我是Android编程新手，我正在从一个大书呆子牧场指南到android编程的项目。我发布了几天前我遇到的一个问题，事实证明我在调试过程中犯了一些非常明显的错误。我在这个网站上向我指出了这一点。不幸的是，我仍然不清楚我的问题的解决方案。会发生什么事情，当我点击我的recyclerview中的一个项目时，该应用程序会给我一个弹出窗口，说明它已停止。应该发生的是一个包含单个片段的新活动应该启动。在调试器中单步执行我的代码后，当我调用newIntent（）方法时，我发现了一个空指针。然而从我可以看到它看起来所有的变量都被定义，只有当我点击步骤一直到Bundle（）构造函数，我看到一条消息“方法抛出'java.lang.NullPointerException'异常无法评估android.os.Bundle.toString（）“。所以我猜这是由某个地方的Intent（）构造函数调用的？显然，它是Bundle.java中的第50行抛出异常。
至于我的代码，我也在这里发布。这是CrimeListActivity.java：
这里是CrimeListFragment：
package com.bignerdranch.android.criminalintent;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.NavUtils;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.view.menu.ExpandedMenuView;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.IllegalFormatCodePointException;
import java.util.List;
public class CrimeListFragment extends Fragment{
private RecyclerView mCrimeRecyclerView;
private CrimeAdapter mAdapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View view = inflater.inflate(R.layout.fragment_crime_list, container, false);
mCrimeRecyclerView = (RecyclerView) view.findViewById(R.id.crime_recycler_view);
mCrimeRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
updateUI();
return view;
}//end onCreate
private void updateUI(){
CrimeLab crimeLab = CrimeLab.get(getActivity()); //workds here but not in crimeFragment
List<Crime> crimes = crimeLab.getCrimes();
if (mAdapter == null){
mAdapter = new CrimeAdapter(crimes);
mCrimeRecyclerView.setAdapter(mAdapter);
}else {
mAdapter.notifyDataSetChanged();
}
}//end updateUI()
private class CrimeHolder extends RecyclerView.ViewHolder implements
View.OnClickListener{
private TextView mTitleTextView;
private TextView mDateTextView;
private Crime mCrime;
private ImageView mSolvedImageView;
@Override
public void onClick(View view){
try {
Intent intent = CrimePagerActivity.newIntent(getActivity(), mCrime.getId()); // this is the line i set the breakpoint and stepped into
startActivity(intent);
}catch(Exception e){
Log.d("ONCLICK", e.toString());
}
}//end onCLick()
public CrimeHolder(LayoutInflater inflater, ViewGroup parent){
super(inflater.inflate(R.layout.list_item_crime, parent, false));
itemView.setOnClickListener(this);
mTitleTextView = (TextView) itemView.findViewById(R.id.crime_title);
mDateTextView = (TextView) itemView.findViewById(R.id.crime_date);
mSolvedImageView = (ImageView) itemView.findViewById(R.id.crime_solved);
}//end constructor
public void bind(Crime crime){
mCrime = crime;
mTitleTextView.setText(crime.getTitle());
mDateTextView.setText(mCrime.getDate().toString());
mSolvedImageView.setVisibility(crime.isSolved() ? View.VISIBLE : View.GONE);
}//end bind()
}//end CrimeHolder inner Class
private class CrimeAdapter extends RecyclerView.Adapter<CrimeHolder>{
private List<Crime> mCrimes;
public CrimeAdapter(List<Crime> crimes){
mCrimes = crimes;
}//end constructor
@Override
public CrimeHolder onCreateViewHolder(ViewGroup parent, int viewType){
LayoutInflater layoutInflater = LayoutInflater.from(getActivity());
return new CrimeHolder(layoutInflater, parent);
}// end onCreateViewHolder
@Override
public void onBindViewHolder(CrimeHolder holder, int position){
Crime crime = mCrimes.get(position);
holder.bind(crime);
}
@Override
public int getItemCount(){
return mCrimes.size();
}
}//end CrimeAdapter inner Class
}//end CrimeListFragment class
这里是Crime类和CrimeLab类
package com.bignerdranch.android.criminalintent;
import java.util.Date;
import java.util.UUID;
public class Crime {
public UUID getId() {
return mId;
}
public String getTitle() {
return mTitle;
}
public Date getDate() {
return mDate;
}
public boolean isSolved() {
return mSolved;
}
public void setTitle(String title) {
mTitle = title;
}
public void setDate(Date date) {
mDate = date;
}
public void setSolved(boolean solved) {
mSolved = solved;
}
private UUID mId;
private String mTitle;
private Date mDate;
private boolean mSolved;
public Crime(){
mId = UUID.randomUUID();
mDate = new Date();
}
}
package com.bignerdranch.android.criminalintent;
import android.content.Context;
import java.util.ArrayList;
import java.util.List ;
import java.util.UUID;
public class CrimeLab {
private static CrimeLab sCrimeLab;
private List<Crime> mCrimes;
public static CrimeLab get(Context context){
if(sCrimeLab == null){
sCrimeLab = new CrimeLab(context);
}
return sCrimeLab;
}//end get()
private CrimeLab(Context context){
}//end constructor
public List<Crime> getCrimes(){
mCrimes = new ArrayList<>();
for (int i = 0; i < 100; i++){
Crime crime = new Crime();
crime.setTitle("Crime #" + i);
crime.setSolved(i % 2 == 0); //every other crime will be checked!
mCrimes.add(crime);
}
return mCrimes;
}//end getCrimes
public Crime getCrime(UUID id){
for (Crime crime : mCrimes){
if (crime.getId().equals(id)){
return crime;
}
}
return null;
}//end getCrime()
}//end CrimeLab class
最后但并非最不重要的是CrimePagerActivity类：
public class CrimePagerActivity extends AppCompatActivity {
private static final String EXTRA_CRIME_ID =
“com.bignerdranch.android.criminalintent.crime_id”;
private ViewPager mViewPager;
private List<Crime> mCrimes;
public static Intent newIntent(Context packageContext, UUID crimeId){
Intent intent = new Intent(packageContext, CrimePagerActivity.class);
intent.putExtra(EXTRA_CRIME_ID, crimeId);
return intent;
}
@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_crime_pager);
UUID crimeId = (UUID) getIntent().getSerializableExtra(EXTRA_CRIME_ID);
mViewPager = (ViewPager) findViewById(R.id.crime_view_pager);
mCrimes = CrimeLab.get(this).getCrimes();
FragmentManager fragmentManager = getSupportFragmentManager();
mViewPager.setAdapter(new FragmentStatePagerAdapter(fragmentManager) {
@Override
public Fragment getItem(int position) {
Crime crime = mCrimes.get(position);
return CrimeFragment.newInstance(crime.getId());
}
@Override
public int getCount() {
return mCrimes.size();
}
});
}// end onCreate()
}//end crimePagerAtivity class
当我进入对CrimePagerActivity.newIntent（）的调用时，我最终到达定义方法的行，但是当我不断进入代码时，我最终会到Bundle（）调用的Bundle.java中的行super（），显然是抛出nullpointerexception的地方。不确定我是否只是在某个地方犯了一些愚蠢的错误，但我无法弄明白。如果您发现任何错误或指出我正确的方向，请告诉我。感谢。
这是堆栈跟踪：
05-02 19:32:42.220 8395-8395/com.bignerdranch.android.criminalintent E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.bignerdranch.android.criminalintent, PID: 8395
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.bignerdranch.android.criminalintent.Crime.getTitle()' on a null object reference
at com.bignerdranch.android.criminalintent.CrimeFragment.onCreateView(CrimeFragment.java:51)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:2192)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1299)
at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1528)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1595)
at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:758)
at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2363)
at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2149)
at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2103)
at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:1984)
at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:626)
at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:166)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1268)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1116)
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1642)
at android.view.View.measure(View.java:19857)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139)
at android.view.View.measure(View.java:19857)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
at android.support.v7.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:393)
at android.view.View.measure(View.java:19857)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at android.view.View.measure(View.java:19857)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
at android.view.View.measure(View.java:19857)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
at com.android.internal.policy.DecorView.onMeasure(DecorView.java:689)
at android.view.View.measure(View.java:19857)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2275)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1366)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1619)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1254)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6337)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:874)
at android.view.Choreographer.doCallbacks(Choreographer.java:686)
at android.view.Choreographer.doFrame(Choreographer.java:621)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
at android.os.Handler.handleCallback(Handler.java:751)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
这里也是CrimeFragment类：
package com.bignerdranch.android.criminalintent;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.view.LayoutInflaterCompat;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import java.util.UUID;
import static com.bignerdranch.android.criminalintent.CrimePagerActivity.EXTRA_CRIME_ID;
public class CrimeFragment extends Fragment{
private static final String ARG_CRIME_ID = "crimeId";
private Crime mCrime;
private UUID crimeId;
private EditText mTitleField;
private Button mDateButton;
private CheckBox mSolvedCheckBox;
/* public static CrimeFragment newInstance(UUID crimeId){
Bundle args = new Bundle();
args.putSerializable(ARG_CRIME_ID, crimeId);
args.getSerializable(EXTRA_CRIME_ID);
CrimeFragment fragment = new CrimeFragment();
fragment.setArguments(args);
return fragment;
}*/
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
UUID crimeID = (UUID) getActivity().getIntent().getSerializableExtra(EXTRA_CRIME_ID);
mCrime = CrimeLab.get(getActivity()).getCrime(crimeID);
}//end onCreate()
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View v = inflater.inflate(R.layout.fragment_crime, container, false);
mTitleField = (EditText) v.findViewById(R.id.crime_title);
mTitleField.setText(mCrime.getTitle()); // <-------- NULL pointer here
mTitleField.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
mCrime.setTitle(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
}
});//end textChangedListener
mSolvedCheckBox = (CheckBox) v.findViewById(R.id.crime_solved);
mSolvedCheckBox.setChecked(mCrime.isSolved());
mSolvedCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
mCrime.setSolved(isChecked);
}
});//end checkedchangedlistener
mDateButton = (Button) v.findViewById(R.id.crime_date);
mDateButton.setText(mCrime.getDate().toString());
mDateButton.setEnabled(false);
return v;
}//end onCreateView()
}//end class
这是包含mCrimes列表数据的日志：
05-03 18:48:27.663 5991-5991/com.bignerdranch.android.criminalintent D/mCrimes: [com.bignerdranch.android.criminalintent.Crime@3a456fd, com.bignerdranch.android.criminalintent.Crime@4284ff2, com.bignerdranch.android.criminalintent.Crime@4b1f643, com.bignerdranch.android.criminalintent.Crime@3a074c0, com.bignerdranch.android.criminalintent.Crime@b6465f9, com.bignerdranch.android.criminalintent.Crime@867793e, com.bignerdranch.android.criminalintent.Crime@ef3b39f, com.bignerdranch.android.criminalintent.Crime@a781cec, com.bignerdranch.android.criminalintent.Crime@87c68b5, com.bignerdranch.android.criminalintent.Crime@5ddeb4a, com.bignerdranch.android.criminalintent.Crime@269eabb, com.bignerdranch.android.criminalintent.Crime@4401bd8, com.bignerdranch.android.criminalintent.Crime@8d7db31, com.bignerdranch.android.criminalintent.Crime@1977216, com.bignerdranch.android.criminalintent.Crime@5427797, com.bignerdranch.android.criminalintent.Crime@3871d84, com.bignerdranch.android.criminalintent.Crime@39df96d, com.bignerdranch.android.criminalintent.Crime@39099a2, com.bignerdranch.android.criminalintent.Crime@8acf633, com.bignerdranch.android.criminalintent.Crime@31a8df0, com.bignerdranch.android.criminalintent.Crime@12dbf69, com.bignerdranch.android.criminalintent.Crime@502adee, com.bignerdranch.android.criminalintent.Crime@