Question

我有一个已实现parcelable的类，我想将它传递给另一个活动。

这就是我的理由

public class Result implements Parcelable {

    public static final String TMDB_IMAGE_PATH = "http://image.tmdb.org/t/p/w500";

    @SerializedName("vote_count")
    @Expose
    private Integer voteCount;
    @SerializedName("id")
    @Expose
    private Integer id;
    @SerializedName("video")
    @Expose
    private Boolean video;
    @SerializedName("vote_average")
    @Expose
    private Double voteAverage;
    @SerializedName("title")
    @Expose
    private String title;
    @SerializedName("popularity")
    @Expose
    private Double popularity;
    @SerializedName("poster_path")
    @Expose
    private String posterPath;
    @SerializedName("original_language")
    @Expose
    private String originalLanguage;
    @SerializedName("original_title")
    @Expose
    private String originalTitle;
    @SerializedName("genre_ids")
    @Expose
    private JsonArray genreIds = null;
    @SerializedName("backdrop_path")
    @Expose
    private String backdropPath;
    @SerializedName("adult")
    @Expose
    private Boolean adult;
    @SerializedName("overview")
    @Expose
    private String overview;
    @SerializedName("release_date")
    @Expose
    private String releaseDate;



    public Result(Integer voteCount, Integer id, Boolean video,Double voteAverage ,
                  String title ,Double popularity,String posterPath, String originalLanguage,
                  String originalTitle, JsonArray genreIds,String backdropPath,Boolean adult, String overview,String releaseDate){

        this.voteCount = voteCount;
        this.id = id;
        this.video = video;
        this.voteAverage = voteAverage;
        this.title = title;
        this.popularity = popularity;
        this.posterPath = posterPath;
        this.originalLanguage = originalLanguage;
        this.originalTitle = originalTitle;
        this.genreIds = genreIds;
        this.backdropPath = backdropPath;
        this.adult = adult;
        this.overview = overview;
        this.releaseDate = releaseDate;
    }

    private  Result(Parcel source) {
        this.voteCount = source.readInt();
        this.id = source.readInt();
        this.video = source.readByte() != 0;
        this.voteAverage = source.readDouble();
        this.title = source.readString();
        this.popularity = source.readDouble();
        this.posterPath = source.readString();
        this.originalLanguage = source.readString();
        this.originalTitle = source.readString();
        this.backdropPath = source.readString();
        this.adult = source.readByte() != 0;
        this.overview = source.readString();
        this.releaseDate = source.readString();
    }

    public Integer getVoteCount() {
        return voteCount;
    }

    public void setVoteCount(Integer voteCount) {
        this.voteCount = voteCount;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Boolean getVideo() {
        return video;
    }

    public void setVideo(Boolean video) {
        this.video = video;
    }

    public Double getVoteAverage() {
        return voteAverage;
    }

    public void setVoteAverage(Double voteAverage) {
        this.voteAverage = voteAverage;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Double getPopularity() {
        return popularity;
    }

    public void setPopularity(Double popularity) {
        this.popularity = popularity;
    }

    public String getPosterPath() {
        return TMDB_IMAGE_PATH + posterPath;
    }

    public void setPosterPath(String posterPath) {
        this.posterPath = posterPath;
    }

    public String getOriginalLanguage() {
        return originalLanguage;
    }

    public void setOriginalLanguage(String originalLanguage) {
        this.originalLanguage = originalLanguage;
    }

    public String getOriginalTitle() {
        return originalTitle;
    }

    public void setOriginalTitle(String originalTitle) {
        this.originalTitle = originalTitle;
    }

    public JsonArray getGenreIds() {
        return genreIds;
    }

    public void setGenreIds(JsonArray genreIds) {
        this.genreIds = genreIds;
    }

    public String getBackdropPath() {
        return TMDB_IMAGE_PATH +backdropPath;
    }

    public void setBackdropPath(String backdropPath) {
        this.backdropPath = backdropPath;
    }

    public Boolean getAdult() {
        return adult;
    }

    public void setAdult(Boolean adult) {
        this.adult = adult;
    }

    public String getOverview() {
        return overview;
    }

    public void setOverview(String overview) {
        this.overview = overview;
    }

    public String getReleaseDate() {
        return releaseDate;
    }

    public void setReleaseDate(String releaseDate) {
        this.releaseDate = releaseDate;
    }


    public static final Parcelable.Creator<Result> CREATOR = new Parcelable.Creator<Result>() {
        public Result createFromParcel(Parcel source) {
            Result movie = new Result(source);
            return movie;
        }

        public Result[] newArray(int size) {
            return new Result[size];
        }
    };

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int i) {
        dest.writeString(posterPath);
        dest.writeByte((byte) (adult ? 1 : 0));
        dest.writeString(overview);
        dest.writeString(releaseDate);
        dest.writeInt(id);
        dest.writeString(originalTitle);
        dest.writeString(originalLanguage);
        dest.writeString(title);
        dest.writeString(backdropPath);
        dest.writeDouble(popularity);
        dest.writeInt(voteCount);
        dest.writeByte((byte) (video ? 1 : 0));
        dest.writeDouble(voteAverage);
    }
}

这是我从RecycerView适配器发送Parcelable类的方法

public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.ViewHolder> {
    private List<Result> movies;
    private int rowLayout;
    private Context context;

    public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{


        TextView movieTitle;
        TextView data;
        TextView movieDescription;
        TextView rating;
        ImageView pic;


        public ViewHolder(View itemView) {

            super(itemView);
            itemView.setOnClickListener(this);
            movieTitle = (TextView) itemView.findViewById(R.id.title);
            data = (TextView) itemView.findViewById(R.id.subtitle);
            rating = (TextView) itemView.findViewById(R.id.rating);
            pic = (ImageView) itemView.findViewById(R.id.image_view_pic);
        }


        @Override
        public void onClick(View view) {
            int itemPosition = getAdapterPosition();
            Result movie = movies.get(itemPosition);
            Intent intent = new Intent(view.getContext(), MovieDetailActivity.class);
            intent.putExtra("movieDetails",movie);
           view.getContext().startActivity(intent);
    }
    }



    public MovieAdapter(List<Result> movies, Context context){
        this.movies = movies;
        this.context = context;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_movie, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {

        holder.movieTitle.setText(movies.get(position).getTitle());
        holder.data.setText(movies.get(position).getReleaseDate());
        holder.rating.setText(movies.get(position).getVoteAverage().toString());
        String PictureString = movies.get(position).getPosterPath();
        Picasso.with(context)
                .load(PictureString)
                .placeholder(R.color.colorAccent)
                .into(holder.pic);
    }

    @Override
    public int getItemCount() {
        return movies.size();
    }
}

这是我收到它的地方

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_fragment);
    Intent intent = getIntent();
    Result films = intent.getParcelableExtra("movieDetails");
}

所以这段代码的问题是我在接收结束时得到一个空值，但我的Recycler视图正在显示数据。有人能指出我的问题吗？

Answer 1

写入数据和阅读数据的顺序应该相同。在writeToParcel()时，您首先要写posterPath

   @Override
public void writeToParcel(Parcel dest, int i) {
    dest.writeString(posterPath);
    ....
}

然后从Parcel阅读时，您应该先阅读它。如下所示：

    private  Result(Parcel source) {
    this.posterPath = source.readString();
    ...
}

等等。

Answer 2

//我们的属性类型名称

public class Property implements Parcelable {
  ...
}

//在意图

中发送我们的parcelable模型类

Intent intent = new Intent(getActivity(), MainActivity.class);
intent.putExtra("Property", property);
startActivity(intent);

//收集我们的意图

Intent intent = getIntent();
Property property = intent.getParcelableExtra("Property");

接收null Parcelable对象

2 个答案: