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[英]Android in TabLayout, ViewPager Fragments not updating consistantly
[英]Android - TabLayout & ViewPager > Fragments > OnListFragmentInteractionListener
我是Android新手,因此開始構建“導航抽屜活動”項目。 我在Activity_main.xml中添加了TabLayout和ViewPager,現在可以在不同列表之間滑動。 當我單擊列表中的項目時,它會在MainActivity.java中調用onListFragmentInteraction。 我嘗試使用下面的代碼在用戶單擊列表中的項目時動態添加一個Detail片段,但出現此錯誤。 我的MainActivity類執行“ CustomerFragment.OnListFragmentInteractionListener”
首先 ,我在ViewPager中顯示詳細片段的嘗試是否正確? 我在下面嘗試的代碼是否會在當前選項卡中添加一個片段?
其次 ,有人知道我為什么會收到此錯誤嗎?
非常感謝!
錯誤:
java.lang.RuntimeException:com.myproject.android.MainActivity@186e12d必須實現OnFragmentInteractionListener
主要活動:
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener, TabLayout.OnTabSelectedListener, CustomerFragment.OnListFragmentInteractionListener, GoogleApiClient.OnConnectionFailedListener {
private GoogleApiClient mGoogleApiClient;
private TabLayout tabLayout;
private ViewPager viewPager;
private Pager adapter;
public void onListFragmentInteraction(Customer customer){
FragmentManager fm = getSupportFragmentManager();
CustomerDetailFragment fragment = CustomerDetailFragment.newInstance(customer);
fm.beginTransaction().add(R.id.pager, fragment).commit();
}
@Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(TabLayout.Tab tab) { }
@Override
public void onTabReselected(TabLayout.Tab tab) { }
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
tabLayout = (TabLayout) findViewById(R.id.tabLayout);
tabLayout.addTab(tabLayout.newTab().setText("Home"));
tabLayout.addTab(tabLayout.newTab().setText("Customers"));
tabLayout.addTab(tabLayout.newTab().setText("Jobs"));
tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
viewPager = (ViewPager) findViewById(R.id.pager);
adapter = new Pager(getSupportFragmentManager(), tabLayout.getTabCount());
viewPager.setAdapter(adapter);
tabLayout.addOnTabSelectedListener(this);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.addDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
FirebaseMessaging.getInstance().subscribeToTopic("global");
String token = FirebaseInstanceId.getInstance().getToken();
// Check Google Play Services
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this, this)
.addApi(Drive.API)
.addScope(Drive.SCOPE_FILE)
.build();
// test
Date d = new Date();
DbHandler dbHandler = new DbHandler(this, null, null, 1);
Customer customer = new Customer(1, 1, 1, 1, "Test", "Test", "Test", false, d, 1, d, 1);
dbHandler.addCustomer(customer);
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_camera) {
startActivity(new Intent(this, LoginActivity.class));
} else if (id == R.id.nav_gallery) {
startActivity(new Intent(this, SyncActivity.class));
} else if (id == R.id.nav_slideshow) {
} else if (id == R.id.nav_manage) {
} else if (id == R.id.nav_share) {
} else if (id == R.id.nav_send) {
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
}
客戶清單片段:
public class CustomerFragment extends Fragment {
private OnListFragmentInteractionListener mListener;
public CustomerFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_customer_list, container, false);
SearchView sv = (SearchView) view.findViewById(R.id.searchview);
RecyclerView rv = (RecyclerView) view.findViewById(R.id.recyclerview);
// Adapter
rv.setLayoutManager(new LinearLayoutManager(view.getContext()));
final CustomerAdapter adapter = new CustomerAdapter(getCustomers(), mListener);
rv.setAdapter(adapter);
// Search
sv.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String query) {
return false;
}
@Override
public boolean onQueryTextChange(String query) {
//adapter.getFilter().filter(query);
return false;
}
});
return view;
}
private ArrayList<Customer> getCustomers() {
DbHandler dbHandler = new DbHandler(this.getActivity(), null, null, 1);
ArrayList<Customer> customers = dbHandler.getCustomers();
return customers;
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnListFragmentInteractionListener) {
mListener = (OnListFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString() + " must implement OnListFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
public interface OnListFragmentInteractionListener {
void onListFragmentInteraction(Customer customer);
}
}
客戶適配器:
public class CustomerAdapter extends RecyclerView.Adapter<CustomerAdapter.ViewHolder> {
private final List<Customer> mValues;
private final OnListFragmentInteractionListener mListener;
public CustomerAdapter(List<Customer> items, OnListFragmentInteractionListener listener) {
mValues = items;
mListener = listener;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.fragment_customer, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
Customer customer = mValues.get(position);
holder.mItem = customer;
holder.mIdView.setText(String.valueOf(customer.getId()));
holder.mContentView.setText(customer.getCompanyName());
holder.mView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (null != mListener) {
mListener.onListFragmentInteraction(holder.mItem);
}
}
});
}
@Override
public int getItemCount() {
return mValues.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
public final View mView;
public final TextView mIdView;
public final TextView mContentView;
public Customer mItem;
public ViewHolder(View view) {
super(view);
mView = view;
mIdView = (TextView) view.findViewById(R.id.id);
mContentView = (TextView) view.findViewById(R.id.content);
}
@Override
public String toString() {
return super.toString() + " '" + mContentView.getText() + "'";
}
}
}
更新:看來我需要同時添加onListFragmentInteraction和onFragmentInteraction。 第一個用於CustomerListFragment,第二個用於CustomerDetailFragment。
為了使CustomerDetailFragment與這些選項卡一起使用,我按照以下步驟進行了操作: https : //medium.com/@nilan/separate-back-navigation-for-a-tabbed-view-pager-in-android-459859f607e4 #.lrjeexdcp
@Override
public void onListFragmentInteraction(Customer customer){
FragmentManager fm = getSupportFragmentManager();
CustomerDetailFragment fragment = CustomerDetailFragment.newInstance(customer);
fm.beginTransaction().add(R.id.pager, fragment).commit();
}
@Override
public void onFragmentInteraction(Uri uri) {
}
你需要放
public void onListFragmentInteraction(Customer customer){
FragmentManager fm = getSupportFragmentManager();
CustomerDetailFragment fragment = CustomerDetailFragment.newInstance(customer);
fm.beginTransaction().add(R.id.pager, fragment).commit();
}
在您的MainActivity
類內部,而不是外部。
如果這實際上不是您的代碼的方式,請編輯您的答案以分解這些塊,以准確地表示您的代碼是如何構建的,並在您的偵聽器片段中包含您的接口。 您可能還需要在@Override
上述標簽onListFragmentInteraction
實施
編輯
正如我上面提到的,你需要把@Override
標簽上面onListFragmentInteraction
落實,看你已經有了每隔監聽器實現。
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