736c28f, com.bignerdranch.android.criminalintent.Crime@b32991c, com.bignerdranch.android.criminalintent.Crime@6d9e925, com.bignerdranch.android.criminalintent.Crime@76fbafa, com.bignerdranch.android.criminalintent.Crime@ce6f8ab, com.bignerdranch.android.criminalintent.Crime@d5e2b08, com.bignerdranch.android.criminalintent.Crime@264f2a1, com.bignerdranch.android.criminalintent.Crime@6e8cc6, com.bignerdranch.android.criminalintent.Crime@51a7487, com.bignerdranch.android.criminalintent.Crime@32eefb4, com.bignerdranch.android.criminalintent.Crime@13d17dd, com.bignerdranch.android.criminalintent.Crime@636af52, com.bignerdranch.android.criminalintent.Crime@a1fd223, com.bignerdranch.android.criminalintent.Crime@ba55320, com.bignerdranch.android.criminalintent.Crime@f7854d9, com.bignerdranch.android.criminalintent.Crime@8ec6e9e, com.bignerdranch.android.criminalintent.Crime@2936d7f, com.bignerdranch.android.criminalintent.Crime@35c814c, com.bignerdranch.android.criminalintent.Crime@a906595, com.bignerdranch.android.criminalintent.Crime@4acd6aa, com.bignerdranch.android.criminalintent.Crime@87b629b, com.bignerdranch.android.criminalintent.Crime@3766638, com.bignerdranch.android.criminalintent.Crime@3dec611, com.bignerdranch.android.criminalintent.Crime@859b376, com.bignerdranch.android.criminalintent.Crime@6238d77, com.bignerdranch.android.criminalintent.Crime@347ade4, com.bignerdranch.android.criminalintent.Crime@ed8b24d, com.bignerdranch.android.criminalintent.Crime@d259102, com.bignerdranch.android.criminalintent.Crime@4b98a13, com.bignerdranch.android.criminalintent.Crime@8c3c450, com.bignerdranch.android.criminalintent.Crime@70b2649, com.bignerdranch.android.criminalintent.Crime@adfbb4e, com.bignerdranch.android.criminalintent.Crime@8a8b46f, com.bignerdranch.android.criminalintent.Crime@3a8d57c, com.bignerdranch.android.criminalintent.Crime@9d6de05, com.bignerdranch.android.criminalintent.Crime@5003e5a, com.bignerdranch.android.criminalintent.Crime@7b6288b, com.bignerdranch.android.criminalintent.Crime@f6bcd68, com.bignerdranch.android.criminalintent.Crime@fec5581, com.bignerdranch.android.criminalintent.Crime@c73e626, com.bignerdranch.android.criminalintent.Crime@4dcc267, com.bignerdranch.android.criminalintent.Crime@7e45814, com.bignerdranch.android.criminalintent.Crime@287c8bd, com.bignerdranch.android.criminalintent.Crime@2283eb2, com.bignerdranch.android.criminalintent.Crime@de91e03, com.bignerdranch.android.criminalintent.Crime@cb8e180, com.bignerdranch.android.criminalintent.Crime@86d33b9, com.bignerdranch.android.criminalintent.Crime@65793fe, com.bignerdranch.android.criminalintent.Crime@6d5975f, com.bignerdranch.android.criminalintent.Crime@f8a95ac, com.bignerdranch.android.criminalintent.Crime@6a45275, com.bignerdranch.android.criminalintent.Cri
05-03 18:48:35.962 5991-5991/com.bignerdranch.android.criminalintent D/mCrimes: [com.bignerdranch.android.criminalintent.Crime@823ce6c, com.bignerdranch.android.criminalintent.Crime@3abfc35, com.bignerdranch.android.criminalintent.Crime@d10b8ca, com.bignerdranch.android.criminalintent.Crime@ea86a3b, com.bignerdranch.android.criminalintent.Crime@2b56558, com.bignerdranch.android.criminalintent.Crime@62d26b1, com.bignerdranch.android.criminalintent.Crime@e99796, com.bignerdranch.android.criminalintent.Crime@3a96f17, com.bignerdranch.android.criminalintent.Crime@1c77f04, com.bignerdranch.android.criminalintent.Crime@bbc7ced, com.bignerdranch.android.criminalintent.Crime@99f9722, com.bignerdranch.android.criminalintent.Crime@f4be5b3, com.bignerdranch.android.criminalintent.Crime@ebf8770, com.bignerdranch.android.criminalintent.Crime@370fae9, com.bignerdranch.android.criminalintent.Crime@cc4036e, com.bignerdranch.android.criminalintent.Crime@d952a0f, com.bignerdranch.android.criminalintent.Crime@1edaa9c, com.bignerdranch.android.criminalintent.Crime@cd55ca5, com.bignerdranch.android.criminalintent.Crime@5b0e87a, com.bignerdranch.android.criminalintent.Crime@b84582b, com.bignerdranch.android.criminalintent.Crime@678d488, com.bignerdranch.android.criminalintent.Crime@b641e21, com.bignerdranch.android.criminalintent.Crime@9551246, com.bignerdranch.android.criminalintent.Crime@cee4c07, com.bignerdranch.android.criminalintent.Crime@10ab134, com.bignerdranch.android.criminalintent.Crime@5c37b5d, com.bignerdranch.android.criminalintent.Crime@ac00cd2, com.bignerdranch.android.criminalintent.Crime@419a1a3, com.bignerdranch.android.criminalintent.Crime@53baca0, com.bignerdranch.android.criminalintent.Crime@cc17059, com.bignerdranch.android.criminalintent.Crime@c6e241e, com.bignerdranch.android.criminalintent.Crime@71ab4ff, com.bignerdranch.android.criminalintent.Crime@5bef2cc, com.bignerdranch.android.criminalintent.Crime@60fb915, com.bignerdranch.android.criminalintent.Crime@a54642a, com.bignerdranch.android.criminalintent.Crime@eefa21b, com.bignerdranch.android.criminalintent.Crime@b4e6fb8, com.bignerdranch.android.criminalintent.Crime@6bfd191, com.bignerdranch.android.criminalintent.Crime@8ac98f6, com.bignerdranch.android.criminalintent.Crime@c5c44f7, com.bignerdranch.android.criminalintent.Crime@e56cf64, com.bignerdranch.android.criminalintent.Crime@97ef5cd, com.bignerdranch.android.criminalintent.Crime@3814e82, com.bignerdranch.android.criminalintent.Crime@e863993, com.bignerdranch.android.criminalintent.Crime@f637dd0, com.bignerdranch.android.criminalintent.Crime@c9221c9, com.bignerdranch.android.criminalintent.Crime@af9d0ce, com.bignerdranch.android.criminalintent.Crime@750dbef, com.bignerdranch.android.criminalintent.Crime@a4aa6fc, com.bignerdranch.android.criminalintent.Crime@3921185, com.bignerdranch.android.criminalintent.Crime@8662bda, com.bignerdranch.android.criminalintent.Crime@979480b, com.bignerdranch.android.criminalintent.Crime@1936e8, com.bignerdranch.android.criminalintent.Crime@8e74101, com.bignerdranch.android.criminalintent.Crime@80b2ba6, com.bignerdranch.android.criminalintent.Crime@c7259e7, com.bignerdranch.android.criminalintent.Crime@3bed994, com.bignerdranch.android.criminalintent.Crime@b05ec3d, com.bignerdranch.android.criminalintent.Crime@3ae5c32, com.bignerdranch.android.criminalintent.Crime@200ad83, com.bignerdranch.android.criminalintent.Crime@579fb00, com.bignerdranch.android.criminalintent.Crime@16a0f39, com.bignerdranch.android.criminalintent.Crime@9e2097e, com.bignerdranch.android.criminalintent.Crime@9969edf, com.bignerdranch.android.criminalintent.Crime@903c72c, com.bignerdranch.android.criminalintent.Crime@55365f5, com.bignerdranch.android.criminalintent.Crime@e113f8a, com.bignerdranch.android.criminalintent.Crime@d7049fb, com.bignerdranch.android.criminalintent.Crime@27c2a18, com.bignerdranch.android.criminalintent.Crime@a416c71, com.bignerdranch.android.criminalintent.Crime@d4bca56, com.bignerdranch.android.criminalintent.Crime@56f8ad7, com.bignerdranch.android.criminalintent.Crime@615cfc4, com.bignerdranch.android.criminalintent.Crim
答案 0 :(得分：0)
以下函数中您的犯罪对象为空：
public void bind(Crime crime){
mCrime = crime;
mTitleTextView.setText(crime.getTitle());
mDateTextView.setText(mCrime.getDate().toString());
mSolvedImageView.setVisibility(crime.isSolved() ? View.VISIBLE : View.GONE);
}
答案 1 :(得分：0)
我终于能够解决这个问题......虽然不是最专业的方式......我所做的是删除整个项目并从头开始。不知道我做错了什么，但现在工作正常。感谢@ R.M.M和其他人的帮助。