如何在导航抽屉活动中完成双向数据绑定？

Question

 <layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>
        <variable
            name="policyinfo"
            type="com.exlservice.lifeprov1.service.model.GetPolicyInfoResponse" />

        <variable
            name="surrenderquote"
            type="com.exlservice.lifeprov1.service.model.SurrenderQuoteResponse" />
    </data>
<android.support.constraint.ConstraintLayout
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:id="@+id/c1"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context=".view.ui.PolicyInfo"
    tools:showIn="@layout/app_bar_policy_info">
    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:background="#223d50"
        android:layout_height="match_parent">
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">
            <LinearLayout android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical"
                android:background="@drawable/policy_prime_info_bg"
                android:layout_marginTop="20dp"
                android:layout_marginLeft="10dp"
                android:layout_marginRight="10dp"
                >
                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="8dp"
                    android:orientation="horizontal">

                    <TextView
                        android:layout_width="0dp"
                        android:layout_marginLeft="5dp"
                        android:layout_height="wrap_content"
                        android:text="@{policyInfo.ProductId}"
                        android:textColor="#76c6db"
                        android:layout_weight="1"
                        android:typeface="serif"
                        android:textStyle="bold"
                        android:id="@+id/id_fc_first_key"/>
                    <TextView
                        android:layout_width="0dp"
                        android:textColor="#76c6db"
                        android:textStyle="bold"
                        android:typeface="serif"
                        android:layout_height="wrap_content"
                        android:text="@{policyInfo.Contract}"
                        android:layout_weight="1"
                        android:id="@+id/id_fc_second_key"/>

                </LinearLayout>
           </LinearLayout>
    </android.support.v4.widget.NestedScrollView>
</android.support.constraint.ConstraintLayout>
</layout>

public class PolicyInfo extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {
APIInterface apiInterface;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    binding= DataBindingUtil.setContentView(this,R.layout.activity_policy_info);
    Intent intent = getIntent();
    String sCompanyCode = intent.getStringExtra("CompanyCode");
    String sPolicyNumber = intent.getStringExtra("PolicyNumber");
    String sWayPoint = intent.getStringExtra("WayPoint");
    Log.e("onCreate: ",sCompanyCode+"   "+sPolicyNumber );
    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
    String currentTime = sdf.format(new Date());
    SurrenderQuoteInput surrenderQuoteInput = new SurrenderQuoteInput();
    surrenderQuoteInput.setCoderID("TRN7");
    surrenderQuoteInput.setCompanyCode("01");



    PolicyDetailsReq policyDetailsReq= new PolicyDetailsReq();
    policyDetailsReq.setCoderID("TRN7");

    getPolicyInfoRequest.setPolicyDetailsReq(policyDetailsReq);

    PolicyInfoViewModel.Factory factory = new PolicyInfoViewModel.Factory(
            getApplication(),getPolicyInfoRequest,surrenderQuoteRequest);

    pd = new ProgressDialog(PolicyInfo.this);
    //setContentView(R.layout.activity_policy_info);

    pref= getSharedPreferences("LoginDetail", 0);
    Toolbar toolbar =  findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    getSupportActionBar().setTitle("Poilcy Info");
    apiInterface = APIClient.getClient().create(APIInterface.class);
    FloatingActionButton fab =  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();
        }
    });
    apiInterface = APIClient.getClient().create(APIInterface.class);

    PolicyInfoViewModel viewModel =
            ViewModelProviders.of(this,factory).get(PolicyInfoViewModel.class);
    **observeViewModel**(viewModel);
    pd.setTitle("Loading...");
    pd.setMessage("Please wait.");
    pd.setCancelable(false);
    // show it
    pd.show();
    DrawerLayout drawer =  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 =  findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);

}
private void **observeViewModel**(final PolicyInfoViewModel viewModel) {
    // Update the list when the data changes
    viewModel.getPolicyInfoResponsetObservable().observe(this, new Observer<GetPolicyInfoResponse>() {
        @Override
        public void onChanged(@Nullable GetPolicyInfoResponse getPolicyInfoResponse) {
            if(getPolicyInfoResponse!=null) {
                viewModel.setPolicyInfoResult(getPolicyInfoResponse);
                binding.setPolicyinfo(getPolicyInfoResponse);
            }
           /* if (getLastAccessedDetailsResult != null) {
                getLastAccessedDetailsRes=getLastAccessedDetailsResult;
                viewModel.setLastAccessedDetailsResult(getLastAccessedDetailsResult);
                setupViewPager(viewPager);
            }*/
        }

    });
}

上面显示类转换异常的错误Android.Support.V7.Widget.AppCompattExtView不能转换为Android.Support.Design.Widget.NavigationView

全堆栈跟踪

Answer 1

您似乎试图用AppCompatTextView初始化NavigationView

NavigationView navigationView =  findViewById(R.id.nav_view);

在onCreate（）方法中的PolicyInfo活动第58行中

请尝试检查您在何处使用此ID(r.ID.nav_view)，并正确初始化此ID(r.ID.nav_view)