Question

我有一个listview，我想在listitems超过200时刷新。我试过下面的代码，但它没有用。有人可以提出别的建议。我正在从其他类设置的Sharedpreference中检索listvalues。我是否还需要在计数后刷新首选项，以便我不在listview中再次设置这些值？如果是，那么基本问题如何获得正确的计数？

/*if (adapter.getCount() >= 200)
        {
            Log.d("FLUSHED", "flushed items");

            items.clear();
            adapter.notifyDataSetChanged();

            Toast.makeText(context, "As Value Crossed 10, Flushing List", Toast.LENGTH_SHORT).show();}*/

以下是我的完整代码：

public class LogListView extends ListActivity {
    /** Called when the activity is first created. */
    static String newString;
    private static EntryAdapterLog adapter;
    int clickCounter = 0;
    static ArrayList<Item> items = new ArrayList<Item>();
    static SharedPreferences preferences = null;
    private static Context context = null;
    static StringTokenizer tokens;
    static String first;
    private static String second;
    private JSONArray jsonarry = null;
    static String saveitems;
    private JSONObject jsonobject = null;
    private String subtitle;
    static String title;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        context = this;

        //startRepeatingTimer();
        adapter = new EntryAdapterLog(this, items);
        // items.add(new SectionItem("Log Report"));
        setListAdapter(adapter);

        if (adapter.getCount() != 0) {
            // Do nothing Adapter has value
        }
            /*if (adapter.getCount() >= 200)
        {
            Log.d("FLUSHED", "flushed items");

            items.clear();
            adapter.notifyDataSetChanged();

            Toast.makeText(context, "As Value Crossed 10, Flushing List", Toast.LENGTH_SHORT).show();
        }*/
        else {
            retreiveItems();
        }

    }

    @Override
    protected void onStart() {
      super.onStart();
    }

    // Method which will handle dynamic insertion
    public static void addItems(Context context) {

        //Get MM Failed Status
        preferences = context.getSharedPreferences("LOG",android.content.Context.MODE_PRIVATE);
        newString = preferences.getString("log", "");

        tokens = new StringTokenizer(newString, ",");
        first = tokens.nextToken();
        second = tokens.nextToken();

        if (first != null && second != null){
        items.add(new EntryItem(first, second));
        }
        //Get MM Failed Status ends

        adapter.notifyDataSetChanged();

    }
    // Method which will handle dynamic insertion ends

    @Override
    protected void onDestroy() {
        super.onDestroy();
        saveItems();
    }

    // Save ListItems if restarted
    protected static void saveItems() {
        SharedPreferences prefs = context.getSharedPreferences("prefName",Context.MODE_PRIVATE);
        Editor editor = prefs.edit();
        editor.putString("myList", new Gson().toJson(items).toString());
        editor.apply();
        Log.d("LOG", "Saved Items : " + items);
    }
    // Save ListItems if restarted ends

    // Retrieve ListItems if restarted
    protected void retreiveItems() {
        preferences = context.getSharedPreferences("prefName",android.content.Context.MODE_PRIVATE);
        saveitems = preferences.getString("myList", "");
        Log.d("LOG", "Retreived Items : " + saveitems);

        try {
            jsonarry = new JSONArray(saveitems);
        } catch (JSONException e) {
            e.printStackTrace();
        }

        if (jsonarry == null || jsonarry.length() == 0) {
            return;                                                                        //This checks before setting adapter onCreate if adapter is null
        }

        for (int i = 0; i < jsonarry.length(); i++) {

            try {
                jsonobject = jsonarry.getJSONObject(i);
            } catch (JSONException e) {
                e.printStackTrace();
            }

            // get all values here from JSONObject
            title = jsonobject.optString("title");
            subtitle = jsonobject.optString("subtitle");

            items.add(new EntryItem(title, subtitle));
            adapter.notifyDataSetChanged();

        }

    }
    // Retrieve ListItems if restarted ends

    // Counter for amount of period of time before flusing adapter
    protected void flushList(){

    }
    // Counter for amount of period of time before flusing adapter ends

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {

        if (!items.get(position).isSection()) {
            items.get(position);
            Toast.makeText(this, "You clicked " + position, Toast.LENGTH_SHORT).show();

        }

        super.onListItemClick(l, v, position, id);
    }
}

Answer 1

使用ArrayList items而不是Adapter

的计数

如果超过200，如何刷新列表项。（Adapter.getCount（））不起作用

1 个答案: