Java 如何从类中获取字符串

我正在使用《纽约时报》电影评论API制作一个电影评论应用程序，该API给了我一个字符串“short_summary”，我有一个类将API中的所有信息转换为ListView，我想创建一个新的活动，向用户显示评论的摘要，但我知道如何获取这些信息的唯一方法就是做与MovieArrayAdapter相同的事情

有没有一种方法可以让我只从用户点击列表的评论中获得简短的摘要

MainActivity.java

package br.com.pedro.pedrodaumas;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.design.widget.TextInputEditText;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.view.inputmethod.InputMethodManager;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListView;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private List<Movie> movieList = new ArrayList<>();
    private MovieArrayAdapter movieArrayAdapter;
    private ListView movieListView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        movieListView = (ListView) findViewById(R.id.movieListView);
        movieArrayAdapter = new MovieArrayAdapter(this, movieList);
        movieListView.setAdapter(movieArrayAdapter);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                TextInputEditText search_bar;
                search_bar = (TextInputEditText) findViewById(R.id.search_bar);
                URL url = createURL(search_bar.getText().toString());
                if(url != null){
                    dismissKeyboard(search_bar);
                    GetMovieTask getLocalMovieTask = new GetMovieTask();
                    getLocalMovieTask.execute(url);
                }else {
                    Snackbar.make(findViewById(R.id.coordinatorLayout), R.string.invalid_url,
                            Snackbar.LENGTH_LONG).show();
                }

            }
        });
        movieListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                switch (position) {
                    default:
                        Intent nextActivity = new Intent(MainActivity.this, ShortReview.class);
                        startActivity(nextActivity);
                        break;
                }
            }
        });
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    private void dismissKeyboard (View view){
        InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(view.getWindowToken(),0);
    }

    private URL createURL (String movie){
        String apiKey = getString (R.string.api_key);
        String baseUrl = getString(R.string.nyt_url);
        try{
            String urlString = baseUrl + "?api_key=" + apiKey + "&query=" + URLEncoder.encode (movie, "UTF-8");
            return new URL(urlString);
        }
        catch( Exception e){
            e.printStackTrace();
        }
        return null;
    }

    private class GetMovieTask extends AsyncTask<URL, Void, JSONObject> {
        @TargetApi(Build.VERSION_CODES.KITKAT)
        @Override
        protected JSONObject doInBackground(URL... params) {
            HttpURLConnection connection = null;
            try {
                connection = (HttpURLConnection) params[0].openConnection();
                int response = connection.getResponseCode();
                if (response == HttpURLConnection.HTTP_OK){
                    StringBuilder builder = new StringBuilder ();
                    try (BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()))){
                        String line;
                        while ((line = reader.readLine()) != null){
                            builder.append(line);
                        }
                    }
                    catch (IOException e){
                        Snackbar.make(findViewById(R.id.coordinatorLayout), R.string.read_error, Snackbar.LENGTH_LONG).show();
                        e.printStackTrace();
                    }
                    return new JSONObject(builder.toString());
                }
            }
            catch (Exception e){
                Snackbar.make(findViewById(R.id.coordinatorLayout), R.string.connect_error, Snackbar.LENGTH_LONG).show();
                e.printStackTrace();
            }
            finally{
                if (connection != null){
                    connection.disconnect();
                }
            }
            return null;
        }
        protected void onPostExecute(JSONObject movie) {
            convertJSONToArrayList (movie);
            movieArrayAdapter.notifyDataSetChanged();
            movieListView.smoothScrollToPosition(0);
        }
    }

    private void convertJSONToArrayList (JSONObject forecast){
        movieList.clear();
        try{
            JSONArray results = forecast.getJSONArray("results");
            for (int i = 0; i < results.length(); i++) {
                JSONObject movie = results.getJSONObject(i);
                if(movie.isNull("multimedia")){
                    movieList.add(new Movie(movie.getString("display_title"),
                            movie.getString("publication_date"),
                            "image", movie.getString("summary_short")));
                }else {
                    JSONObject multimedia = movie.getJSONObject("multimedia");
                    movieList.add(new Movie(movie.getString("display_title"),
                            movie.getString("publication_date"),
                            multimedia.getString("src"), movie.getString("summary_short")));
                }
            }
        }
        catch (JSONException e){
            e.printStackTrace();
        }
    }

}

MovieArrayAdapter.java

package br.com.pedro.pedrodaumas;

import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Build;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MovieArrayAdapter extends ArrayAdapter<Movie> {

    private static class ViewHolder{
        ImageView movieImage;
        TextView description;
        TextView publication_date;
    }

    private Map<String, Bitmap> bitmaps = new HashMap<>();
    public MovieArrayAdapter (Context context, List<Movie>
            forecast){
        super (context, -1, forecast);
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        Movie review = getItem (position);
        ViewHolder viewHolder;
        if (convertView == null){
            viewHolder = new ViewHolder();
            LayoutInflater inflater = LayoutInflater.from(getContext());
            convertView = inflater.inflate(R.layout.complete_review, parent, false);
            viewHolder.movieImage = (ImageView)convertView.findViewById(R.id.movieImage);
            viewHolder.description = (TextView)convertView.findViewById(R.id.description);
            viewHolder.publication_date = (TextView)convertView.findViewById(R.id.publication_date);
            convertView.setTag(viewHolder);
        }
        else{
            viewHolder = (ViewHolder)convertView.getTag();
        }
        if(review.iconURL == "image"){
            viewHolder.movieImage.setImageResource(R.drawable.ic_import_contacts_white_24dp);
        }
        else{
            new LoadImageTask (viewHolder.movieImage).execute (review.iconURL);
        }

        Context context = getContext();
        viewHolder.description.setText(review.title);
        viewHolder.publication_date.setText(review.publication_date);
        return convertView;
    }

    private class LoadImageTask extends AsyncTask<String, Void, Bitmap> {
        private ImageView imageView;
        public LoadImageTask (ImageView imageView){
            this.imageView = imageView;
        }
        @TargetApi(Build.VERSION_CODES.KITKAT)
        @Override
        protected Bitmap doInBackground(String... params) {
            Bitmap bitmap = null;
            HttpURLConnection connection = null;
            try{
                URL url = new URL(params[0]);
                connection = (HttpURLConnection) url.openConnection();
                try(InputStream inputStream = connection.getInputStream ()){
                    bitmap = BitmapFactory.decodeStream(inputStream);
                    bitmaps.put (params[0], bitmap);
                }
                catch (Exception e){
                    e.printStackTrace();
                }
            }
            catch (Exception e){
                e.printStackTrace();
            }
            finally{
                connection.disconnect();
            }
            return bitmap;
        }
        protected void onPostExecute(Bitmap bitmap) {
            imageView.setImageBitmap(bitmap);
        }
    }
}

---

你可以使用intent-extra

Intent intent = new Intent(FirstActivity.this,SecondActivity.class);
intent.putExtra("short_summary", "the summary is here");
startActivity(intent)

然后获取第二个活动的字符串值

Bundle bundle = getIntent().getExtras();
    if (bundle!=null){
        String summary = bundle.getString("short_summary");
       }

---

感谢（） 通过使用getSummary并将其添加到putExtra，我可以解决我的问题

以下是我所改变的：

维护性

简短回顾

---

遗憾的是，它不起作用，或者我太笨了，无法使用它（可能是这样），我需要从函数convertJSONToArrayList上的NYT API获取字符串“short_summary”。

Intent intent = new Intent(FirstActivity.this,SecondActivity.class);
intent.putExtra("short_summary", "the summary is here");
startActivity(intent)

Bundle bundle = getIntent().getExtras();
    if (bundle!=null){
        String summary = bundle.getString("short_summary");
       }

        @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        switch (position) {
            default:
                Movie review = movieArrayAdapter.getItem(position);
                Intent nextActivity = new Intent(MainActivity.this, ShortReview.class);
                nextActivity.putExtra("summary", review.getsummary());
                startActivity(nextActivity);
                break;
        }
    }
});

public String getsummary() {
    return short_summary;
}

private TextView short_summary;
private String s_summary;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.movie_description);

    Intent intent = getIntent();
    if (null != intent) {
        s_summary = intent.getStringExtra("summary");

    }
    short_summary = (TextView) findViewById(R.id.short_summary);
    short_summary.setText(s_summary);
}