Android Studio包名称未解析，无法获取上下文

Question

Made an app, wanted to show a toast but again the sh*tty error popped up saying the context cannot be invoked on a null object reference (yes it's in a different void and yes it's running on the ui thread) I tried adding android:name to the application area in the androidmanifest (package name is noahvt.vremote) and vremote was in red and said that the symbol could not be resolved which is really weird as that is the correct name!

here is a part of my android manifest:

<?xml version="1.0" encoding="utf-8"?>

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>
<application
    android:name="noahvt.vremote" <---- vremote is in red
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/Theme.AppCompat.Light.NoActionBar" >

And here is the non working show toast void i created:

 public void Toasts()
{
    final String RecToast = g.GetToast();

    MainActivity.this.runOnUiThread(new Runnable() {
        @Override
        public void run() {
            final Context context = getApplicationContext();
            Toast.makeText(context , RecToast, Toast.LENGTH_LONG).show();


        }
    });
}

The context is giving a nullpointerexception which leads me to think that it has something to do with the android:name

BTW this is the stacktrace:

java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.Context android.content.Context.getApplicationContext()' on a null object reference
        at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:106)
        at noahvt.vremote.MainActivity$3.run(MainActivity.java:169)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5289)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)
        at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:115)

Answer 1

May this link could help you Android: Including multiple Java Packages to Manifest

Also check the import statement at the top of your activity.