Question

Android Studio 3.1，摇篮4.1， Java 1.8， Android 6.0，黄油刀8.8.1

我尝试在Android应用程序上使用ButterKnife。但是我有一个问题。

在 build.gradle 中：

classpath 'com.android.tools.build:gradle:3.1.2'

在 app / build.gradle 中：

implementation "com.jakewharton:butterknife:8.8.1"
kapt "com.jakewharton:butterknife-compiler:8.8.1"

这是我的xml布局： offer_details_pdf.xml

<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <include
        android:id="@+id/offerDetailsToolBarMainContainer"
        layout="@layout/offer_details_top_container"
        android:layout_width="0dp"
        android:layout_height="56dp"/>

    <TextView
        android:id="@+id/noItemsTextView"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:text="@string/no_items"
        android:visibility="gone"/>  

</android.support.constraint.ConstraintLayout>

在我的活动中

public class OfferDetailsPdfActivity extends AppCompatActivity implements MyInterface {
    @BindView(R.id.offerDetailsToolBarMainContainer)
    ConstraintLayout offerDetailsToolBarMainContainer;
    @BindView(R.id.noItemsTextView)
    TextView noItemsTextView;    

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Bundle extras = getIntent().getExtras();
    setContentView(R.layout.offer_details_pdf);
    ButterKnife.bind(this);
}        

// implment method of interface MyInterface
@Override
public void showTopAndBottomContainer() {
   offerDetailsToolBarMainContainer.setVisibility(View.VISIBLE);
}

// implment method of interface MyInterface
@Override
public void showNoItems() {
  noItemsTextView.setVisibility(View.VISIBLE);
}

方法showTopAndBottomContainer()成功的工作。但是方法showNoItems()不是。我收到错误消息：

        java.lang.RuntimeException: Unable to start activity ComponentInfo{com.myproject.android.customer.debug/com.myproject.android.customer.ui.OfferDetailsPdfActivity}: java.lang.IllegalStateException: Required view 'noItemsTextView' with ID 2131296554 for field 'noItemsTextView' was not found. If this view is optional add '@Nullable' (fields) or '@Optional' (methods) annotation.
    android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
    android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
            at android.app.ActivityThread.-wrap11(ActivityThread.java)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:148)
            at android.app.ActivityThread.main(ActivityThread.java:5417)
            at java.lang.reflect.Method.invoke(Native Method)
    com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
        Caused by: java.lang.IllegalStateException: Required view 'noItemsTextView' with ID 2131296554 for field 'noItemsTextView' was not found. If this view is optional add '@Nullable' (fields) or '@Optional' (methods) annotation.
com.myproject.android.customer.ui.OfferDetailsPdfActivity_ViewBinding.<init>(OfferDetailsPdfActivity_ViewBinding.java:73)
            at java.lang.reflect.Constructor.newInstance(Native Method)
            at butterknife.ButterKnife.createBinding(ButterKnife.java:199)
            at butterknife.ButterKnife.bind(ButterKnife.java:124)

为什么不起作用？

Answer 1

XML中没有ID为R.id.noItemsTextView的文本视图。

Answer 2

您可能已经忘记了应用ButterKnife插件。转到您的build.gradle文件，并在下面 apply plugin: 'com.android.library'添加以下内容：apply plugin: 'com.jakewharton.butterknife'

Answer 3

我遇到了同样的问题，并与之抗争了整整一天我的ID很好，我的代码也正确，因为我三倍检查了整整一天然后我发现了一些我从未想过的根本原因

ButterKnife.bind(this);
setContentView(layoutID());

更改为

setContentView(layoutID());
ButterKnife.bind(this);

问题消失了

Android-Butterknife：原因：java.lang.IllegalStateException：未找到所需的视图xxx

3 个答案: