如何修复错误:致命异常:java.lang.NoClassDefFoundError

Question

我经常在firebase中得到这个错误。屏幕截图中显示了不正确的方法。我不明白他为什么会犯错误。我认为这个方法没有任何错误。该方法的目的是将共享的首选项数据分配给默认值​​晚上。仅此而已。提前谢谢。

屏幕截图：https://i.stack.imgur.com/SMHyH.png

报警接收器类

public class AlarmReceiver extends BroadcastReceiver {
int notificationID;
private SharedPreferences.Editor editor;
private SharedPreferences.OnSharedPreferenceChangeListener sharedpreflistener;
private SharedPreferences sharedPreferences;
private String MAIN_DATA = "com.xxx.xxx.MAIN";
@RequiresApi(api = Build.VERSION_CODES.O)
public void createNotification(Context context, String title, String text, String bigtext, int icon, int i, String channelID, int color,int[] saatler,int[] dklar) {
Intent myintent = new Intent(context, SplashActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, myintent, PendingIntent.FLAG_UPDATE_CURRENT);
NotificationCompat.Builder mbuilder = new NotificationCompat.Builder(context.getApplicationContext(), channelID);
NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
NotificationChannel channel = new NotificationChannel(channelID, channelID, NotificationManager.IMPORTANCE_HIGH);
channel.setDescription(channelID);
Objects.requireNonNull(notificationManager).createNotificationChannel(channel);

mbuilder
.setSmallIcon(icon)
.setChannelId(channelID)
.setContentIntent(pendingIntent)
.setAutoCancel(true)
.setChannelId(channelID)
.setColor(color)
.setDefaults(Notification.DEFAULT_ALL)
.setWhen(System.currentTimeMillis())
.setContentTitle(title)
.setContentText(text)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_SOUND)
.setContentInfo("Info")
.setStyle(new NotificationCompat.BigTextStyle()
.bigText(bigtext));
notificationManager.notify(i, mbuilder.build());

AlarmHelper alarmHelper=new AlarmHelper();
alarmHelper.helper(context,saatler,dklar);
}
public void waterDataClear(Context context) {
sharedPreferences = context.getSharedPreferences(MAIN_DATA, Context.MODE_PRIVATE);
editor = sharedPreferences.edit();
editor.putFloat(SU_KAYIT,  0.0f);
editor.putBoolean(SU_DIALOG, true);
editor.putInt(SU_ML, 0);
editor.apply();
WaterAlarmClear waterClear=new WaterAlarmClear();
waterClear.alarmClear(context);
}
@RequiresApi(api = Build.VERSION_CODES.O)
@Override
public void onReceive(Context context, Intent intent) {
sharedPreferences = context.getSharedPreferences(MAIN_DATA, Context.MODE_PRIVATE);

Bundle extras = intent.getExtras();
notificationID = Objects.requireNonNull(extras).getInt("NotificationID");
if (notificationID == 6) {
createNotification(context, context.getString(R.string.tracker_title), trackertxt, trackertxt, R.mipmap.ic_launcher, 6, context.getString(R.string.weight_channel), context.getResources().getColor(R.color.colorhedef), saatler, dklar);
notificationID = 0;
}

if (notificationID == 10) {
waterDataClear(context);
notificationID = 0;
}

}

舱单

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.xxx.xxx"
android:installLocation="auto">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.SET_ALARM" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:resizeableActivity="false"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme"
tools:ignore="AllowBackup,GoogleAppIndexingWarning,InnerclassSeparator,UnusedAttribute"
tools:targetApi="n">
<activity
android:name=".MainActivity"
android:windowSoftInputMode="stateAlwaysHidden">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>

<receiver android:name=".AlarmReceiver" />
</application>
</manifest>

Fatal Exception: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/app/NotificationChannel;
at androidx.core.app.NotificationCompat$Builder.setSmallIcon(NotificationCompat.java)
at com.xxxx.xxxx.AlarmReceiver.waterDataClear(AlarmReceiver.java)
at android.app.ActivityThread.handleReceiver(ActivityThread.java:2739)
at android.app.ActivityThread.access$1800(ActivityThread.java:157)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1428)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5437)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.6.3'
classpath 'com.google.gms:google-services:4.3.3'
classpath 'com.google.firebase:firebase-crashlytics-gradle:2.0.0'
}
}
allprojects {
repositories {
maven {url 'https://jitpack.io'}
google()
jcenter()
mavenCentral()
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'
apply plugin: 'com.google.firebase.crashlytics'
android {
compileSdkVersion 29
buildToolsVersion "29.0.2"
defaultConfig {
applicationId "com.xxx.xxx"
minSdkVersion 19
targetSdkVersion 29
versionCode 10
versionName '1.0.5.5'
multiDexEnabled true
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled true
shrinkResources true
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'com.google.android.material:material:1.2.0-alpha06'
implementation 'com.android.volley:volley:1.1.1'
implementation 'com.google.firebase:firebase-core:17.4.0'
implementation 'com.google.firebase:firebase-ads:19.1.0'
implementation 'com.google.android.gms:play-services-ads:19.1.0'
implementation 'com.google.firebase:firebase-analytics:17.4.0'
implementation 'com.google.firebase:firebase-crashlytics:17.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
}

public class WaterAlarmClear {
public void alarmClear(Context context){
Calendar suthatDay = Calendar.getInstance();
Calendar sutoday = Calendar.getInstance();
int sutoday_month_day = sutoday.get(Calendar.DAY_OF_MONTH);
int sutoday_month = sutoday.get(Calendar.MONTH);
int sutoday_year = sutoday.get(Calendar.YEAR);
suthatDay.setTime(new Date(0)); /* reset */
suthatDay.set(Calendar.DAY_OF_MONTH, sutoday_month_day);
suthatDay.set(Calendar.MONTH, sutoday_month); // 0-11 so 1 less
suthatDay.set(Calendar.YEAR, sutoday_year);
suthatDay.set(Calendar.HOUR_OF_DAY, 23);
suthatDay.set(Calendar.MINUTE, 50);
suthatDay.set(Calendar.SECOND, 0);
suthatDay.set(Calendar.MILLISECOND, 0);
if (suthatDay.getTimeInMillis() - sutoday.getTimeInMillis() < 0) {
suthatDay.set(Calendar.DAY_OF_MONTH, sutoday_month_day + 1);
} else {
suthatDay.set(Calendar.DAY_OF_MONTH, sutoday_month_day);
}

AlarmManager sualarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
Intent suintent = new Intent(context, AlarmReceiver.class);
suintent.putExtra("NotificationID", 10);
PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 23, suintent, PendingIntent.FLAG_UPDATE_CURRENT);
if (Build.VERSION.SDK_INT >= 23) {
Objects.requireNonNull(sualarmManager).setExactAndAllowWhileIdle(AlarmManager.RTC_WAKEUP, suthatDay.getTimeInMillis(), pendingIntent);
} else if (Build.VERSION.SDK_INT >= 19) {
Objects.requireNonNull(sualarmManager).setExact(AlarmManager.RTC_WAKEUP, suthatDay.getTimeInMillis(), pendingIntent);
} else {
Objects.requireNonNull(sualarmManager).set(AlarmManager.RTC_WAKEUP, suthatDay.getTimeInMillis(), pendingIntent);
}
}
}

Answer 1

我正在更新您的接收器。试试看：

public class AlarmReceiver extends BroadcastReceiver {
int notificationID;
private SharedPreferences.Editor editor;
private SharedPreferences.OnSharedPreferenceChangeListener sharedpreflistener;
private SharedPreferences sharedPreferences;
private String MAIN_DATA = "com.xxx.xxx.MAIN";

public void createNotification(Context context, String title,
String text, String bigtext, 
int icon, int i, String channelID,
int color,int[] saatler,int[] dklar) {
NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
NotificationChannel channel = new NotificationChannel(channelID, channelID, NotificationManager.IMPORTANCE_HIGH);
channel.setDescription(channelID);
notificationManager.createNotificationChannel(channel);
}
Intent myintent = new Intent(context, SplashActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, myintent, PendingIntent.FLAG_UPDATE_CURRENT);
NotificationCompat.Builder notification = new NotificationCompat.Builder(context.getApplicationContext(), channelID)
.setSmallIcon(icon)
.setChannelId(channelID)
.setContentIntent(pendingIntent)
.setAutoCancel(true)
.setChannelId(channelID)
.setColor(color)
.setDefaults(Notification.DEFAULT_ALL)
.setWhen(System.currentTimeMillis())
.setContentTitle(title)
.setContentText(text)
.setDefaults(Notification.DEFAULT_LIGHTS | Notification.DEFAULT_SOUND)
.setContentInfo("Info")
.setStyle(new NotificationCompat.BigTextStyle()
.bigText(bigtext));
AlarmHelper alarmHelper=new AlarmHelper();
alarmHelper.helper(context,saatler,dklar);
notificationManager.notify(i, notification);
}
public void waterDataClear(Context context) {
sharedPreferences = context.getSharedPreferences(MAIN_DATA, Context.MODE_PRIVATE);
editor = sharedPreferences.edit();
editor.putFloat(SU_KAYIT,  0.0f);
editor.putBoolean(SU_DIALOG, true);
editor.putInt(SU_ML, 0);
editor.apply();
WaterAlarmClear waterClear=new WaterAlarmClear();
waterClear.alarmClear(context);
}
@Override
public void onReceive(Context context, Intent intent) {
sharedPreferences = context.getSharedPreferences(MAIN_DATA, Context.MODE_PRIVATE);
Bundle extras = intent.getExtras();
notificationID = Objects.requireNonNull(extras).getInt("NotificationID");
if (notificationID == 6) {
createNotification(context, context.getString(R.string.tracker_title),
trackertxt, trackertxt, R.mipmap.ic_launcher, 6,
context.getString(R.string.weight_channel),
context.getResources().getColor(R.color.colorhedef), saatler, dklar);
notificationID = 0;
}

if (notificationID == 10) {
waterDataClear(context);
notificationID = 0;
}
}

Answer 2

如果将其部署到任何操作系统版本<安卓O，那么你将尝试使用一个不存在的api。

NotificationChannel出现在26中，这就是为什么找不到该类的原因。