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Royce Foo Wai Kit
2,551 PointsI keep getting bugs/errors relating to the save instance and restore instance.
No matter what i change it'll still pop up different kind of errors or bug even if i follow the video step by step. Sorry for the complications i tried following the instructions given by the markdown cheatsheet but still don't even know how to post a proper question.
public class Funfactactivity extends AppCompatActivity {
public static final String TAG = Funfactactivity.class.getSimpleName();
private static final String KEY_FACT = "KEY_FACT";
private static final String KEY_COLOR = "KEY_COLOR";
//Declare our view variables
private FactBook mFactBook = new FactBook();
private ColorWheel mColorWheel = new ColorWheel();
private TextView mfunfacttext;
private Button mfunfactbutton;
private RelativeLayout mRelativeLayout;
private String mFact = mFactBook.mFacts[0];
private int mColor = Color.parseColor(mColorWheel.mColors[8]);
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putString(KEY_FACT, mFact);
outState.putInt(KEY_COLOR, mColor);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
mFact=savedInstanceState.getString(KEY_FACT);
mfunfacttext.setText(mFact);
mColor=savedInstanceState.getInt(KEY_COLOR);
mRelativeLayout.setBackgroundColor(mColor);
mfunfactbutton.setTextColor(mColor);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_funfactactivity);
//Assign views from the layout files to the corresponding variables
mfunfacttext = (TextView) findViewById(R.id.funcfacttext);
mfunfactbutton = (Button) findViewById(R.id.funfactbutton);
mRelativeLayout = (RelativeLayout) findViewById(R.id.RelativeLayout);
View.OnClickListener listener = new View.OnClickListener() {
@Override
public void onClick(View v) {
mFact = mFactBook.getFact();
mfunfacttext.setText(mFact);
mColor = mColorWheel.getColor();
//update screen with fact
mRelativeLayout.setBackgroundColor(mColor);
mfunfactbutton.setTextColor(mColor);
}
};
mfunfactbutton.setOnClickListener(listener);
//toast is like invinsible notifcation like android app killer says app killed how many
Toast.makeText(Funfactactivity.this, "Application started", Toast.LENGTH_SHORT).show();
}
}
The error
[ 08-18 07:10:05.630 4108: 4145 D/]
HostConnection::get() New Host Connection established 0xaa9a4ae0, tid 4145
08-18 07:10:05.650 4108-4145/fyp.funfacts I/OpenGLRenderer: Initialized EGL, version 1.4
08-18 07:10:08.873 4108-4145/fyp.funfacts E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb4093b20
08-18 07:10:08.897 4108-4108/fyp.funfacts D/AndroidRuntime: Shutting down VM
08-18 07:10:08.898 4108-4108/fyp.funfacts E/AndroidRuntime: FATAL EXCEPTION: main
Process: fyp.funfacts, PID: 4108
java.lang.RuntimeException: Unable to start activity ComponentInfo{fyp.funfacts/fyp.funfacts.Funfactactivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.RelativeLayout.setBackgroundColor(int)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4077)
at android.app.ActivityThread.-wrap15(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1350)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.RelativeLayout.setBackgroundColor(int)' on a null object reference
at fyp.funfacts.Funfactactivity.onRestoreInstanceState(Funfactactivity.java:45)
at android.app.Activity.performRestoreInstanceState(Activity.java:959)
at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1163)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2389)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4077)
at android.app.ActivityThread.-wrap15(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1350)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Royce Foo Wai Kit
2,551 PointsRoyce Foo Wai Kit
2,551 PointsEdit : Solved.. For people having crashes with their new android studio in Marshmellow android please add the following code: android:configChanges="orientation|screenSize"
in your android manifest files.