java访问Arraylist项

Question

我想从onItemClickListener中的bookList访问项目。我想访问特定的书籍并从中获取特定的项目如何做到这一点

代码是：

// Creating volley request obj
final JsonArrayRequest bookrequest = new JsonArrayRequest(url,
        new Response.Listener<JSONArray>() {
            @Override
            public void onResponse(JSONArray response) {
                Log.d(TAG, response.toString());
                hidePDialog();

                // Parsing json
                for (int i = 0; i < response.length(); i++) {
                    try {
                        JSONObject obj =(JSONObject) response.getJSONObject(i);
                        Book book = new Book();
                        book.setTitle(obj.getString("BTitle"));
                        book.setThumbnailUrl(obj.getString("BCoverpath"));
                        book.setAuthor(obj.getString("BAuthor"));
                        book.setEdition(obj.getString("BEdition"));
                        book.setCategory(obj.getString("Bcategory"));
                        book.setLanguage(obj.getString("BLanguage"));
                        book.setDescription(obj.getString("BDescription"));
                        book.setCover(obj.getString("BCover"));
                        book.setOwner(obj.getString("UserFN"));

                        // adding book to books array
                        bookList.add(book);
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }

                // notifying list adapter about data changes
                // so that it renders the list view with updated data
                adapter.notifyDataSetChanged();
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                VolleyLog.d(TAG, "Error: " + error.getMessage());
                hidePDialog();
            }
        }
);

// Adding request to request queue
AppController.getInstance().addToRequestQueue(bookrequest);

// setting an onItem click listener in order to open the view book activity
listView.setOnItemClickListener(new 安卓.widget.AdapterView.OnItemClickListener(){
    @Override
    public void onItemClick(AdapterView<?> arg0, View view, int arg2, long arg3) {
        bookname=((TextView)view.findViewById(R.id.title)).getText().toString();
        Bauthor=((TextView)view.findViewById(R.id.author)).getText().toString();
        Bedition=((TextView)view.findViewById(R.id.edition)).getText().toString();

        // intent to take the viewbook activity as its next dextination
        Intent i = new Intent(getApplicationContext(), ViewBook.class);

        // putting the name of the book with the inten extra package to use it as
        // a key to retrieve the book info from the database and display it
        i.putExtra("bookname",bookname);
        i.putExtra("category",Bcategory);
        i.putExtra("Bauthor",Bauthor);
        i.putExtra("Bedition",Bedition);

        startActivity(i);
    }
});

我尝试了许多方法，其中大多数都以越界异常和索引越界结束

Answer 1

在onItemClick(...)中，您可以访问被单击的项目的位置和项目的来源，以便使用该信息获取被单击的实际项目

我将这些参数重命名为onItemClick()，为它们提供了一个更具描述性的名称，并假设Book中的字段有匹配的getter方法

@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    Book b = bookList.get(position);

    Intent i = new Intent(Romance.this, ViewBook.class)
            .putExtra("bookname", b.getTitle())
            .putExtra("category", b.getCategory())
            .putExtra("Bauthor", b.getAuthor())
            .putExtra("Bedition", b.getEdition);

    startActivity(i);
}