i need help. I'm in the finish phase of development of my android application and now after a few month of develop the app magically crash with this error :
java.lang.String android.content.Context.getPackageName()' on a null object reference
I don't know what is the problem but i will post the code that cause the crash :
public static void start(Context context) {
context.startActivity(new Intent(context, ConversationsActivity.class));
}
called with this piece of code (inside a fragment):
ConversationsActivity.start(getActivity());
The last change that i've make was to add Fabric.io ( in particular Branch ) and from the history in the last commit on git i don't show nothing that can produce this error
EDIT :
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Context.getPackageName()' on a null object reference
at android.content.ComponentName.<init>(ComponentName.java:128)
at android.content.Intent.<init>(Intent.java:4900)
at com.exampleapp.views.messages.ConversationsActivity.start(ConversationsActivity.java:31)
at com.exampleapp.views.menu.MenuFragment.onMenuMessagesClicked(MenuFragment.java:116)
at com.exampleapp.views.menu.MenuFragment_ViewBinding$5.doClick(MenuFragment_ViewBinding.java:82)
at butterknife.internal.DebouncingOnClickListener.onClick(DebouncingOnClickListener.java:22)
at android.view.View.performClick(View.java:5637)
at android.view.View$PerformClick.run(View.java:22429)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Or you could do this:
public static void start(Activity activity) {
activity.startActivity(new Intent(activity, ConversationsActivity.class));
}
You should use getActivity()
to launch an Activity
from Fragment
.
From a Fragment: Context
is parent activity (getActivity())
.
Intent intent = new Intent(getActivity(), ConversationsActivity.class);
startActivity(intent);
From an Activity: Context
is current activity (this)
.
Intent intent = new Intent(this, ConversationsActivity.class);
startActivity(intent);
Your problem is that you are using the intent wrong. Replace your start() code with this:
public static void start() {
Intent i = new Intent(getApplicationContext(), ConversationsActivity.class);
startActivity(i);
}
Then instead of using ConversationsActivity.start(getActivity());
to call it, just use start();
when you want to call the method.
Hope this helps!
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