
.setSemester(Integer.parseInt(getTrimmedInput(TextSemester)))
.setRollNumber(getTrimmedInput(TextRolln))
.setEmail(getTrimmedInput(TextEmail))
.setPassword(getTrimmedInput(TextPassword))
//.setPasswordConfirm(getTrimmedInput(TextPasswordConfirm))
.build();
dbUsers.document(Email)
.get()
.addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>()
{
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task)
{
if (task.isSuccessful())
{
if (task.getResult().exists())
{
pBar.setVisibility(View.GONE);
bgBlur.setVisibility(View.GONE);
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
Toast.makeText(RegisterActivity.this, "You already have your data stored in the database", Toast.LENGTH_LONG).show();
}
else
{
dbDocs.set(studentImproved)
.addOnSuccessListener(new OnSuccessListener<Void>()
{
@Override
public void onSuccess(Void aVoid)
{
pBar.setVisibility(View.GONE);
bgBlur.setVisibility(View.GONE);
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
Toast.makeText(RegisterActivity.this, "Successfully Registered",Toast.LENGTH_LONG).show();
}
})
.addOnFailureListener(new OnFailureListener()
{
@Override
public void onFailure(@NonNull Exception e)
{
pBar.setVisibility(View.GONE);
bgBlur.setVisibility(View.GONE);
getWindow().clearFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE);
Toast.makeText(RegisterActivity.this, e.getMessage(), Toast.LENGTH_LONG).show();
}
});
}
}
}
});
}
/*else
{
Toast.makeText(this, "Validation failed", Toast.LENGTH_LONG).show();
}
break;*/
}
}
private String getTrimmedInput(EditText text)
{
return text.getText().toString().trim();
}
}
这是我的Spinner XML代码：
<Spinner
android:id="@+id/Dept"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="131dp"
android:layout_marginTop="24dp"
android:layout_marginEnd="132dp"
android:entries="@array/department_array"
android:spinnerMode="dropdown"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/Rolln" />
<Spinner
android:id="@+id/Prog"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="179dp"
android:layout_marginTop="24dp"
android:layout_marginEnd="180dp"
android:entries="@array/programme_array"
android:spinnerMode="dropdown"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/Dept" />
这是我的String XML代码：
<string-array name="department_array">
<item>Civil</item>
<item>CSE/IT</item>
<item>Electronics</item>
</string-array>
<string-array name="programme_array">
<item>B.Tech Civil</item>
<item>BCA</item>
<item>MCA</item>
</string-array>
答案 0 :(得分：0)
spinner1.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
// load spinner2 data from database method loadData
List<String> spinner2Data= helper.loadData(spinner1.getSelectedItem().toString());
// Create adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(CurrentActivity.this,android.R.layout.simple_spinner_dropdown_item,android.R.id.text1,spinner2Data);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
spinner2.setAdapter(dataAdapter);
}
@Override
public void onNothingSelected(AdapterView<?> parentView) {
// your code here
}
});
答案 1 :(得分：0)
在第一个微调器的setOnItemSelectedListener中，根据ID匹配或部门名称加载第二个微调器。当您询问将setOnItemSelectedListener放在哪里时，它应该是您活动的第一种方法onCreate中。为此，您可以使用模型类。
SpinProg = findViewById(R.id.Prog);
SpinDept.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> arg0, View arg1,int position, long arg3) {
programmeArray.clear();
// Here put your logic for selecting programs against each department and initialize programmeArray then load progSpinner with that array
/*
* for(int i=0; i<totalPrograms.size; i++){
*
*
*if(totalPrograms.get(i).getName.equals(totalDepartments.get(position).getName)){
* programmeArray.add(totalPrograms.get(i));
* }
* }
* */
ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource(this,
programmeArray, android.R.layout.simple_spinner_item);
adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
}
@Override
public void onNothingSelected(AdapterView<?> arg0) { }
});