从JSONObject到ListView的Android数据显示格式错误 [英] Android data display in wrong format from JSONObject to ListView
问题描述
我尝试用HashMap和Listview显示2列数据，它工作正常.当我尝试显示多于2列时出现错误.
I try to display 2 column data with HashMap and Listview, it works fine. The error comes when I try to display more than 2 columns.
2_columns.java
public class Main4Activity extends AppCompatActivity {
String url = "http://192.168.1.103/web_service/omg.php/";
private static final String COLUMN_ID = "ID";
private static final String COLUMN_NAME = "Name";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main4);
JsonObjectRequest jsObjRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
List<HashMap<String, String>> aList = new ArrayList<HashMap<String, String>>();
try {
Iterator<String> iterator = response.keys();
while (iterator.hasNext()) {
String key = iterator.next();
String value = response.getString(key);
HashMap<String, String> map = new HashMap<>();
map.put(COLUMN_ID, key);
map.put(COLUMN_NAME, value);
aList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
if(aList.size() > 0) {
String[] from = {COLUMN_ID, COLUMN_NAME};
int[] to = {R.id.text_id, R.id.text_name};
SimpleAdapter adapter = new SimpleAdapter(Main4Activity.this, aList, R.layout.list_item, from, to);
ListView listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(adapter);
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.d("error", "error ");
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(jsObjRequest);
}
}
localhost/web_service/omg.php
{
"32":"Western Food",
"33":"Chinese Food",
"34":"Mix Food",
"35":"Japanese Food",
"36":"Korean Food",
"37":"Italian Food",
"38":"German Food"
}
上面的编码工作正常.但是，当我尝试在多列中显示数据时，就会出现错误，
The above coding is working fine. But the errors come when I try to display data in multiple columns,
multiple_columns.java
String url = "http://192.168.1.103/web_service/ohno.php/";
private static final String product_sku = "SKU";
private static final String product_name = "Name";
private static final String product_price = "Price";
private static final String product_quantity = "Quantity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main5);
JsonObjectRequest jsObjRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
List<HashMap<String, String>> aList = new ArrayList<HashMap<String, String>>();
try {
Iterator<String> iterator = response.keys();
while (iterator.hasNext()) {
String key = iterator.next();
String value_sku = response.getString(key);
String value_name= response.getString(key);
String value_price= response.getString(key);
String value_quantity= response.getString(key);
HashMap<String, String> map = new HashMap<>();
map.put(product_sku, value_sku);
map.put(product_name, value_name);
map.put(product_price, value_price);
map.put(product_quantity, value_quantity);
aList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
if(aList.size() > 0) {
String[] from = {product_sku,product_name, product_price,product_quantity};
int[] to = {R.id.sku,R.id.name, R.id.price,R.id.quantity};
SimpleAdapter adapter = new SimpleAdapter(Main5Activity.this, aList, R.layout.list_item2, from, to);
ListView listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(adapter);
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.d("error", "error ");
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(jsObjRequest);
}
localhost/web_service/ohno.php
{
"482":["1","Chicken Rice","1","1"],
"483":["1","French Fries","1","1"],
"484":["1","apple","1","1"],
"492":["1","western+italian","1","1"],
"493":["1","no_cat","1","1"]
}
从上面的屏幕截图中可以看到，我希望Key为482,483,484 ...，其值在右侧.编码有什么问题?
As you can see from the above screenshot, I want the Key to be 482,483,484... and the value its on the right side. What's wrong with the coding?
推荐答案
似乎JSON中的值是JSONArray，因此response.getString(key)会将整个数组返回为String.
Seems like the values in your JSON are JSONArrays, so response.getString(key) will return the whole array as a String.
调用getJSONArray()以获取JSONArray的值，因此您可以单独处理这些项目.
Call getJSONArray() to get the values as a JSONArray, so you can process the items individually.
类似的事情应该起作用:
Something like this should work:
try {
Iterator<String> iterator = response.keys();
while (iterator.hasNext()) {
String key = iterator.next();
JSONArray array = response.getJSONArray(key);
HashMap<String, String> map = new HashMap<>();
map.put(product_sku, array.getString(0));
map.put(product_name, array.getString(1));
map.put(product_price, array.getString(2));
map.put(product_quantity, array.getString(3));
aList.add(map);
}
} catch (JSONException e) {
e.printStackTrace();
}
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