Me aparece el error "Declaración inalcanzable" en Android

android-fragments unreachable-statement

Question

¿Por qué recibo el error de que la línea 92 es una declaración inalcanzable? El error está en esta línea:

final RadioButton r1 = (RadioButton) getView().findViewById(R.id.radio1);

Código:

public class TabFragmentA extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if (container == null) {
return null;
}
return (RelativeLayout) inflater.inflate(R.layout.tab_layout_a, container, false);
final RadioButton r1 = (RadioButton) getView().findViewById(R.id.radio1); //the error is here
final RadioButton r2 = (RadioButton) getView().findViewById(R.id.radio2);
final ImageView iv1 = (ImageView) getView().findViewById(R.id.iv1);
final ImageView iv2 = (ImageView) getView().findViewById(R.id.iv2);
iv1.setVisibility(View.INVISIBLE);
iv2.setVisibility(View.INVISIBLE);
r1.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(r1.isChecked())
{
r2.setChecked(false);
iv2.setVisibility(View.INVISIBLE);
iv1.setVisibility(View.VISIBLE);
}
}
});
r2.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(r2.isChecked())
{
r1.setChecked(false);
iv1.setVisibility(View.INVISIBLE);
iv2.setVisibility(View.VISIBLE);
}
}
});
}
}

Error de logcat:

01-23 02:43:31.082 1903-1903/br.com.eddboytools.PreDim E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: br.com.eddboytools.PreDim, PID: 1903
java.lang.NullPointerException: Attempt to invoke virtual method ''android.view.View android.view.View.findViewById(int)'' on a null object reference
at br.com.eddboytools.PreDim.TabFragmentA.onCreateView(TabFragmentA.java:29)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1478)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:927)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1460)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:472)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1068)
at android.support.v4.view.ViewPager.populate(ViewPager.java:914)
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1436)
at android.view.View.measure(View.java:17430)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:875)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:447)
at android.view.View.measure(View.java:17430)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5463)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:430)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2560)
at android.view.View.measure(View.java:17430)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2001)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1166)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1372)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5779)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
at android.view.Choreographer.doCallbacks(Choreographer.java:580)
at android.view.Choreographer.doFrame(Choreographer.java:550)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
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:5221)
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:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
01-23 02:43:31.094 1903-1915/br.com.eddboytools.PreDim I/art﹕ Background partial concurrent mark sweep GC freed 261(11KB) AllocSpace objects, 0(0B) LOS objects, 27% free, 1328KB/1840KB, paused 20.856ms total 51.174ms

Answer 1

La declaración de devolución debe estar al final:

final RadioButton r1 = (RadioButton) getView().findViewById(R.id.radio1);
final RadioButton r2 = (RadioButton) getView().findViewById(R.id.radio2);
return (RelativeLayout) inflater.inflate(R.layout.tab_layout_a, container, false);

Answer 2

No return declaración de return encima de cualquier otra declaración a menos que esa return esté bajo una declaración condicional. Si hacemos eso, todas las declaraciones a continuación que nunca se ejecutarían (significa que se volvería inalcanzable en todas las circunstancias), lo que causa el error que está recibiendo.

Hazlo asi

public class TabFragmentA extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
RelativeLayout rootView = (RelativeLayout) inflater.inflate(R.layout.tab_layout_a, container, false);
final RadioButton r1 = (RadioButton) rootView.findViewById(R.id.radio1);
final RadioButton r2 = (RadioButton) rootView.findViewById(R.id.radio2);
final ImageView iv1 = (ImageView) rootView.findViewById(R.id.iv1);
final ImageView iv2 = (ImageView) rootView.findViewById(R.id.iv2);
iv1.setVisibility(View.INVISIBLE);
iv2.setVisibility(View.INVISIBLE);
r1.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(r1.isChecked())
{
r2.setChecked(false);
iv2.setVisibility(View.INVISIBLE);
iv1.setVisibility(View.VISIBLE);
}
}
});
r2.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(r2.isChecked())
{
r1.setChecked(false);
iv1.setVisibility(View.INVISIBLE);
iv2.setVisibility(View.VISIBLE);
}
}
});
return rootView;
}
}

Answer 3

Tienes un retorno justo encima de él. Cuando regrese de un método, nada de lo siguiente se ejecutará. Eso significa que la línea de abajo nunca se ejecutará.

El compilador está tratando de ayudarte a ver esto.