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Android

Posted by Fuseini Isaac
Fuseini Isaac
Courses Plus Student 2,225 Points

GetIntent is giving me a null pointer and crushing my app ribbit

i want to know if there is another way i can write this code to prevent it from giving me this error. 

mMediaUri = getIntent().getData();
    mFileType = getIntent().getExtras().getString(ParseConstants.KEY_FILE_TYPE);
    mMyMessage = getIntent().getExtras().getString("themessage");

3 Answers

Ben Jakuben
STAFF
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

Can you paste in all the messages in your logcat? Sounds like something is missing.

Fuseini Isaac
PLUS
Fuseini Isaac
Courses Plus Student 2,225 Points
Fuseini Isaac
Fuseini Isaac
Courses Plus Student 2,225 Points

04-18 00:05:29.851 7194-7194/com.instantmedia.swerve W/dalvikvm? threadid=1: thread exiting with uncaught exception (group=0x40d2b2a0) 04-18 00:05:29.867 7194-7194/com.instantmedia.swerve E/AndroidRuntime? FATAL EXCEPTION: main java.lang.RuntimeException: Unable to start activity ComponentInfo{com.instantmedia.swerve/com.instantmedia.swerve.RecipientsActivity}: java.lang.NullPointerException at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2129) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2154) at android.app.ActivityThread.access$700(ActivityThread.java:146) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:4949) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1043) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:810) at dalvik.system.NativeStart.main(Native Method) Caused by: java.lang.NullPointerException at com.instantmedia.swerve.RecipientsActivity.onCreate(RecipientsActivity.java:54) at android.app.Activity.performCreate(Activity.java:5185) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2093)             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2154)             at android.app.ActivityThread.access$700(ActivityThread.java:146)             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1260)             at android.os.Handler.dispatchMessage(Handler.java:99)             at android.os.Looper.loop(Looper.java:137)             at android.app.ActivityThread.main(ActivityThread.java:4949)             at java.lang.reflect.Method.invokeNative(Native Method)             at java.lang.reflect.Method.invoke(Method.java:511)             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1043)             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:810)             at dalvik.system.NativeStart.main(Native Method) Ben Jakuben

Ben Jakuben
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

Okay, if you filter through all those messages you can find the important one:

java.lang.NullPointerException at com.instantmedia.swerve.RecipientsActivity.onCreate(RecipientsActivity.java:54)

So next, paste in your code for RecipientsActivity. Which line is at line 54? Mark it with a comment since we won't have your same line numbers in here.

Fuseini Isaac
PLUS
Fuseini Isaac
Courses Plus Student 2,225 Points
Fuseini Isaac
Fuseini Isaac
Courses Plus Student 2,225 Points

this is my code at line 54

mMediaUri = getIntent().getData();
    //mFileType = getIntent().getExtras().getString(ParseConstants.KEY_FILE_TYPE);
    mMyMessage = getIntent().getExtras().getString("themessage");

Ben Jakuben

Ben Jakuben
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

I'm guessing that the Extra with the key "themessage" is missing or has a slightly different key. First, compare this to where you are putting the "themessage" extra on the Intent. You want to make sure it's the same key going in and coming out here.

Then you could add a line and add a break point and run the debugger. If you add an Intent variable, like this:

mMediaUri = getIntent().getData();
Intent intent = getIntent();
mMyMessage = getIntent().getExtras().getString("themessage");

then you could debug at the "Intent intent" line and take a look at the intent variable itself. You could verify if it has an extra named "themessage" or not.