在下面的代码中，我从json响应中获取imageUrl为null。因此应用程序崩溃了。这是代码 的片段
public class ReviewFragment extends BaseFragment {
private ListView mListView;
private ViewSwitcher mEmptyView;
private ReviewAdapter mReviewAdapter;
private List<Review> reviews;
@Override
protected String getScreenName() {
return "Reviews";
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_my_review, null);
enableToolbar(true, view, getString(R.string.label_my_reviews));
mReviewAdapter = new ReviewAdapter(getContext(), R.layout.view_review_list_item);
mListView = (ListView) view.findViewById(R.id.list);
mEmptyView = (ViewSwitcher) view.findViewById(R.id.empty);
getLoaderManager().initLoader(1, null, mMyReviewCallback);
mListView.setAdapter(mReviewAdapter);
return view;
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
}
private LoaderManager.LoaderCallbacks<List<Review>> mMyReviewCallback =
new LoaderManager.LoaderCallbacks<List<Review>>() {
@Override
public Loader<List<Review>> onCreateLoader(int id, Bundle args) {
mEmptyView.setDisplayedChild(0);
mEmptyView.setVisibility(View.VISIBLE);
return new Review.MyReviewLoader(getActivity());
}
@Override
public void onLoadFinished(Loader<List<Review>> loader, List<Review> data) {
updateReviews(data);
}
@Override
public void onLoaderReset(Loader<List<Review>> loader) {
}
};
private void updateReviews(List<Review> reviewList) {
if (reviewList.size() > 0) {
mEmptyView.setVisibility(View.GONE);
mReviewAdapter.clear();
this.reviews = reviewList;
if (reviews.size() == 0) {
mEmptyView.setDisplayedChild(1);
mEmptyView.setVisibility(View.VISIBLE);
} else {
mReviewAdapter.clear();
mReviewAdapter.addAll(reviews);
}
} else {
mEmptyView.setDisplayedChild(1);
mEmptyView.setVisibility(View.VISIBLE);
}
}}
适配器
class ReviewAdapter extends ArrayAdapter<Review> {
private static final String TAG = "ReviewAdapter";
private final int mResourceId;
ReviewAdapter(Context context, int resource) {
super(context, resource);
mResourceId = resource;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Holder holder;
if (convertView == null) {
convertView = View.inflate(getContext(), mResourceId, null);
holder = new Holder(convertView);
} else {
holder = (Holder) convertView.getTag();
}
bindView(holder, position);
return convertView;
}
private void bindView(Holder holder, int position) {
final Review review = getItem(position);
Uri imageUri = review.getImageUri(Review.IMAGE_SQ,Beco.getApp().getDensity());
ImageRequest request = ImageRequestBuilder.newBuilderWithSource(imageUri)
.setProgressiveRenderingEnabled(true)
.build();
DraweeController controller = Fresco.newDraweeControllerBuilder()
.setImageRequest(request)
.setOldController(holder.storeLogo.getController())
.build();
GenericDraweeHierarchyBuilder builder =
new GenericDraweeHierarchyBuilder(getContext().getResources());
GenericDraweeHierarchy hierarchy = builder
.setFadeDuration(200)
.setPlaceholderImage(ContextCompat.getDrawable(getContext(), R.drawable.image_deal_default))
.build();
holder.storeLogo.setHierarchy(hierarchy);
holder.storeLogo.setController(controller);
holder.background.setBackgroundColor(review.getColor());
holder.storeName.setText(review.getName());
holder.postedOn.setText(review.getCommentedOn());
holder.comment.setText(review.getComments());
holder.rating.setRating(review.getRating());
}
private class Holder {
SimpleDraweeView storeLogo;
FrameLayout background;
TextView storeName;
TextView postedOn;
RatingBar rating;
TextView comment;
Holder(View convertView) {
convertView.setTag(this);
storeLogo = (SimpleDraweeView) convertView.findViewById(R.id.store_logo);
storeName = (TextView) convertView.findViewById(R.id.store_name);
postedOn = (TextView) convertView.findViewById(R.id.posted_on);
comment = (TextView) convertView.findViewById(R.id.comment);
rating = (RatingBar) convertView.findViewById(R.id.rating);
background = (FrameLayout) convertView.findViewById(R.id.store_background);
}
}}
模型类
public class Review {
public static final String IMAGE_SQ = "_sq";
private static final String DEFAULT_STORE_COLOR = "FFFFFFFF";
private String user;
private String[] imageUrl;
private String name;
private int rating;
private String comments;
private String commentedOn;
private String color;
public String getUser() {
return user;
}
imageUrl[1]));
}
return null;
}
@ColorInt
public int getColor() {
if (color.length() < 6)
color = DEFAULT_STORE_COLOR;
String colorString = color.substring(0, 6);
String alphaString = color.substring(6);
if (alphaString.length() == 0) {
alphaString = "FF";
}
int colorValue = Integer.parseInt(colorString, 16);
int alphaValue = Integer.parseInt(alphaString, 16);
return Color.argb(alphaValue, Color.red(colorValue), Color.green(colorValue), Color.blue(colorValue));
}
public void setUser(String user) {
this.user = user;
}
public int getRating() {
return rating;
}
public void setRating(int rating) {
this.rating = rating;
}
public String getComments() {
return comments;
}
public void setComments(String comments) {
this.comments = comments;
}
public String getCommentedOn() {
return commentedOn;
}
public void setCommentedOn(String commentedOn) {
this.commentedOn = commentedOn;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public static class MyReviewLoader extends ModelListLoader<Review> {
public MyReviewLoader(Context context) {
super(context);
}
@Override
public List<Review> fetch() {
return BecoApi.getClient().getReviews();
}
}}
这是 stacktrace
FATAL EXCEPTION: main
Process: com.beco.ibeco, PID: 9950
java.lang.NullPointerException
at com.facebook.common.internal.Preconditions.checkNotNull(Preconditions.java:210)
at com.facebook.imagepipeline.request.ImageRequestBuilder.setSource(ImageRequestBuilder.java:110)
at com.facebook.imagepipeline.request.ImageRequestBuilder.newBuilderWithSource(ImageRequestBuilder.java:53)
at com.beco.ibeco.app.account.ReviewAdapter.bindView(ReviewAdapter.java:56)
at com.beco.ibeco.app.account.ReviewAdapter.getView(ReviewAdapter.java:48)
at android.widget.AbsListView.obtainView(AbsListView.java:2346)
at android.widget.ListView.measureHeightOfChildren(ListView.java:1281)
at android.widget.ListView.onMeasure(ListView.java:1188)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:700)
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:767)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18811)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:716)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:462)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:135)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at com.android.internal.policy.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2645)
at android.view.View.measure(View.java:18811)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2127)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1243)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1479)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1134)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6045)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:860)
at android.view.Choreographer.doCallbacks(Choreographer.java:672)
at android.
从这个Adapter类中，调试期间获取的Uri imageUri的值为null？请帮助我
答案 0 :(得分：1)
尝试将String[] imageUrl;的字段更改为ArrayList<String> imageUrl = new ArrayList<>();