首页 > 解决方案 > recyclerView = (RecyclerView) findViewById(R.id.recyclerView);

问题描述

日志猫2020-11-05 22:49:22.581 1663-1663/? W/ContextImpl:在没有合格用户的情况下调用系统进程中的方法:android.app.ContextImpl.sendBroadcast:1025 com.android.server.location.OppoSuplController.sendSuplConfigUpdateBroadcast:293 com.android.server.location.OppoSuplController.updateSuplConfig: 274 com.android.server.location.OppoSuplController.access$1300:47 com.android.server.location.OppoSuplController$2.handleMessage:619 2020-11-05 22:49:22.582 1663-1663/?D/OppoSuplController:mSuplHostName:supl.google.com,mSuplHostPort:7275,mSuplMode:3,mMsaEnabled:真,mMsbEnabled:真,mSpecHostEnabled:真,mHostSwitchEnabled:真,mTelephonyImsi:40494 2020-11-05 22:49:22.620 2935 -2935/? D/CdmaVolteServiceChecker:onReceive,action = android.intent.action.SERVICE_STATE 2020-11-05 22:49:22。620 2935-2935/? D/CdmaVolteServiceChecker:updateState,检查 = 假 2020-11-05 22:49:22.620 2935-2935/?D/CdmaVolteServiceChecker:shouldShowVolteAlert cdma混合电压支持,返回false。2020-11-05 22:49:22.844 1663-3532/? E/进程:get_ion_cache_memory:无法打开/d/ion/heaps/system 2020-11-05 22:49:22.980 1663-4211/?E/进程:get_ion_cache_memory:无法打开/d/ion/heaps/system 2020-11-05 22:49:25.681 22324-22457/?E/Parcel:此处不支持读取 NULL 字符串。2020-11-05 22:49:27.649 1173-1382/? E/存储:getDiskStats 失败,结果为 NOT_SUPPORTED,大小为 0 2020-11-05 22:49:28.068 1663-1663/?D/BatteryService:发送广播:oppo.intent.action.BATTERY_DATA_UPDATE 2020-11-05 22:49:28.069 1663-1663/? W/ContextImpl:在没有合格用户的情况下调用系统进程中的方法:android.app.ContextImpl。sendBroadcast:1025 com.android.server.BatteryService$8.run:803 android.os.Handler.handleCallback:873 android.os.Handler.dispatchMessage:99 android.os.Looper.loop:226 2020-11-05 22:49 :29.396 10556-10598/? W/Settings:设置 plane_mode_on 已从 android.provider.Settings.System 移至 android.provider.Settings.Global,返回只读值。2020-11-05 22:49:29.520 1663-1663/? D/意图:disableDeathOnFileUriExposure com.android.chrome 2020-11-05 22:49:29.568 19152-19332/? I/BtGatt.ScanManager:msg.what = 6 2020-11-05 22:49:29.591 818-818/?i//vendor/bin/hw/vendor.qti.hardware.servicetracker@1.0-service: service: com.android.chrome/org.chromium.components.background_task_scheduler.BackgroundTaskJobService的服务连接大小删除后为0 2020-11- 05 22:49:29.591 818-818/?我//供应商/bin/hw/vendor.qti.hardware。servicetracker@1.0-service:客户端的客户端连接大小:系统删除后为 16 2020-11-05 22:49:29.593 22324-23131/? D/意图:disableDeathOnFileUriExposure com.android.chrome 2020-11-05 22:49:29.611 22324-22324/? E/cr_BkgrdTaskJS: 尝试完成非当前 BackgroundTask。2020-11-05 22:49:29.683 14000-24041/? E/MCS2.0_CIPHER_ALGO: checkSign 1 2020-11-05 22:49:29.691 14000-24041/? D/MCS2.0_CIPHER_ALGO:riv native_AES_encrypt 标志 0 2020-11-05 22:49:34.182 1663-2761/?带看门狗:!@WatchDog_3773 2020-11-05 22:49:29.705 14000-24041/? D/MCS2.0_CIPHER_ALGO:riv native_AES_encrypt 标志 0 2020-11-05 22:49:34.577 1663-1663/?D/意图:disableDeathOnFileUriExposure com.facebook.katana 2020-11-05 22:49:34.622 19152-19332/? I/BtGatt.ScanManager: msg.what = 6 2020-11-05 22:49:35.253 818-818/? 我//供应商/bin/hw/vendor.qti.hardware。servicetracker@1.0-service:服务连接的大小:com.facebook.katana/com.facebook.analytics2.logger.LollipopUploadService 删除后为 0 2020-11-05 22:49:35.253 818-818/? I//vendor/bin/hw/vendor.qti.hardware.servicetracker@1.0-service: 客户端的客户端连接大小: 删除后系统为16 2020-11-05 22:49:38.656 1663-1673/? I/system_server:后台并发复制GC释放90991(7MB)个AllocSpace对象,40(976KB)LOS对象,17%空闲,36MB/44MB,暂停563us共168.097ms 2020-11-05 22:49:38.830 1663-1663/ ? D/BatteryService:发送广播:oppo.intent.action.BATTERY_DATA_UPDATE 2020-11-05 22:49:38.831 1663-1663/? W/ContextImpl:在没有合格用户的情况下调用系统进程中的方法:android.app.ContextImpl.sendBroadcast:1025 com.android.server.BatteryService$8.run:803 android.os.Handler。handleCallback:873 android.os.Handler.dispatchMessage:99 android.os.Looper.loop:226 2020-11-05 22:49:39.072 1663-4881/? W/System.err:java.io.FileNotFoundException:/proc/blackCheckStatus(没有这样的文件或目录)2020-11-05 22:49:39.073 1663-4881/?W/System.err:在 java.io.FileInputStream.open0(本机方法)2020-11-05 22:49:39.073 1663-4881/?W/System.err:在 java.io.FileInputStream.open(FileInputStream.java:231) 2020-11-05 22:49:39.073 1663-4881/?W/System.err:在 java.io.FileInputStream.(FileInputStream.java:165) 2020-11-05 22:49:39.073 1663-4881/?W/System.err:在 android.os.FileUtils.readTextFile(FileUtils.java:514) 2020-11-05 22:49:39.073 1663-4881/?W/System.err:在 com.android.server.BootReceiver$2.run(BootReceiver.java:232) 2020-11-05 22:49:39.074 1663-4882/?W/System.err: java.io.FileNotFoundException: /proc/brightCheckStatus (没有这样的文件或目录) 2020-11-05 22:49:39.075 1663-4882/? W/System.err:在 java.io.FileInputStream.open0(本机方法)2020-11-05 22:49:39.075 1663-4882/?W/System.err:在 java.io.FileInputStream.open(FileInputStream.java:231) 2020-11-05 22:49:39.075 1663-4882/?W/System.err:在 java.io.FileInputStream.(FileInputStream.java:165) 2020-11-05 22:49:39.075 1663-4882/?W/System.err:在 android.os.FileUtils.readTextFile(FileUtils.java:514) 2020-11-05 22:49:39.075 1663-4882/?W/System.err:在 com.android.server.BootReceiver$3.run(BootReceiver.java:259) 2020-11-05 22:49:40.739 818-818/?I//vendor/bin/hw/vendor.qti.hardware.servicetracker@1.0-service: 客户端连接大小: com.android.chrome 删除后为3 2020-11-05 22:49:41.368 5961-5965/ ? E/rutils:releaseProcess gCount = 1 2020-11-05 22:49:41.475 10556-10598/? W/Settings:设置 plane_mode_on 已从 android.provider.Settings.System 移至 android.provider.Settings.Global,返回只读值。2020-11-05 22:49:49.067 1663-1663/? D/BatteryService:发送广播:oppo.intent.action.BATTERY_DATA_UPDATE 2020-11-05 22:49:49.068 1663-1663/? W/ContextImpl:在没有合格用户的情况下调用系统进程中的方法:android.app.ContextImpl.sendBroadcast:1025 com.android.server.BatteryService$8.run:803 android.os.Handler.handleCallback:873 android.os。 Handler.dispatchMessage:99 android.os.Looper.loop:226 2020-11-05 22:49:53.552 10556-10598/? W/Settings:设置 plane_mode_on 已从 android.provider.Settings.System 移至 android.provider.Settings.Global,返回只读值。2020-11-05 22:49:55。710 22324-22457/? E/Parcel:此处不支持读取 NULL 字符串。2020-11-05 22:50:00.080 1663-1663/? D/电池服务:发送广播:oppo.intent.action.BATTERY_DATA_UPDATE 2020-11-05 22:50:00.081 1663-1663/? W/ContextImpl:在没有合格用户的情况下调用系统进程中的方法:android.app.ContextImpl.sendBroadcast:1025 com.android.server.BatteryService$8.run:803 android.os.Handler.handleCallback:873 android.os。 Handler.dispatchMessage:99 android.os.Looper.loop:226 构建错误

