我最近在学习领券联盟的app编写，到61的时候将LoadingView加入到Activity_Ticket中，也Binding了TicketActivity，可是每次运行后点击进入TicketActivity的时候一直在报错没有找到相应的LoadingView。

报错提示：

E/AndroidRuntime: FATAL EXCEPTION: main

  Process: com.reiinoki.taobaounion, PID: 13788

  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.reiinoki.taobaounion/com.reiinoki.taobaounion.ui.activity.TicketActivity}: java.lang.IllegalStateException: Required view 'ticket_cover_loading' with ID 2131296708 for field 'loadingView' was not found. If this view is optional add '@Nullable' (fields) or '@Optional' (methods) annotation.

    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2913)

    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)

    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)

    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)

    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)

    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)

    at android.os.Handler.dispatchMessage(Handler.java:106)

    at android.os.Looper.loop(Looper.java:193)

    at android.app.ActivityThread.main(ActivityThread.java:6669)

    at java.lang.reflect.Method.invoke(Native Method)

    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)

    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

   Caused by: java.lang.IllegalStateException: Required view 'ticket_cover_loading' with ID 2131296708 for field 'loadingView' was not found. If this view is optional add '@Nullable' (fields) or '@Optional' (methods) annotation.

    at butterknife.internal.Utils.findRequiredView(Utils.java:84)

    at butterknife.internal.Utils.findRequiredViewAsType(Utils.java:96)

    at com.reiinoki.taobaounion.ui.activity.TicketActivity_ViewBinding.<init>(TicketActivity_ViewBinding.java:33)

    at java.lang.reflect.Constructor.newInstance0(Native Method)

    at java.lang.reflect.Constructor.newInstance(Constructor.java:343)

    at butterknife.ButterKnife.bind(ButterKnife.java:170)

    at butterknife.ButterKnife.bind(ButterKnife.java:99)

    at com.reiinoki.taobaounion.base.BaseActivity.onCreate(BaseActivity.java:19)

    at android.app.Activity.performCreate(Activity.java:7136)

    at android.app.Activity.performCreate(Activity.java:7127)

    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)

    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2893)

    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048) 

    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 

    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 

    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 

    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808) 

    at android.os.Handler.dispatchMessage(Handler.java:106) 

    at android.os.Looper.loop(Looper.java:193) 

    at android.app.ActivityThread.main(ActivityThread.java:6669) 

    at java.lang.reflect.Method.invoke(Native Method) 

    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 

    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858) 

LoadingView部分在xml上的代码

<com.reiinoki.taobaounion.ui.custom.LoadingView
    android:id="@+id/ticket_cover_loading"
    android:layout_height="@dimen/dp_33"
    android:layout_width="@dimen/dp_33"
    android:layout_centerInParent="true"/>

TicketActivity.java与LoadingView相关的代码

@BindView(R.id.ticket_cover_loading)
public LoadingView loadingView;

@BindView(R.id.ticket_load_retry)
public View retryLoadingText;

@Override
public void onError() {
    if (loadingView != null) {
        loadingView.setVisibility(View.GONE);
    }
    if (retryLoadingText != null) {
        retryLoadingText.setVisibility(View.VISIBLE);
    }
}

@Override
public void onTicketLoaded(String cover, TicketResult result) {

    LogUtils.debug(this, "onTicketLoaded");
    if (mCover != null && !TextUtils.isEmpty(cover)) {
        String coverPath = UrlUtils.getCoverPath(cover);
        Glide.with(this).load(coverPath).into(mCover);
    }

    if (result != null && result.getData().getTbk_tpwd_create_response() != null) {
        mTicketCode.setText(result.getData().getTbk_tpwd_create_response().getData().getModel());
    }

    if (loadingView != null) {
        loadingView.setVisibility(View.GONE);
    }
}

@Override
public void onLoading() {
    if (retryLoadingText != null) {
        retryLoadingText.setVisibility(View.GONE);
    }
    if (loadingView != null) {
        loadingView.setVisibility(View.VISIBLE);
    }
}

顺便说我试过将LoadingView标记为@Nullable倒是可以成功进入TickActivity了就是没办法操作loadingView了...