从我正在解析的JSON数组中，我想将一个特定的对象值（使用intent putExtra）发送到另一个活动。我看过这个this question 和接受的答案，但我不想发送所有的值，在我的情况下，我只想将 news_id 作为整数发送到 NewsDetails.class 。
我尝试使用接受的答案来做，但我卡住了。
MainActivity
public class MainActivity extends AppCompatActivity{
private final String TAG = "MainActivity";
//Creating a list of newss
private List<NewsItems> mNewsItemsList;
//Creating Views
private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private ProgressDialog mProgressDialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(TAG, "Device rotated and onCreate called");
//Initializing Views
recyclerView = (RecyclerView) findViewById(R.id.news_recycler);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
//Initializing the newslist
mNewsItemsList = new ArrayList<>();
adapter = new NewsAdapter(mNewsItemsList, this);
recyclerView.setAdapter(adapter);
//Caling method to get data
getData();
}
//This method will get data from the web api
private void getData(){
Log.d(TAG, "getData called");
//Showing progress dialog
mProgressDialog = new ProgressDialog(MainActivity.this);
mProgressDialog.setCancelable(false);
mProgressDialog.setMessage(this.getResources().getString(R.string.load_news));
mProgressDialog.show();
//Creating a json request
JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(ConfigNews.GET_URL,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
Log.d(TAG, "onResponse called");
//Dismissing the progress dialog
if (mProgressDialog != null) {
mProgressDialog.hide();
}
/*progressDialog.dismiss();*/
//calling method to parse json array
parseData(response);
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
});
//Creating request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
//Adding request to the queue
requestQueue.add(jsonArrayRequest);
}
//This method will parse json data
private void parseData(JSONArray array){
Log.d(TAG, "Parsing array");
for(int i = 0; i<array.length(); i++) {
NewsItems newsItem = new NewsItems();
JSONObject jsonObject = null;
try {
jsonObject = array.getJSONObject(i);
newsItem.setNews_title(jsonObject.getString(ConfigNews.TAG_NEWS_TITLE));
newsItem.setNews_excerpt(jsonObject.getString(ConfigNews.TAG_NEWS_EXCERPT));
newsItem.setNewsId(jsonObject.getInt(ConfigNews.TAG_NEWS_ID));
} catch (JSONException w) {
w.printStackTrace();
}
mNewsItemsList.add(newsItem);
}
adapter.notifyItemRangeChanged(0, adapter.getItemCount());
}
@Override
public void onDestroy() {
super.onDestroy();
Log.d(TAG, "onDestroy called");
if (mProgressDialog != null){
mProgressDialog.dismiss();
Log.d(TAG, "mProgress dialog dismissed");
}
}
}
NewsItems类
public class NewsItems {
private String news_title;
private String news_excerpt;
private int news_id;
public String getNews_title() {
return news_title;
}
public void setNews_title(String news_title) {
this.news_title = news_title;
}
public String getNews_excerpt() {
return news_excerpt;
}
public void setNews_excerpt(String news_excerpt) {
this.news_excerpt = news_excerpt;
}
public int getNews_id() {
return news_id;
}
public void setNews_id(int news_id) {
this.news_id = news_id;
}
}
NewsAdapter
public class NewsAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{
private ImageLoader imageLoader;
private Context mContext;
//List of newss
private List<NewsItems> mNewsItems;
private final int VIEW_ITEM = 0;
private final int VIEW_PROG = 1;
private int lastPosition = -1;
public NewsAdapter(List<NewsItems> newsItems, Context context) {
super();
//Getting all newss
this.mNewsItems = newsItems;
this.mContext = context;
}
@Override
public int getItemViewType(int position) {
if (isPositionItem(position))
return VIEW_ITEM;
return VIEW_PROG;
}
private boolean isPositionItem(int position) {
return position != getItemCount()-1;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder (ViewGroup parent, int viewType) {
if (viewType == VIEW_ITEM) {
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.news_summ, parent, false);
return new TextViewHolder(v, mContext);
} else if (viewType == VIEW_PROG){
View v = LayoutInflater.from(parent.getContext())
.inflate(R.layout.recyclerfooter, parent, false);
return new ProgressViewHolder(v);
}
return null;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof TextViewHolder) {
NewsItems newsList = mNewsItems.get(position);
((TextViewHolder) holder).newsTitle.setText(newsList.getNews_title());
((TextViewHolder) holder).newsExcerpt.setText(newsList.getNews_excerpt());
((TextViewHolder) holder).newsId.setText(String.valueOf(newsList.getNewsId()));
} else {
((ProgressViewHolder) holder).progressBar.setIndeterminate(true);
((ProgressViewHolder) holder).loadButton.setText(R.string.reload);
}
}
@Override
public int getItemCount(){
//Return the number of items in the data set
return mNewsItems.size();
}
public static class TextViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public TextView newsTitle,newsExcerpt, newsId;
public ImageButton imageButton;
public NewsItems dNewsItems;
private Context context;
public TextViewHolder (final View newsView, final Context context) {
super(newsView);
this.context = context;
newsTitle = (TextView) newsView.findViewById(R.id.news_title);
newsExcerpt = (TextView) newsView.findViewById(R.id.news_excerpt);
newsId = (TextView) newsView.findViewById(R.id.news_id);
newsExcerpt.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == newsExcerpt.getId()) {
Intent intent = new Intent(context, NewsDetails.class);
Bundle bundle = new Bundle();
bundle.putSerializable("PostId", //This is where I got confused);
}
}
}
}
public static class ProgressViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
Button loadButton;
ProgressBar progressBar;
public ProgressViewHolder(View footerView){
super(footerView);
loadButton = (Button) footerView.findViewById(R.id.reload_button);
progressBar = (ProgressBar) footerView.findViewById(R.id.progress_load);
loadButton.setOnClickListener(this);
if(NetworkCheck.isAvailableAndConnected(footerView.getContext())) {
progressBar.setVisibility(View.VISIBLE);
} else if (!NetworkCheck.isAvailableAndConnected(footerView.getContext())) {
loadButton.setVisibility(View.VISIBLE);
}
}
@Override
public void onClick(View v) {
if (v.getId() == loadButton.getId()) {
//
}
}
}
}
答案 0 :(得分：1)
您也可以发送单个值而不是像这样的完整对象 -
@Override
public void onClick(View v) {
if (v.getId() == newsExcerpt.getId()) {
Intent intent = new Intent(context, NewsDetails.class);
intent.putExtra("PostId",<your_news_id_here>);
startActivity(intent);
}
}
}
在您的情况下，请删除onClick(View v)并将onBindViewHolder()更改为setOnClickListener() newsExcerpt，如下所示 -
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof TextViewHolder) {
NewsItems newsList = mNewsItems.get(position);
((TextViewHolder) holder).newsTitle.setText(newsList.getNews_title());
((TextViewHolder) holder).newsExcerpt.setText(newsList.getNews_excerpt());
((TextViewHolder) holder).newsId.setText(String.valueOf(newsList.getNewsId()));
((TextViewHolder) holder).newsExcerpt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(context, NewsDetails.class);
intent.putExtra("PostId",newsList.getNewsId()); //Any getter of your class you want
startActivity(intent);
});
} else {
((ProgressViewHolder) holder).progressBar.setIndeterminate(true);
((ProgressViewHolder) holder).loadButton.setText(R.string.reload);
}
}