执行任务:项目 G:\SOFTWARES\Recyclerview 中的 [:app:assembleDebug]

任务 :app:preBuild UP-TO-DATE 任务 :app:preDebugBuild UP-TO-DATE 任务 :app:compileDebugAidl NO-SOURCE 任务 :app:generateDebugBuildConfig UP-TO-DATE 任务 :app:compileDebugRenderscript NO-SOURCE 任务 :app: javaPreCompileDebug 最新任务 :app:generateDebugResValues 最新任务 :app:generateDebugResources 最新任务 :app:createDebugCompatibleScreenManifests 最新任务 :app:extractDeepLinksDebug 最新任务 :app: processDebugManifest 最新任务 :app:mergeDebugShaders 最新任务 :app:compileDebugShaders NO-SOURCE 任务 :app:generateDebugAssets 最新任务 :app:mergeDebugAssets 最新任务 :app:mergeDebugResources 任务:app:processDebugResources

任务 :app:compileDebugJavaWithJavac G:\SOFTWARES\Recyclerview\app\src\main\java\com\example\recyclerview\MainActivity.java:23: 错误:找不到符号 recyclerView = (RecyclerView) findViewById(R.id.recyclerView) ; ^ 符号:变量 recyclerView 位置:类 id 注意:G:\SOFTWARES\Recyclerview\app\src\main\java\com\example\recyclerview\ProductAdapter.java 使用或覆盖已弃用的 API。注意:使用 -Xlint:deprecation 重新编译以获取详细信息。1 个错误

