在我的活动中，我添加了一个标题按钮来保存listview的值，使用EditText并将它们发布到php / mysql Web应用程序。
如果我使用setOnItemClickListener，我可以获取listview的值，但是当我在标题保存按钮上使用setOnClickListener时，我无法遍历listview。
我正在使用自定义数组适配器： -
public class CustomOrderAdaptor extends ArrayAdapter { int groupid;
ArrayList<OneOrder> records;
Context context;
public CustomOrderAdaptor(Context context, int vg, int id, ArrayList<OneOrder>records) {
super(context, vg, id, records);
this.context = context;
groupid = vg;
this.records = records;
}
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View itemView = inflater.inflate(groupid, parent, false);
TextView textName = (TextView) itemView.findViewById(R.id.product_name);
textName.setText(records.get(position).getproduct_name());
EditText new_quantity = (EditText) itemView.findViewById(R.id.new_quantity);
new_quantity.setText(records.get(position).getnew_quantity());
TextView textOrderitemid = (TextView) itemView.findViewById(R.id.order_item_id);
textOrderitemid.setText(records.get(position).getorder_item_id());
TextView textQuantity = (TextView) itemView.findViewById(R.id.quantity);
textQuantity.setText(records.get(position).getquantity());
return itemView;
}
}
数据模型： -
public class OneOrder {
private String quantity;
private String new_quantity;
private String product_name;
private String order_item_id;
public void setquantity(String quantity){this.quantity=quantity;}
public void setnew_quantity(String new_quantity){this.new_quantity=new_quantity;}
public void setproduct_name(String product_name){this.product_name=product_name;}
public void setorder_item_id(String order_item_id){this.order_item_id=order_item_id;}
public String getquantity(){return quantity;}
public String getnew_quantity(){return new_quantity;}
public String getproduct_name(){return product_name;}
public String getorder_item_id(){return order_item_id;}
}
我的活动是： -
protected void onCreate(Bundle savedInstanceState) {
//TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_get_order);
context = this;
records = new ArrayList<OneOrder>();
listOrder = (ListView) findViewById(R.id.order_item_list);
LayoutInflater inflater = LayoutInflater.from(this);
View nTop = inflater.inflate(R.layout.activity_get_order_footer, null);
listOrder.addHeaderView(nTop);
adapter = new CustomOrderAdaptor(context, R.layout.list_order, R.id.product_name,
records);
listOrder.setAdapter(adapter);
Button mButton = (Button) nTop.findViewById(R.id.button_save);
mButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
JSONObject order_items = new JSONObject();
JSONObject sendObject = new JSONObject();
for (int i=0;i<adapter.getCount();i++){
JSONObject order_item = new JSONObject();
OneOrder current_order = (OneOrder) listOrder.getAdapter().getItem(i);
//OneOrder current_order = (OneOrder) getListView().getItemAtPosition(i);
try {
order_item.put("quantity", current_order.getquantity().toString());
order_item.put("new_quantity", current_order.getnew_quantity().toString());
order_item.put("order_item_id", current_order.getorder_item_id().toString());
order_items.put(String.valueOf(i),order_item);
} catch (JSONException e) {
e.printStackTrace();
}
}
HttpURLConnection conn = null;
try {
Intent i = getIntent(); // gets the previously created intent
String order_id = i.getStringExtra("order_id");
sendObject.put("items", order_items.toString());
sendObject.put("order_id", order_id);
try {
URL url = new URL("http://192.168.0.70/steam_dos/index.php?option=com_steam§ion=linen&task=save_order_out");
String message = sendObject.toString();
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout( 10000 /*milliseconds*/ );
conn.setConnectTimeout( 15000 /* milliseconds */ );
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setFixedLengthStreamingMode(message.getBytes().length);
//make some HTTP header nicety
conn.setRequestProperty("Content-Type", "application/json;charset=utf-8");
conn.setRequestProperty("X-Requested-With", "XMLHttpRequest");
//open
conn.connect();
//setup send
BufferedOutputStream os = new BufferedOutputStream(conn.getOutputStream());
os.write(message.getBytes());
//clean up
os.flush();
//do something with response
InputStream is = conn.getInputStream();
}catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
}
错误在这里： -
order_item.put("quantity", current_order.getquantity().toString());
错误很简单： -
java.lang.NullPointerException：尝试调用虚拟方法＆java; .js。在空对象引用上
视图如下所示： -
我在点击保存按钮后尝试保存listview的所有值但是我没有获得带有该代码的listview项目，请问您能解释实现这一目标的最佳方法吗？感谢。
答案 0 :(得分：0)
通常不建议使用带适配器的编辑文本，原因是滚动时无法处理编辑文本保存。
有两种解决方案。
2创建一个变量并在edittext上添加TextWatcher。每当修改edittext时，文本观察者都会检测到更改并覆盖您在其上执行某些操作的变量。
答案 1 :(得分：0)
我的回答可能不是最好的，但这是我为获取列表视图的EditText值而实现的：
mButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
JSONObject order_item = new JSONObject();
order_items_edited = new JSONObject();
for (int i = 0; i < listOrder.getCount(); i++) {
EditText et = (EditText) listOrder.getChildAt(i).findViewById(R.id.new_quantity);
if (et!=null) {
TextView oi = (TextView) listOrder.getChildAt(i).findViewById(R.id.order_item_id);
Log.i("dtag", "et is " + String.valueOf(et.getText()));
Log.i("dtag", "oi is " + String.valueOf(oi.getText()));
try {
order_item.put("new_quantity", String.valueOf(et.getText()));
order_item.put("order_item_id", String.valueOf(oi.getText()));
order_items_edited.put(String.valueOf(i),order_item);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
我遇到的主要问题是et的null对象，这是有效的，但我没有测试它。
现在它的工作，我将着眼于实施一个更清洁的解决方案。