运行项目时出现错误（无法识别启动活动：未找到默认活动）

Question

i am getting this error while developing my app, every thing works fine suddenly this error happened while run the app and checking the changes, as i told everything works fine suddenly this happen i didn't change anything in Manifest.xml file . , this is the manifest file kindly help me out.

this is the error i am getting

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.habitreminder">

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.READ_CALENDAR" />
    <uses-permission android:name="android.permission.WRITE_CALENDAR" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".OnboardingPackage.OnboardingSlider"
            android:theme="@style/Theme.AppCompat.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    <activity
            android:name=".userhome.UserDashboardActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar"
            android:label="@string/title_activity_user_dashboard">
        </activity>
        <activity
            android:name=".signup.UserCalenderSignupActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar" />
        <activity
            android:name=".signup.UserMapSignupActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar" />
        <activity
            android:name=".signup.UserDetailsSignupActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar" />
        <activity
            android:name=".login.LoginActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar" />
        <activity
            android:name=".LoginSignup.LoginSignupActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar" />
        <activity
            android:name=".MainActivity"
            android:theme="@style/Theme.AppCompat.NoActionBar">
        </activity>
        <meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="AIzaSyCy-z3OoXACHh_MKBLoCPjdNo2ySD1ogU8" />
        <meta-data android:name="com.facebook.sdk.ApplicationId"
            android:value="@string/facebook_app_id"/>

        <activity android:name="com.facebook.FacebookActivity"
            android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
            android:label="@string/app_name" />
        <activity
            android:name="com.facebook.CustomTabActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.DEFAULT" />
                <category android:name="android.intent.category.BROWSABLE" />
                <data android:scheme="@string/fb_login_protocol_scheme" />
            </intent-filter>
        </activity>
        <activity android:name=".ProfileSettings.changeprofilename"
            android:theme="@style/AppThemepopup"/>
    </application>
</manifest>

Answer 1

Is your activity declared in َAndroidManifest like this ?

 <activity android:name=".launchactivity" android:label="@string/title_activity_login" android:windowSoftInputMode="stateHidden" /> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity>

Answer 2

在此处输入图像描述我只是关闭 Android Studio 并删除 2 个文件夹名称缓存和 tmp 并再次启动 Android Studio 并且它工作正常。