现在我想使用 ArrayAdapter 将列表视图的特定数据表单显示到另一个列表视图中

Posted 2023-04-19

【中文标题】现在我想使用 ArrayAdapter 将列表视图的特定数据表单显示到另一个列表视图中

【英文标题】：Now i want to display the specific data form that listview into another listview using the ArrayAdapter

【发布时间】：2019-02-14 01:44:10

【问题描述】：

String url = "http://example.com/bilal/fetchparty.php";
StringRequest sr = new StringRequest(1, url, new Response.Listener<String>() 
    @Override
    public void onResponse(String response) 
        try 
            JSONObject jo = new JSONObject(response);
            JSONArray ja = jo.getJSONArray("data");
            cid = new String[ja.length()];
            cname = new String[ja.length()];
            username = new String[ja.length()];
            name1 = new String[ja.length()];                 //for size
            timetaken = new String[ja.length()];
            link = new String[ja.length()];
            ArrayList<HashMap<String, String>> arrayList = new ArrayList<>();
            for (int i = 0; i < ja.length(); i++) 
                JSONObject job = ja.getJSONObject(i);
                cid[i] = job.getString("cid");
                cname[i] = job.getString("cname");
                username[i] = job.getString("username");
                timetaken[i] = job.getString("timetaken");
                link[i] = job.getString("link");

                if (cid[i].equals(shared1.sp1.getString("pid", null)) && cname[i].equals(shared1.sp1.getString("title", null))) 

                    HashMap<String, String> hashMap = new HashMap<>();
                    hashMap.put("cid", cid[i]);
                    hashMap.put("cname", cname[i]);
                    hashMap.put("username", username[i]);
                    hashMap.put("timetaken", timetaken[i]);
                    hashMap.put("link", link[i]);
                    arrayList.add(hashMap);



                    Toast.makeText(Vote.this, username[i], Toast.LENGTH_SHORT).show();
                    nameCall (username);

                

            

            String[] from = "username", "timetaken", "link";
            int[] to = R.id.tvUsername, R.id.tvTime, R.id.tvLink;
            SimpleAdapter sa = new SimpleAdapter(Vote.this, arrayList, R.layout.vote, from, to);
            lvVote.setAdapter(sa);


         catch (JSONException e) 
            e.printStackTrace();
        
    
, new Response.ErrorListener() 
    @Override
    public void onErrorResponse(VolleyError error) 

    
);

RequestQueue requestQueue = Volley.newRequestQueue(Vote.this);
requestQueue.add(sr);

lvVote.setOnItemClickListener(new AdapterView.OnItemClickListener() 
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) 
        bi = link[position];
        Toast.makeText(Vote.this, bi, Toast.LENGTH_SHORT).show();
    
);









private void nameCall(final String name[]) 

    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_single_choice, name);
    lvVoteNow.setAdapter(adapter);
    bVoteSubmit.setOnClickListener(new View.OnClickListener() 
        @Override
        public void onClick(View v) 
            int p;
            String s;
            p = lvVoteNow.getCheckedItemPosition();
            if (p != ListView.INVALID_POSITION) 
                s = name[p];
                Toast.makeText(Vote.this, "You voted for " + s, Toast.LENGTH_SHORT).show();
                //use s here
                s = null;
             else 
                Toast.makeText(Vote.this, "Please Give Your Vote", Toast.LENGTH_SHORT).show();
            

        
    );
 

我从在线服务器获取数据并使用 simpleAdapter 将数据显示到 ListView 中。现在我想使用 ArrayAdapter 将 Listview 的特定数据表单显示到另一个 Listview 中 但它不根据第二个 ListView 中的 if 条件显示整个列表，即 lvVoteNow

【参考方案1】：

这是我的代码

public class Vote extends AppCompatActivity 
    ListView lvVote,lvVoteNow;
    TextView tvUsername,tvTime,tvLink,cidVote,cnameVote;
    List<String> testUserName = new ArrayList<>();

    Button bVoteSubmit;
    String bi;
    String [] cid,cname,username,timetaken,link,name1,name2;

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

        lvVoteNow = findViewById(R.id.lvVoteNow);
        bVoteSubmit = findViewById(R.id.bVoteSubmit);

        tvUsername = findViewById(R.id.tvUsername);
        tvTime = findViewById(R.id.tvTime);
        tvLink = findViewById(R.id.tvLink);
        cidVote = findViewById(R.id.cidVote);
        cnameVote = findViewById(R.id.cnameVote);

        lvVote = findViewById(R.id.lvVote);
        lvVote.setChoiceMode(ListView.CHOICE_MODE_SINGLE);

        final Shared shared1 = new Shared(getApplicationContext());
        cidVote.setText(shared1.sp1.getString("pid", null));
        cnameVote.setText(shared1.sp1.getString("title", null));

        //fetching data for vote

        String url = "http://example.com/bilal/fetchparty.php";
        StringRequest sr = new StringRequest(1, url, new Response.Listener<String>() 
            @Override
            public void onResponse(String response) 
                try 
                    JSONObject jo = new JSONObject(response);
                    JSONArray ja = jo.getJSONArray("data");
                    cid = new String[ja.length()];
                    cname = new String[ja.length()];
                    username = new String[ja.length()];
                    name1 = new String[ja.length()];                 //for size
                    timetaken = new String[ja.length()];
                    link = new String[ja.length()];
                    ArrayList<HashMap<String, String>> arrayList = new ArrayList<>();
                    for (int i = 0; i < ja.length(); i++) 
                        JSONObject job = ja.getJSONObject(i);
                        cid[i] = job.getString("cid");
                        cname[i] = job.getString("cname");
                        username[i] = job.getString("username");
                        timetaken[i] = job.getString("timetaken");
                        link[i] = job.getString("link");

                        if (cid[i].equals(shared1.sp1.getString("pid", null)) && cname[i].equals(shared1.sp1.getString("title", null))) 

                            HashMap<String, String> hashMap = new HashMap<>();
                            hashMap.put("cid", cid[i]);
                            hashMap.put("cname", cname[i]);
                            hashMap.put("username", username[i]);
                            hashMap.put("timetaken", timetaken[i]);
                            hashMap.put("link", link[i]);
                            arrayList.add(hashMap);

                            Toast.makeText(Vote.this, username[i], Toast.LENGTH_SHORT).show();
                            testUserName.add(username[i]); // add userName to list
                           // nameCall (username);
                        
                    
                    //after all specific users add on list to this
                    String[] stringArray = testUserName.toArray(new String[0]);
                    nameCall(stringArray);

                    String[] from = "username", "timetaken", "link";
                    int[] to = R.id.tvUsername, R.id.tvTime, R.id.tvLink;
                    SimpleAdapter sa = new SimpleAdapter(Vote.this, arrayList, R.layout.vote, from, to);
                    lvVote.setAdapter(sa);
                 catch (JSONException e) 
                    e.printStackTrace();
                
            
        , new Response.ErrorListener() 
            @Override
            public void onErrorResponse(VolleyError error) 

            
        );

        RequestQueue requestQueue = Volley.newRequestQueue(Vote.this);
        requestQueue.add(sr);

        lvVote.setOnItemClickListener(new AdapterView.OnItemClickListener() 
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) 
                bi = link[position];
                Toast.makeText(Vote.this, bi, Toast.LENGTH_SHORT).show();
            
        );
    

    private void nameCall(final String name[]) 

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_single_choice, name);
        lvVoteNow.setAdapter(adapter);
        bVoteSubmit.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                int p;
                String s;
                p = lvVoteNow.getCheckedItemPosition();
                if (p != ListView.INVALID_POSITION) 
                    s = name[p];
                    Toast.makeText(Vote.this, "You voted for " + s, Toast.LENGTH_SHORT).show();
                    //use s here
                    s = null;
                 else 
                    Toast.makeText(Vote.this, "Please Give Your Vote", Toast.LENGTH_SHORT).show();
                
            
        );
    

【讨论】：

在 testUserName(username[i]) 中显示错误；说方法调用预期