ActivityNotFoundException：无法找到显式活动类？

Question

Yes, I know that this question has been asked so many times, but none of the answers actually work for me? I think maybe someone just needs to interpret my code.

My application launches on a SplashScreen.java for 10 seconds, and then should load MainActivity.java . However, when I run my application, it launches the SplashScreen but then after 10 seconds, MainActivity does not load and the app say's it has stopped.

I checked the run log, and it say's "android.content.ActivityNotFoundException: Unable to find explicit activity class {com.msp.supercarsounds/com.msp.supercarsounds.MainActivity}; have you declared this activity in your AndroidManifest.xml?"

AndroidManifest.xml:

 <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.msp.supercarsounds"> <uses-sdk android:minSdkVersion="17" android:targetSdkVersion="22"/> <uses-permission android:name="android.permission.INTERNET"/> <application android:largeHeap="true" android:allowBackup="true" android:icon="@mipmap/carsounds_logo" android:label="@string/app_name" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name="com.msp.supercarsounds.SplashScreen" android:theme="@style/Theme.AppCompat.Light.NoActionBar"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <activity android:name="com.msp.supercarsounds.MainActivity" /> <activity android:name=".AudiPrimary" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.RegisterApplication" android:label="Register Appliction" android:theme="@style/AppTheme" /> <activity android:name="com.msp.supercarsounds.Porsche" android:label="Porsche" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.MercedesBenz" android:label="Mercedes-Benz" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.Lamborghini" android:label="Lamborghini" android:theme="@style/AppTheme" /> <activity android:name="com.msp.supercarsounds.Ferrari" android:label="Ferrari" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.BMW" android:label="BMW" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.Jaguar" android:label="Jaguar" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.AstonMartin" android:label="Aston Martin" android:theme="@style/AppTheme" /> <activity android:name="com.msp.supercarsounds.ChooseManufacturer" android:label="Choose Manufacturer" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.Audi" android:label="Audi" android:theme="@style/Theme.AppCompat.Light.NoActionBar" /> <activity android:name="com.msp.supercarsounds.About" android:label="About" android:theme="@style/AppTheme" /> <activity android:name="com.msp.supercarsounds.Contact" android:label="Contact" android:theme="@style/AppTheme" /> <service android:name=".MyFirebaseMessagingService"> <intent-filter> <action android:name="com.google.firebase.MESSAGING.EVENT"/> </intent-filter> </service> <service android:name=".MyFirebaseInstanceIDService"> <intent-filter> <action android:name="com.google.firebase.INSTANCE.ID.EVENT"/> </intent-filter> </service> </manifest> 

SplashScreen.java:

 package com.msp.supercarsounds; import android.content.Intent; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; public class SplashScreen extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.splash_screen_layout); Thread myThread = new Thread() { @Override public void run() { try { sleep(10000); Intent startMainActivity = new Intent(getApplicationContext(), MainActivity.class); startActivity(startMainActivity); finish(); } catch (InterruptedException e) { e.printStackTrace(); } } }; myThread.start(); } } 

MainActivity.java:

 package com.msp.supercarsounds; import android.content.DialogInterface; import android.content.Intent; import android.content.SharedPreferences; import android.support.v7.app.AlertDialog; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.text.Html; import android.view.LayoutInflater; import android.view.MenuItem; import android.view.View; import android.widget.CheckBox; public class MainActivity extends AppCompatActivity { public static final String PREFS_NAME = "MyPrefsFile1"; public CheckBox dontShowAgain; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } public void clickedAbout(View view) { final int result = 1; Intent AboutButtonClicked = new Intent (this, About.class); AboutButtonClicked.putExtra("About", "MainActivity"); startActivityForResult(AboutButtonClicked, result); } public void clickedContact(View view) { final int result = 1; Intent ContactButtonClicked = new Intent (this, Contact.class); ContactButtonClicked.putExtra("Contact", "MainActivity"); startActivityForResult(ContactButtonClicked, result); } @Override protected void onResume() { AlertDialog.Builder adb = new AlertDialog.Builder(this); LayoutInflater adbInflater = LayoutInflater.from(this); View eulaLayout = adbInflater.inflate(R.layout.checkbox, null); SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0); String skipMessage = settings.getString("skipMessage", "NOT checked"); dontShowAgain = (CheckBox) eulaLayout.findViewById(R.id.skip); adb.setView(eulaLayout); adb.setTitle("PLEASE REGISTER THIS APPLICATION!"); adb.setMessage(Html.fromHtml("Please register this application in order to receive newer versions and support!")); adb.setPositiveButton("I understand", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { String checkBoxResult = "NOT checked"; if (dontShowAgain.isChecked()) { checkBoxResult = "checked"; } SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0); SharedPreferences.Editor editor = settings.edit(); editor.putString("skipMessage", checkBoxResult); editor.commit(); // Do what you want to do on "OK" action return; } }); adb.setNegativeButton("Cancel", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int which) { String checkBoxResult = "NOT checked"; if (dontShowAgain.isChecked()) { checkBoxResult = "checked"; } SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0); SharedPreferences.Editor editor = settings.edit(); editor.putString("skipMessage", checkBoxResult); editor.commit(); return; } }); if (!skipMessage.equals("checked")) { adb.show(); } super.onResume(); } public void clickedSettings(MenuItem item) { final int result = 1; Intent SettingsButtonClicked = new Intent (this, About.class); SettingsButtonClicked.putExtra("About", "MainActivity"); startActivityForResult(SettingsButtonClicked, result); } public void clickedSupercarSounds(View view) { final int result = 1; Intent SupercarSoundsButtonClicked = new Intent (this, ChooseManufacturer.class); SupercarSoundsButtonClicked.putExtra("Choose Manufacturer", "MainActivity"); startActivityForResult(SupercarSoundsButtonClicked, result); } public void clickedRegisterApplication(View view) { final int result = 1; Intent RegisterApplicationButtonClicked = new Intent (this, RegisterApplication.class); RegisterApplicationButtonClicked.putExtra("Register Application", "MainActivity"); startActivityForResult(RegisterApplicationButtonClicked, result); } } 

Thanks!

Answer 1

您需要将<activity>标签放置在AndroidManifest.xml的<application>标签中。