java - 在按钮单击事件上从表格布局获取值时出错

Question

在我的应用程序中，我从服务器获取值并以表格布局的形式显示它。我不在任何地方储存值(value)。每行的开头都有一个按钮，当用户按下该按钮时，第一列和第一行的值应插入到变量中。我想将名为“product_code”的字段的值存储到变量中。

抱歉我的英语不好。这是我的代码

public class FancyStock extends Activity implements View.OnClickListener {

    String data = "";
    TableLayout tl;
    TableRow tr;
    TextView label;
    Button btn;
    ArrayList<Users_fancystock> users = new ArrayList<Users_fancystock>();



    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fancystock);

        tl = (TableLayout) findViewById(R.id.main_table);

        final GetDatafromDB_fancystock getdb = new GetDatafromDB_fancystock();
        new Thread(new Runnable() {
            public void run() {
                data = getdb.getDataFromDB();
                System.out.println(data);

                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        ArrayList<Users_fancystock> users = parseJSON(data);
                        addData(users);
                    }
                });

            }
        }).start();



    }

    public ArrayList<Users_fancystock> parseJSON(String result) {
        ArrayList<Users_fancystock> users = new ArrayList<Users_fancystock>();
        try {
            JSONArray jArray = new JSONArray(result);
            for (int i = 0; i < jArray.length(); i++) {
                JSONObject json_data = jArray.getJSONObject(i);
                Users_fancystock user = new Users_fancystock();
                user.setId(json_data.getInt("id"));
                user.setProduct_code(json_data.getString("product_code"));
                user.setShapes(json_data.getString("shaps"));
                user.setPair(json_data.getString("pair"));
                user.setCarats(json_data.getString("carats"));
                user.setColor(json_data.getString("color"));
                user.setClarity(json_data.getString("clarity"));
                user.setService(json_data.getString("service"));
                user.setPolish(json_data.getString("polish"));
                user.setSymetric(json_data.getString("symetric"));
                user.setTables(json_data.getString("tables"));
                user.setMeasurements(json_data.getString("measurments"));
                user.setFlourscne(json_data.getString("flourscne"));
                user.setDescription(json_data.getString("description"));
                user.setCerticated(json_data.getString("certificated"));
                user.setCcode(json_data.getString("ccode"));
                user.setCut(json_data.getString("cut"));
                user.setTotal(json_data.getString("total"));
                user.setFile(json_data.getString("file"));
                users.add(user);
            }
        } catch (JSONException e) {
            Log.e("log_tag", "Error parsing data " + e.toString());
        }
        return users;
    }



    void addHeader(){
        /** Create a TableRow dynamically **/
        tr = new TableRow(this);

        TextView add = new TextView(this);
        add.setText("Add");
        add.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT));
        add.setPadding(5, 5, 5, 5);
        add.setBackgroundColor(Color.parseColor("#BDB76B"));
        LinearLayout Ll = new LinearLayout(this);
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                LayoutParams.WRAP_CONTENT);
        params.setMargins(0, 5, 5, 5);
        //Ll.setPadding(10, 5, 5, 5);
        Ll.addView(add,params);
        tr.addView((View)Ll);

        /** Creating a TextView to add to the row **/
        label = new TextView(this);
        label.setText("Product code");

        label.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT));
        label.setPadding(5, 5, 5, 5);
        label.setBackgroundColor(Color.parseColor("#BDB76B"));
        Ll = new LinearLayout(this);
        params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                LayoutParams.WRAP_CONTENT);
        params.setMargins(5, 5, 5, 5);
        //Ll.setPadding(10, 5, 5, 5);
        Ll.addView(label,params);
        tr.addView((View)Ll);  // Adding textView to tablerow.

        /** Creating Qty Button **/
        TextView shapes = new TextView(this);
        shapes.setText("Shapes");
        shapes.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT));
        shapes.setPadding(5, 5, 5, 5);
        shapes.setBackgroundColor(Color.parseColor("#BDB76B"));
        Ll = new LinearLayout(this);
        params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT);
        params.setMargins(0, 5, 5, 5);
        //Ll.setPadding(10, 5, 5, 5);
        Ll.addView(shapes,params);
        tr.addView((View)Ll); // Adding textview to tablerow.

        TextView pair = new TextView(this);
        pair.setText("Shapes");
        pair.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
        pair.setPadding(5, 5, 5, 5);
        pair.setBackgroundColor(Color.parseColor("#BDB76B"));
        Ll = new LinearLayout(this);
        params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT);
        params.setMargins(0, 5, 5, 5);
        //Ll.setPadding(10, 5, 5, 5);
        Ll.addView(pair,params);
        tr.addView((View)Ll); // Adding textview to tablerow.




        // Add the TableRow to the TableLayout
        tl.addView(tr, new TableLayout.LayoutParams( LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
    }

    @SuppressWarnings({ "rawtypes" })
    public void addData(ArrayList<Users_fancystock> users) {

        addHeader();

        for (Iterator i = users.iterator(); i.hasNext();) {
            for (int j = 0; j < users.size(); j++) {

                Users_fancystock p = (Users_fancystock) i.next();

                /** Create a TableRow dynamically **/
                tr = new TableRow(this);

///-----------------------buttpm here-------------------------------------------------------
                Button btn = new Button(this);
                btn.setTag(j);
                System.out.println(btn.getTag());

                btn.setText("Add to Basket");
                // btn.setTextSize();
                btn.setTextSize(TypedValue.COMPLEX_UNIT_SP, 12);
                // btn.setTag(mLinks.get(index));
                btn.setOnClickListener(this);
                LinearLayout Ll = new LinearLayout(this);
                LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                        LayoutParams.WRAP_CONTENT);
                params.setMargins(5, 2, 2, 2);
                params.width = 200;
                params.height = 60;
                // btn.setLayoutParams(new LinearLayout.LayoutParams(10, 100));
                Ll.addView(btn, params);

                tr.addView((View) Ll);


                /** Creating a TextView to add to the row **/
                label = new TextView(this);
                label.setText(p.getproduct_code());
                label.setId(p.getId());
                label.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                        LayoutParams.WRAP_CONTENT));
                label.setPadding(5, 5, 5, 5);
                ////label.setBackgroundColor(Color.parseColor("#BDB76B"));
                Ll = new LinearLayout(this);
                params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                        LayoutParams.WRAP_CONTENT);
                params.setMargins(5, 2, 2, 2);
                //Ll.setPadding(10, 5, 5, 5);
                Ll.addView(label, params);
                tr.addView((View) Ll); // Adding textView to tablerow.

                /** Creating Qty Button **/
                TextView place = new TextView(this);
                place.setText(p.getShapes());
                place.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                        LayoutParams.WRAP_CONTENT));
                place.setPadding(5, 5, 5, 5);
                //  place.setBackgroundColor(Color.parseColor("#BDB76B"));
                Ll = new LinearLayout(this);
                params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                        LayoutParams.WRAP_CONTENT);
                params.setMargins(0, 2, 2, 2);
                //Ll.setPadding(10, 5, 5, 5);
                Ll.addView(place, params);
                tr.addView((View) Ll); // Adding textview to tablerow.

                label = new TextView(this);
                label.setText(p.getpair());
                label.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,
                        LayoutParams.WRAP_CONTENT));
                label.setPadding(5, 5, 5, 5);
                ////label.setBackgroundColor(Color.parseColor("#BDB76B"));
                Ll = new LinearLayout(this);
                params = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                        LayoutParams.WRAP_CONTENT);
                params.setMargins(5, 2, 2, 2);
                //Ll.setPadding(10, 5, 5, 5);
                Ll.addView(label, params);
                tr.addView((View) Ll); // Adding textView to tablerow.



                // Add the TableRow to the TableLayout
                tl.addView(tr, new TableLayout.LayoutParams(
                        LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
            }
        }
    }
    public void onClick(View v)
    {
       int k=(Integer)btn.getTag();
        Users_fancystock rowRecord= users.get(k);
        System.out.println(rowRecord);

    }
}

这是我的错误

07-07 09:12:45.950  13184-13184/com.diamond.traders D/AndroidRuntime﹕ Shutting down VM
07-07 09:12:45.950  13184-13184/com.diamond.traders W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x415dcba8)
07-07 09:12:45.950  13184-13184/com.diamond.traders E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.diamond.traders, PID: 13184
    java.lang.NullPointerException
            at com.diamond.traders.FancyStock.onClick(FancyStock.java:669)
            at android.view.View.performClick(View.java:4438)
            at android.view.View$PerformClick.run(View.java:18422)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5001)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
            at dalvik.system.NativeStart.main(Native Method)

新错误

07-07 09:36:53.845  15932-15932/com.diamond.traders E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.diamond.traders, PID: 15932
    java.lang.IndexOutOfBoundsException: Invalid index 1, size is 0
            at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
            at java.util.ArrayList.get(ArrayList.java:308)
            at com.diamond.traders.FancyStock.onClick(FancyStock.java:670)
            at android.view.View.performClick(View.java:4438)
            at android.view.View$PerformClick.run(View.java:18422)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5001)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
            at dalvik.system.NativeStart.main(Native Method)

Answer 1

您尚未分配btn 字段。

由于(我认为)您想要单击按钮的标签，因此只需使用 v.getTag() 即可(提供的 v 是单击的 View )。

更改此:

int k = (Integer)btn.getTag();

进入此:

int k = (Integer)v.getTag();

我还建议在类(class)开始时删除 Button btn;。

至少还有一个问题:

runOnUiThread(new Runnable() {
   @Override
   public void run() {
       ArrayList<Users_fancystock> users = parseJSON(data);
       addData(users);
   }
});

您没有更新文件顶部定义的users 字段。这个可运行程序应该是:

   public void run() {
       users = parseJSON(data);
       addData(users);
   }