任务 :app:compileDebugJavaWithJavac 失败

FAILURE:构建失败并出现异常。

编译失败;有关详细信息,请参阅编译器错误输出。

在 1m 14s 内构建失败 11 个可操作的任务:3 个已执行,8 个是最新的

Mainactivity.java包 com.example.recyclerview;

import androidx.appcompat.app.AppCompatActivity; 
import androidx.recyclerview.widget.LinearLayoutManager; 
import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;

import java.util.ArrayList; import java.util.List;

public class MainActivity extends AppCompatActivity {
    //List<Product> ProductList;
     RecyclerView recyclerView;
     List<Object> productList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        //getting the recyclerview from xml
        recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));

        //initializing the productlist
        productList = new ArrayList<>();


        //adding some items to our list
        productList.add(
                new Product(
                        1,
                        "Apple MacBook Air Core i5 5th Gen - (8 GB/128 GB SSD/Mac OS Sierra)",
                        "13.3 inch, Silver, 1.35 kg",
                        4.3,
                        60000,
                        R.drawable.macbook));

        productList.add(
                new Product(
                        1,
                        "Dell Inspiron 7000 Core i5 7th Gen - (8 GB/1 TB HDD/Windows 10 Home)",
                        "14 inch, Gray, 1.659 kg",
                        4.3,
                        60000,
                        R.drawable.dellinspiron));

        productList.add(
                new Product(
                        1,
                        "Microsoft Surface Pro 4 Core m3 6th Gen - (4 GB/128 GB SSD/Windows 10)",
                        "13.3 inch, Silver, 1.35 kg",
                        4.3,
                        60000,
                        R.drawable.surface));

        //creating recyclerview adapter
        ProductAdapter adapter = new ProductAdapter(this, productList);

        //setting adapter to recyclerview
        recyclerView.setAdapter(adapter);
    } }

布局.product.xml

<androidx.appcompat.widget.LinearLayoutCompat 
xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <androidx.cardview.widget.CardView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp">

        <androidx.appcompat.widget.LinearLayoutCompat

            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="8dp">

            <ImageView
                android:id="@+id/imageView"
                android:layout_width="120dp"
                android:layout_height="90dp"
                android:padding="4dp" />

            <TextView
                android:id="@+id/textViewTitle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="5dp"
                android:layout_toRightOf="@id/imageView"
                android:text="Apple MacBook Air Core i5 5th Gen - (8 GB/128 GB SSD/Mac OS Sierra)"
                android:textAppearance="@style/Base.TextAppearance.AppCompat.Small"
                android:textColor="#000000" />

            <TextView
                android:id="@+id/textViewShortDesc"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/textViewTitle"
                android:layout_marginLeft="5dp"
                android:layout_marginTop="5dp"
                android:layout_toRightOf="@id/imageView"
                android:text="13.3 Inch, 256 GB"
                android:textAppearance="@style/Base.TextAppearance.AppCompat.Small" />

            <TextView
                android:id="@+id/textViewRating"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/textViewShortDesc"
                android:layout_marginLeft="5dp"
                android:layout_marginTop="5dp"
                android:layout_toRightOf="@id/imageView"
                android:background="@color/colorPrimary"
                android:paddingLeft="15dp"
                android:paddingRight="15dp"
                android:text="4.7"
                android:textAppearance="@style/Base.TextAppearance.AppCompat.Small.Inverse"
                android:textStyle="bold" />

            <TextView
                android:id="@+id/textViewPrice"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/textViewRating"
                android:layout_marginLeft="5dp"
                android:layout_marginTop="5dp"
                android:layout_toRightOf="@id/imageView"
                android:text="INR 56990"
                android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
                android:textStyle="bold" />

        </androidx.appcompat.widget.LinearLayoutCompat>

    </androidx.cardview.widget.CardView>

</androidx.appcompat.widget.LinearLayoutCompat>

activity_main.xml

<androidx.constraintlayout.widget.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"
tools:context=".MainActivity">

<androidx.recyclerview.widget.RecyclerView
    android:layout_width="354dp"
    android:layout_height="626dp"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayou

我正在使用以下网站https://www.simplifiedcoding.net/android-recyclerview-cardview-tutorial/进行回收商参考

标签: androidandroid-studioandroid-layoutandroid-recyclerview

解决方案


请在recyclerview中设置id。

android:id="@+id/recyclerView"

 <androidx.constraintlayout.widget.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"
     tools:context=".MainActivity">

     <androidx.recyclerview.widget.RecyclerView
          android:id="@+id/recyclerView"
          android:layout_width="354dp"
          android:layout_height="626dp"
          app:layout_constraintBottom_toBottomOf="parent"
          app:layout_constraintEnd_toEndOf="parent"
          app:layout_constraintStart_toStartOf="parent"
          app:layout_constraintTop_toTopOf="parent" />

  </androidx.constraintlayout.widget.ConstraintLayout>

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