Question

这里我显示1个listview来自server.if我点击任何项目我想要一些警告框打开...但为此我需要匹配条件eg.if listitem字符串匹配＆＃34; Bianca比萨饼＆＃34;然后打开alertbox其他吐司＆＃34;你好＆＃34; ..在我的代码中这里没有采取listview项目字符串。

奇怪的是它在toast中获取listview项的第一个值（我之前提出的代码，如果条件只是为了检查它是否正确。）但是当我比较它不工作时。

像吐司一样，我得到了＃Bianca pizza＆＃34;但是当我想将它与Bianca Pizza＆＃34;它应匹配并进入if条件但它不会进入并显示其他条件。

这是我的代码：

    public class SubMenu extends AppCompatActivity {

    JSONObject jsonobject;
    JSONArray jsonarray;
    ListView listview;
    ListViewAdapter adapter;
    ProgressDialog mProgressDialog;
    ArrayList<HashMap<String, String>> arraylist;
    static String RANK = "id";
    static String COUNTRY = "name";
    private ProgressDialog pDialog;
    String status="";
    static String FLAG = "image";
    Integer i = 1;
    String _stringVal;





    private static String url_create_book = "http://cloud....com/broccoli/creatinfo.php";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);


        setContentView(R.layout.activity_sub_menu);

        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        String SelectedId = getIntent().getStringExtra("id");


        getSupportActionBar().setDisplayHomeAsUpEnabled(true);


        // Get the view from listview_main.xml

        // Execute DownloadJSON AsyncTask
        new DownloadJSON().execute();
    }

    // DownloadJSON AsyncTask
    private class DownloadJSON extends AsyncTask<Void, Void, Void> implements AdapterView.OnItemClickListener, AdapterView.OnItemSelectedListener {

        // @Override
        //  protected void onPreExecute() {
        //  super.onPreExecute();
        // Create a progressdialog
        //   mProgressDialog = new ProgressDialog(SubMenu.this);
        // Set progressdialog title
        //   mProgressDialog.setTitle("Categories of Main categories.....");
        // Set progressdialog message
        //  mProgressDialog.setMessage("Loading...");
        //  mProgressDialog.setIndeterminate(false);
        // Show progressdialog
        //  mProgressDialog.show();
        // }

        @Override
        protected Void doInBackground(Void... params) {
            // Create an array
            arraylist = new ArrayList<HashMap<String, String>>();
            // Retrieve JSON Objects from the given URL address
            jsonarray = JsonFunctions
                    .getJSONfromURL("http://cloud....com/broccoli/menu_typeitem.php?id=" + getIntent().getStringExtra("id"));
            try {
                for (int i = 0; i < jsonarray.length(); i++) {
                    HashMap<String, String> map = new HashMap<String, String>();
                    jsonobject = jsonarray.getJSONObject(i);
                    map.put("name", jsonobject.getString("name"));
                    map.put("image", jsonobject.getString("image"));
                    // Set the JSON Objects into the array
                    arraylist.add(map);
                }
            } catch (JSONException e) {
                Log.e("Error", e.getMessage());
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void args) {
            // Locate the listview in listview_main.xml
            listview = (ListView) findViewById(R.id.list1);
            // Pass the results into ListViewAdapter.java
            adapter = new ListViewAdapter(SubMenu.this, arraylist);
            // Set the adapter to the ListView
            listview.setAdapter(adapter);
            listview.setOnItemClickListener(this);

        }


        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long rowId) {

            TextView name = (TextView) parent.findViewById(R.id.type1);


            Toast.makeText(SubMenu.this, "this is "+name.getText(), Toast.LENGTH_SHORT).show();



            if ( name.getText().toString().equalsIgnoreCase("Bian‌‌ca Pizza"))
            {
           //open alertbox
            }
             else{

                Toast.makeText(SubMenu.this, "hello", Toast.LENGTH_SHORT).show();
}

这是我的listview适配器：

public class ListViewAdapter extends BaseAdapter {

    // Declare Variables
    Context context;
    LayoutInflater inflater;
    ArrayList<HashMap<String, String>> data;
    ImageLoader imageLoader;
    HashMap<String, String> resultp = new HashMap<String, String>();

    public ListViewAdapter(Context context,
                           ArrayList<HashMap<String, String>> arraylist) {
        this.context = context;
        data = arraylist;
        imageLoader = new ImageLoader(context);
    }

    @Override
    public int getCount() {
        return data.size();
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    public View getView(final int position, View convertView, ViewGroup parent) {
        // Declare Variables
        TextView id;
        TextView name;
        TextView population;
        CircleImageView image;

        inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        View itemView = inflater.inflate(R.layout.list_item1, parent, false);
        // Get the position
        resultp = data.get(position);

        // Locate the TextViews in listview_item.xml
       // id = (TextView) itemView.findViewById(R.id.idq);
        name = (TextView) itemView.findViewById(R.id.type1);


        // Locate the ImageView in listview_item.xml
        image = (CircleImageView) itemView.findViewById(R.id.subimg);
      //  icon = (ImageView) itemView.findViewById(R.id.arrow);
        // Capture position and set results to the TextViews
      //  id.setText(resultp.get(SubMenu.RANK));
        name.setText(resultp.get(SubMenu.COUNTRY));

        // Capture position and set results to the ImageView
        // Passes flag images URL into ImageLoader.class
        imageLoader.DisplayImage(resultp.get(SubMenu.FLAG), image);
      //  imageLoader.DisplayImage(resultp.get(SubMenu.FLAG), icon);
        // Capture ListView item click
        /**itemView.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
        // Get the position
        resultp = data.get(position);
        Intent intent = new Intent(context, SingleItemView.class);
        // Pass all data rank
        intent.putExtra("rank", resultp.get(MainActivity.RANK));
        // Pass all data country
        intent.putExtra("country", resultp.get(MainActivity.COUNTRY));
        // Pass all data population
        intent.putExtra("population",resultp.get(MainActivity.POPULATION));
        // Pass all data flag
        intent.putExtra("flag", resultp.get(MainActivity.FLAG));
        // Start SingleItemView Class
        context.startActivity(intent);

        }
        });*/
        return itemView;
    }
}

Answer 1

问题是您使用了parent！ parent是整个适配器视图，它包含许多行，其中有Textview，其id为“R.id.type1”。当您使用父级时，它会在其层次结构中找到具有该ID的第一个项目。这就是它总是返回第一项的原因。

你应该这样做：

 @Override
    public void onItemClick(AdapterView<?> parent, View view,
                            int position, long rowId) {

        // TextView name = (TextView) parent.findViewById(R.id.type1); WRONG
        TextView name = (TextView) view.findViewById(R.id.type1);
        Toast.makeText(SubMenu.this, "this is "+name.getText(), Toast.LENGTH_SHORT).show();
        if ( name.getText().toString().equalsIgnoreCase("Bian‌‌ca Pizza"))
        {
       //open alertbox
        }
        else {
          Toast.makeText(SubMenu.this, "hello", Toast.LENGTH_SHORT).show();
        }
    }

Answer 2

您需要做的唯一更改是在onItemClick上使用view而不是parent，请参阅下面的内容 - 这将直接获取点击的项目文本。

    @Override
    public void onItemClick(AdapterView<?> parent, View view,
                            int position, long rowId) {

        TextView name = (TextView) view.findViewById(R.id.type1);


        Toast.makeText(SubMenu.this, "this is "+name.getText(), Toast.LENGTH_SHORT).show();



        if ( name.getText().toString().equals("Bian‌‌ca Pizza"))
        {
       //open alertbox
        }
         else{
            Toast.makeText(SubMenu.this, "hello", Toast.LENGTH_SHORT).show();
    }

Answer 3

我认为这对您有帮助。

首先在项目点击之前关闭DownloadJSON类，然后调用onitem点击功能。

 private class DownloadJSON extends AsyncTask<Void, Void, Void> implements    
 AdapterView.OnItemClickListener, AdapterView.OnItemSelectedListener {

    // @Override
    //  protected void onPreExecute() {
    //  super.onPreExecute();
    // Create a progressdialog
    //   mProgressDialog = new ProgressDialog(SubMenu.this);
    // Set progressdialog title
    //   mProgressDialog.setTitle("Categories of Main categories.....");
    // Set progressdialog message
    //  mProgressDialog.setMessage("Loading...");
    //  mProgressDialog.setIndeterminate(false);
    // Show progressdialog
    //  mProgressDialog.show();
    // }

    @Override
    protected Void doInBackground(Void... params) {
        // Create an array
        arraylist = new ArrayList<HashMap<String, String>>();
        // Retrieve JSON Objects from the given URL address
        jsonarray = JsonFunctions
                .getJSONfromURL("http://cloud....com/broccoli/menu_typeitem.php?id=" + getIntent().getStringExtra("id"));
        try {
            for (int i = 0; i < jsonarray.length(); i++) {
                HashMap<String, String> map = new HashMap<String, String>();
                jsonobject = jsonarray.getJSONObject(i);
                map.put("name", jsonobject.getString("name"));
                map.put("image", jsonobject.getString("image"));
                // Set the JSON Objects into the array
                arraylist.add(map);
            }
        } catch (JSONException e) {
            Log.e("Error", e.getMessage());
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(Void args) {
        // Locate the listview in listview_main.xml
        listview = (ListView) findViewById(R.id.list1);
        // Pass the results into ListViewAdapter.java
        adapter = new ListViewAdapter(SubMenu.this, arraylist);
        // Set the adapter to the ListView
        listview.setAdapter(adapter);
        listview.setOnItemClickListener(this);

    }
}

如果条件写这个。

if( name.getText().toString().equals("Bian‌‌ca Pizza")){

}else{

Toast.makeText(SubMenu.this, "hello", Toast.LENGTH_SHORT).show();

}

                     or

if( name.getText().toString().matches("Bian‌‌ca Pizza")){

}else{

Toast.makeText(SubMenu.this, "hello", Toast.LENGTH_SHORT).show();

}

如何匹配＆＃34;中的字符串值如果不是＆＃34;在android中的条件？

3 个答案: