Question

我正在使用从SQLite浏览器中检索的项目（类别）的这个列表视图，现在我希望用户点击其中一个类别，例如，如果用户点击餐馆类别，我想取id并在新的意图活动中将数据库中的所有餐馆检索到另一个列表中。

此处的问题是，类别中的每个项目都显示相同的结果。

类别活动

public class WhereToGo extends ListActivity {

public final static String ID_EXTRA="com.example.buttontest._id";
  DataBaseHelper db_con;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.activity_where_to_go);

}

 @Override
    public void onStart(){
     super.onStart();
     db_con = new DataBaseHelper(this);
        listNotes();
    }
@SuppressWarnings("deprecation")
private void listNotes(){
     SQLiteDatabase db = db_con.getReadableDatabase();
     try {
         Cursor c = db.rawQuery("SELECT name as '_id' " +
     "FROM category ",null );
         final ListAdapter noteAdapter = new SimpleCursorAdapter(this,android.R.layout.simple_list_item_2, c,new String[] {"_id"},new int[] {android.R.id.text1});
         this.setListAdapter(noteAdapter);
     } finally {
     db.close();
     }
    }
 @Override
    protected void onListItemClick(ListView l, View v, int position, long id){
     super.onListItemClick(l, v, position, id);
     // Intent:
     Intent i = new Intent(this, ShowWhereToGo.class);
     i.putExtra(ID_EXTRA, String.valueOf(id));
     startActivity(i);

    }
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.where_to_go, menu);
    return true;
}

}

ShowWhereToGo

public class ShowWhereToGo extends Activity {

     DataBaseHelper dbhelper;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_show_where_to_go);

        String[] from = new String[] { "name" };  
          int[] to = new int[] { R.id.TextView1 };  

          dbhelper = new DataBaseHelper(this);  
          try {  
           dbhelper.createDataBase();  
          } catch (IOException e) {  
           // TODO Auto-generated catch block  
           e.printStackTrace();  
          }  

          Cursor c = dbhelper.getFacilityData();  

          @SuppressWarnings("deprecation")
        SimpleCursorAdapter adapter = new SimpleCursorAdapter(getApplicationContext(), R.layout.activity_tab, c, from, to);  

           ListView list = (ListView) findViewById(R.id.listView1);  

           list.setAdapter(adapter);  
           list.setOnItemClickListener(new OnItemClickListener() {   
                public void onItemClick(AdapterView<?> parent, View view,int position, long id) {      
                    Intent myIntent = new Intent(view.getContext(), CheckinActivity.class); 
                    myIntent.putExtra("id", position);
                    startActivityForResult(myIntent, 0); // display SubView.class               }
            }

                @SuppressWarnings("unused")
                public void onItemClick1(AdapterView<?> arg0, View arg1,
                        int arg2, long arg3) {
                    // TODO Auto-generated method stub

                }}); 
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.show_where_to_go, menu);
        return true;
    }

}

Answer 1

尝试更改此行：

i.putExtra(ID_EXTRA, String.valueOf(id));

为：

i.putExtra(ID_EXTRA, position);

Answer 2

1-在listNotes方法中，取noteAdapter并将其设为全局变量。 2-在onListItemClick方法中将此i.putExtra(ID_EXTRA, String.valueOf(id));更改为i.putExtra(ID_EXTRA, noteAdapter.getItem(position));

**你必须传递* _id *的值，但是你在这里传递数组中String对象的is，这与你要搜索的id完全无关。

显示数据库中的ListView项

2 个答案: