【发布时间】：2020-04-29 18:02:30
【问题描述】：
我正在制作一个 android 应用程序，客户和服务提供商通过该应用程序进行协作。首先，服务提供商向客户发送访问请求，指定潜在访问时间。在客户接受访问请求后，一个计时器启动，计算服务提供商访问的剩余时间。 如果时间到期，则应将“访问请求”从“已接受/待定访问列表”中删除并添加到“已完成访问列表”，并且应自动为双方（即服务提供商和客户）评分“5”。我创建了两个函数，一个函数将访问请求从“待定访问列表”转移到“已完成访问列表”，第二个函数调用第一个函数中的第一个函数，为两个用户提供“5”评级。 问题是，当第二个函数运行时，第一个函数无法完成其功能，因为第二个函数在 fires 函数完成之前运行。我正在粘贴两个函数及其调用顺序的代码spinet，并在帖子末尾粘贴了一个更简单的代码版本，以便于理解。
// this functions Transfers Pending/Accepted Visit Request to Completed Visit Request.
public void transferPendingVisitToCompletedVisitListOfCustomerAndServiceProvider(final VisitRequest
visitRequest, final String customerUserName, final int position, final String
serviceProviderUserName){
final DatabaseReference cus_ref =
FirebaseDatabase.getInstance().getReference("Users").child("Customers");
final Customer customer[] = new Customer[1];
cus_ref.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
for(DataSnapshot ssn:dataSnapshot.getChildren()){
customer[0] = ssn.getValue(Customer.class);
if(customer[0].getUserName().equals(customerUserName)){
alCompletedVisitRequests = customer[0].getCompletedVisitsList();
if(alCompletedVisitRequests==null){
alCompletedVisitRequests = new ArrayList<>();
alCompletedVisitRequests.add(visitRequest);
customer[0].setCompletedVisitsList(alCompletedVisitRequests);
alPendingVisitRequests.remove(position);
customer[0].setPendingVisitsList(alPendingVisitRequests);
// updating the UI
PendingVisitRequestsAdapter pendingVisitRequestsAdapter = new
PendingVisitRequestsAdapter();
listViewPendingVisits.setAdapter(pendingVisitRequestsAdapter);
cus_ref.child(customer[0].getId()).setValue(customer[0]);
// Now Checking if the Visit Request is is expired then rating of 5 should be
// given to both users.
if(isPendingVisitExpired==true){
// now handling the responseTime Rating of Service Provider and Customer
automaticallyAddResponseRatingOfServiceProviderandCustomer
(MainActivity.mcustomer.getUserName(),serviceProviderUserName);
}
}
else{ //i-e alCompletedVisitRequests!=null
alCompletedVisitRequests.add(visitRequest);
customer[0].setCompletedVisitsList(alCompletedVisitRequests);
alPendingVisitRequests.remove(position);
customer[0].setPendingVisitsList(alPendingVisitRequests);
// updating the UI
PendingVisitRequestsAdapter pendingVisitRequestsAdapter = new
PendingVisitRequestsAdapter();
listViewPendingVisits.setAdapter(pendingVisitRequestsAdapter);
cus_ref.child(customer[0].getId()).setValue(customer[0]);
// adding Response Time Rating automatically.Definition of this function is below
automaticallyAddResponseRatingOfServiceProviderandCustomer
(MainActivity.mcustomer.getUserName(),serviceProviderUserName);
}
visitRequest.setUserName(MainActivity.mcustomer.getUserName());
addPendingVisitToCompletedVisitInServiceProvider(visitRequest,serviceProviderUserName);
}
}
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
}
现在我粘贴响应时间评级函数的定义，它在上面看到的第一个函数内部调用。
private void automaticallyAddResponseRatingOfServiceProviderandCustomer(final String CustomerUserName, final String ServiceProviderUserName){
DatabaseReference databaseReference =
FirebaseDatabase.getInstance().getReference("Users").child("ServiceProviders");
final String[] ServiceProviderId = new String[1];
final String[] ServiceProviderImageUrl = new String[1];
final ServiceProvider[] serviceProvider = new ServiceProvider[1];
databaseReference.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
for(DataSnapshot ssn:dataSnapshot.getChildren()){
serviceProvider[0] = ssn.getValue(ServiceProvider.class);
if(serviceProvider[0].getUserName().equals(ServiceProviderUserName)){
ServiceProviderId[0] = serviceProvider[0].getId();
ServiceProviderImageUrl[0] = serviceProvider[0].getProfilePicUrl();
ResponseTimeRating responseTimeRating = new
ResponseTimeRating(MainActivity.mcustomer.getImageUrl(),
MainActivity.mcustomer.getUserName(),5);
ArrayList<ResponseTimeRating> responseTimeRatingArrayListOfServiceProvider =
serviceProvider[0].getResponseTimeRatingList();
if(responseTimeRatingArrayListOfServiceProvider==null){
responseTimeRatingArrayListOfServiceProvider = new ArrayList<>();
responseTimeRatingArrayListOfServiceProvider.add(responseTimeRating);
serviceProvider[0].setResponseTimeRatingList(responseTimeRatingArrayListOfServiceProvider);
int averageResponseTimeRatingOfServiceProvider = 0;
int sum = 0;
for (int i = 0; i < responseTimeRatingArrayListOfServiceProvider.size(); i++)
{
sum = sum +
responseTimeRatingArrayListOfServiceProvider.get(i).getResponseRating();
}
averageResponseTimeRatingOfServiceProvider = sum /
responseTimeRatingArrayListOfServiceProvider.size();
serviceProvider[0].setResponseRating(averageResponseTimeRatingOfServiceProvider);
automaticallyAddResponseRatingOfCustomer(ServiceProviderImageUrl[0],ServiceProviderUserName);
break;
}
else{
responseTimeRatingArrayListOfServiceProvider.add(responseTimeRating);
serviceProvider[0].setResponseTimeRatingList(responseTimeRatingArrayListOfServiceProvider);
int averageResponseTimeRatingOfServiceProvider = 0;
int sum = 0;
for (int i = 0; i < responseTimeRatingArrayListOfServiceProvider.size(); i++) {
sum = sum +
responseTimeRatingArrayListOfServiceProvider.get(i).getResponseRating();
}
averageResponseTimeRatingOfServiceProvider = sum /
responseTimeRatingArrayListOfServiceProvider.size();
serviceProvider[0].setResponseRating(averageResponseTimeRatingOfServiceProvider);
automaticallyAddResponseRatingOfCustomer(ServiceProviderImageUrl[0],ServiceProviderUserName);
break;
}
}
}
DatabaseReference newDatabaseReference =
FirebaseDatabase.getInstance().getReference("Users").
child("ServiceProviders").child(serviceProvider[0].getId()
);
newDatabaseReference.setValue(serviceProvider[0]);
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
现在我为这两个函数的代码粘贴了更简单的代码版本，以便于理解。
// definition of first function which transfers Pending Visit From 'Pending Visits List' to
// 'Completed Visit List'
transferPendingVisitToCompletedVisitListOfCustomerAndServiceProvider
(visitRequest,MainActivity.mcustomer.getUserName(),position,ServiceProviderUserName){
// logic for transferring 'Visit Request' From 'Pending Visit List' to 'Completed Visit List'
bla bla bla bla
bla bla bla bla
// now calling the function which gives rating to both Users
automaticallyAddResponseRatingOfServiceProviderandCustomer
(MainActivity.mcustomer.getUserName(),serviceProviderUserName);
}// end definition of first function
问题是，当在第一个函数中调用第二个函数时，第一个函数的功能（即，将“访问请求”从“待定访问列表”转移到“已完成访问列表”）没有完成，这意味着它没有完成转移“访问请求”，但给出评级。
但是如果我从第一个函数内部删除第二个函数（即评级函数），那么第一个函数的功能可以完美运行，并将“访问请求”转移到“完成访问” 列表'。我如何才能完美地运行这两个功能？
【问题讨论】：
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标签： java android firebase asynchronous firebase-realtime-database