如何保存列表视图状态并返回到该状态

Question

i am getting data from MySQL database in JSON form and showing in custom list view.list view is very lengthy. now i want that when i click on button in main activity it redirect me to the list view to the same position where i have left. thanks in advance.

    public class ShowParahDetail extends AppCompatActivity {
ProgressDialog pd;
CustomAdapter c;
ArrayList<Ayah_textAR> ar_ayahAR;
ArrayList<Ayah_textTR> ar_ayah_TR;
JazzyListView lv;
String intent_parah_ID;
String intent_parahName;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_show_parah_detail);
    intent_parah_ID=getIntent().getExtras().getString("parahID");
    intent_parahName=getIntent().getExtras().getString("parahName");
    setTitle(intent_parahName);
    pd = new ProgressDialog(ShowParahDetail.this, R.style.pdtheme);
    pd.setCancelable(false);
    pd.setProgressStyle(android.R.style.Widget_ProgressBar_Small);
    pd.show();
    lv= (JazzyListView) findViewById(R.id.lvparahDetail);

    ar_ayahAR = new ArrayList<>();
    ar_ayah_TR = new ArrayList<>();
    ShowDataAR();
    ShowTranslationUR();
}

private void ShowTranslationUR() {
    new Thread(new Runnable() {
        @Override
        public void run() {
            String RecievedString = "";
            HashMap<String, String> params = new HashMap<String, String>();
            params.put("parahid", intent_parah_ID);
            Network network = new Network("showParahTranslationUR.php", params);

            try {
                try {
                    Thread.sleep(500);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                RecievedString = network.ToRecieveDataFromWeb();
                JsonParsing jsonparsing = new JsonParsing(RecievedString);
                ArrayList<HashMap<String, String>> convertedarraydata = jsonparsing.ParsejsonArray(RecievedString);
                for (int i = 0; i < convertedarraydata.size(); i++) {
                    HashMap<String, String> positionHashmap;
                    positionHashmap = convertedarraydata.get(i);

                    String str_ayahText = positionHashmap.get("verseText");
                    String str_verseID = positionHashmap.get("verse_id");
                    String str_surahID = positionHashmap.get("surah_id");


                    Ayah_textTR ayahTR = new Ayah_textTR();
                    ayahTR.ayah_textTR = str_ayahText;
                    ayahTR.verse_id = str_verseID;
                    ayahTR.surah_id = str_surahID;
                    ar_ayah_TR.add(ayahTR);
                }

            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }).start();
}

private void ShowDataAR() {
    new Thread(new Runnable() {
        @Override
        public void run() {
            String RecievedString = "";
            HashMap<String, String> params = new HashMap<String, String>();
            params.put("parahid", intent_parah_ID);
            Network network = new Network("showParahDetails.php", params);

            try {
                try {
                    Thread.sleep(500);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                RecievedString = network.ToRecieveDataFromWeb();
                JsonParsing jsonparsing = new JsonParsing(RecievedString);
                ArrayList<HashMap<String, String>> convertedarraydata = jsonparsing.ParsejsonArray(RecievedString);
                for (int i = 0; i < convertedarraydata.size(); i++) {
                    HashMap<String, String> positionHashmap;
                    positionHashmap = convertedarraydata.get(i);
                    String str_ayahID = positionHashmap.get("verse_id");
                    String str_ayahText = positionHashmap.get("verseText");

                    Ayah_textAR ayahText = new Ayah_textAR();
                    ayahText.ayah_id = str_ayahID;
                    ayahText.ayah_textAR = str_ayahText;
                    ar_ayahAR.add(ayahText);
                }

            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (ShowParahDetail.this == null)
                    return;
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Parcelable state = lv.onSaveInstanceState();
                        lv.onRestoreInstanceState(state);
                        c = new CustomAdapter(ShowParahDetail.this, R.layout.cstm_parah, R.id.tv_parahNAME, ar_ayahAR);
                        lv.setAdapter(c);
                        if(pd!=null){
                            pd.dismiss();
                            pd = null;
                        }
                    }
                });
            }
        }
    }).start();
}


class CustomAdapter extends ArrayAdapter<Ayah_textAR> {
    public CustomAdapter(Context context, int resource, int textViewResourceId, ArrayList<Ayah_textAR> objects) {
        super(context, resource, textViewResourceId, objects);
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View v = inflater.inflate(R.layout.cstm_ayah, parent, false);

        final TextView tv_ayah_text = (TextView) v.findViewById(R.id.tv_ayahText);
        final TextView tv_ayahTR = (TextView) v.findViewById(R.id.tv_ayahTR);

        try {
            Ayah_textAR ayah = ar_ayahAR.get(position);
            tv_ayah_text.setText(ayah.ayah_id + " : " + ayah.ayah_textAR);
            Ayah_textTR parahTR = ar_ayah_TR.get(position);
            tv_ayahTR.setText(parahTR.ayah_textTR);
        }catch (Exception e){
            notifyDataSetChanged();
        }

        });
        return v;
    }
}
public class Ayah_textAR {
    String ayah_id;
    String ayah_textAR;
}
public class Ayah_textTR {
    String verse_id;
    String ayah_textTR;
    String surah_id;
}



@Override
public void onDestroy() {
    super.onDestroy();
    if (pd != null) {
        pd.dismiss();
        pd = null;
    }
}

}

Answer 1

You have three activities, A,B and C. Start your activity B with Intent. And also start your activity C with intent. Then, if you start your activity A and wish to save data which are exist in C, then start your activity A with intent. And don't finish your activity C. And if you want to resume activity C, just call onBackPressed() from your activity A. Don't forget finishing your activity A. For this call onFinish() .