我制作了一个简单的提醒应用，其中将提醒，日期和时间存储在 SQLite数据库中。允许用户编辑并删除内容。当用户在对话框中编辑内容时，我的 recyclerView 未更新。 目前，我每次进行修改后都会重新加载活动。是否有任何方法可以更新 recyclerView 每个修改？请帮帮我。
我会给你我的代码。
public class Alarm extends Activity {
TextView title;
Button menu, info;
RecyclerView recycler_alarm;
SqliteHelper sqliteHelper;
Alarm_Adapter alarm_adapter;
LinearLayoutManager linearLayoutManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_alarm);
getAds();
initialise();
}
private void initialise() {
title = findViewById(R.id.currentMonth);
menu = findViewById(R.id.settings);
recycler_alarm=findViewById(R.id.recycler_alarm);
Typeface karthika = Typeface.createFromAsset(getAssets(),
"fonts/Karthika.ttf");
title.setTypeface(karthika);
menu.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(Alarm.this, MenuList.class);
startActivityForResult(intent, 1);
}
});
info = (Button) this.findViewById(R.id.addEvent);
info.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(Alarm.this, Info.class);
startActivity(intent);
}
});
loadAlarm();
}
private void loadAlarm()
{
sqliteHelper=new SqliteHelper(Alarm.this);
final List<Alarm_pojo> alarm_pojoList=sqliteHelper.getdata();
if(alarm_pojoList!=null&&!alarm_pojoList.isEmpty())
{
alarm_adapter=new Alarm_Adapter(Alarm.this,alarm_pojoList);
linearLayoutManager=new LinearLayoutManager(getApplicationContext());
recycler_alarm.setLayoutManager(linearLayoutManager);
alarm_adapter=new Alarm_Adapter(Alarm.this,alarm_pojoList, new Alarm_Adapter.MyAdapterListener() {
@Override
public void iconCancelOnClick(View v, final int position) {
Log.d("TAG", "iconCancelOnClick at position "+position);
final Dialog dialog=new Dialog(Alarm.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.alarm_deletion_dialog);
try {
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));
}
catch(NullPointerException e)
{
e.printStackTrace();
}
Button btn_yes=dialog.findViewById(R.id.btn_yes);
Button btn_no=dialog.findViewById(R.id.btn_no);
TextView txt_alarm=dialog.findViewById(R.id.txt_alarm);
String month_alarm=alarm_pojoList.get(position).getMonth_alarm();
String date_alarm=alarm_pojoList.get(position).getDate_alarm();
String month_name=null;
switch(month_alarm)
{
case "1":
month_name="ജനുവരി";
break;
case "2":
month_name="ഫെബ്രുവരി";
break;
case "3":
month_name="മാർച്ച്";
break;
case "4" :
month_name="ഏപ്രിൽ";
break;
case "5":
month_name="മെയ്";
break;
case "6":
month_name="ജൂൺ";
break;
case "7":
month_name="ജൂലൈ";
break;
case "8" :
month_name="ആഗസ്റ്റ്";
break;
case "9":
month_name="സെപ്റ്റംബർ";
break;
case "10":
month_name="ഒക്ടോബർ";
break;
case "11":
month_name="നവംബർ";
break;
case "12":
month_name="ഡിസംബര്";
break;
}
String txt_header=month_name+"\t"+date_alarm+"\t"+"ലെ അലാറം നീക്കം ചെയ്യണോ?";
txt_alarm.setText(txt_header);
btn_yes.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
int id=alarm_pojoList.get(position).getId();
sqliteHelper.clearAlarmList(id);
alarm_pojoList.remove(position);
recycler_alarm.setAdapter(alarm_adapter);
alarm_adapter.notifyDataSetChanged();
dialog.hide();
}
});
btn_no.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
dialog.dismiss();
// String id=String.valueOf(alarm_pojoList.get(position).getId());
// Toast.makeText(Alarm.this,id,Toast.LENGTH_SHORT).show();
}
});
dialog.show();
}
@Override
public void iconEditOnClick(View v, final int position)
{
sqliteHelper=new SqliteHelper(Alarm.this);
final List<Alarm_pojo> alarm_pojoList=sqliteHelper.getdata();
Log.d("TAG", "iconEditOnClick at position "+position);
int id=alarm_pojoList.get(position).getId();
final Dialog dialog=new Dialog(Alarm.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.alarm_edit_dialog);
try {
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));
}
catch(NullPointerException e)
{
e.printStackTrace();
}
Button btn_yes=dialog.findViewById(R.id.btn_yes);
Button btn_no=dialog.findViewById(R.id.btn_no);
TextView txt_editalarm=dialog.findViewById(R.id.txt_editalarm);
final TextView txt_month=dialog.findViewById(R.id.txt_month);
ImageView img_datepicker=dialog.findViewById(R.id.img_datepicker);
final TextView txt_hr=dialog.findViewById(R.id.txt_hr);
final EditText et_reminders=dialog.findViewById(R.id.et_reminders);
ImageView img_timepicker=dialog.findViewById(R.id.img_timepicker);
String month_alarm=alarm_pojoList.get(position).getMonth_alarm();
String date_alarm=alarm_pojoList.get(position).getDate_alarm();
String year_alarm=alarm_pojoList.get(position).getYear_alarm();
String time_alarm=alarm_pojoList.get(position).getTime_alarm();
final String reminder=alarm_pojoList.get(position).getReminder();
final String selected_date=date_alarm+"-"+month_alarm+"-"+year_alarm;
String month_name=null;
switch(month_alarm)
{
case "1":
month_name="ജനുവരി";
break;
case "2":
month_name="ഫെബ്രുവരി";
break;
case "3":
month_name="മാർച്ച്";
break;
case "4" :
month_name="ഏപ്രിൽ";
break;
case "5":
month_name="മെയ്";
break;
case "6":
month_name="ജൂൺ";
break;
case "7":
month_name="ജൂലൈ";
break;
case "8" :
month_name="ആഗസ്റ്റ്";
break;
case "9":
month_name="സെപ്റ്റംബർ";
break;
case "10":
month_name="ഒക്ടോബർ";
break;
case "11":
month_name="നവംബർ";
break;
case "12":
month_name="ഡിസംബര്";
break;
}
String text_header=month_name+"\t"+date_alarm+"\t"+"ലെ അലാറം നിങ്ങൾക്ക് എഡിറ്റുചെയ്യണോ?";
txt_editalarm.setText(text_header);
txt_month.setText(selected_date);
txt_hr.setText(time_alarm);
et_reminders.setText(reminder);
img_timepicker.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Calendar mCurrentTime=Calendar.getInstance();
int hour=mCurrentTime.get(Calendar.HOUR_OF_DAY);
int minute=mCurrentTime.get(Calendar.MONTH);
TimePickerDialog timePickerDialog;
timePickerDialog=new TimePickerDialog(Alarm.this, new TimePickerDialog.OnTimeSetListener() {
@Override
public void onTimeSet(TimePicker timePicker, int selectedHour, int selectedMinute) {
String convert_hour=convertTime(selectedHour);
String convert_minute=convertTime(selectedMinute);
String time_selected=convert_hour+":"+convert_minute;
final TextView txt_hr=dialog.findViewById(R.id.txt_hr);
txt_hr.setText(time_selected);
}
},hour,minute,true);
timePickerDialog.setTitle("Select Time");
timePickerDialog.show();
}
});
img_datepicker.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
final Calendar myCalendar = Calendar.getInstance();
Calendar calendar = Calendar.getInstance();
//Setting maximum year as current year
calendar.set(2019, 11, 31);
DatePickerDialog.OnDateSetListener date = new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
myCalendar.set(Calendar.YEAR, year);
myCalendar.set(Calendar.MONTH, monthOfYear);
myCalendar.set(Calendar.DAY_OF_MONTH, dayOfMonth);
String myFormat = "dd-MM-yyyy"; //In which you need put here
SimpleDateFormat sdf = new SimpleDateFormat(myFormat, Locale.US);
String selected_date=sdf.format(myCalendar.getTime());
String[] out=selected_date.split("-");
String dateconverted=out[0];
String monthconverted=out[1];
String yearconverted=out[2];
//Formating the date and month selected.
//Removing intial zero appearing in the date and month selection
String actual_date=convertSelection(dateconverted);
String actual_month=convertSelection(monthconverted);
String formatedvalue=actual_date+"-"+actual_month+"-"+yearconverted;
//Setting the actual date on the textview.
txt_month.setText(formatedvalue);
}
};
DatePickerDialog datePickerDialog=new DatePickerDialog(Alarm.this, R.style.MyPickerDialogTheme, date, myCalendar
.get(Calendar.YEAR), myCalendar.get(Calendar.MONTH),
myCalendar.get(Calendar.DAY_OF_MONTH));
//For avoiding the past days.
datePickerDialog.getDatePicker().setMinDate(System.currentTimeMillis() - 10000);
//Restricting date picker to show only current year.
datePickerDialog.getDatePicker().setMaxDate(calendar.getTimeInMillis()+10000);
datePickerDialog.show();
}
});
btn_yes.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String month_selected = txt_month.getText().toString();
String time_selected = txt_hr.getText().toString();
String reminders = et_reminders.getText().toString();
int id=alarm_pojoList.get(position).getId();
if (!month_selected.equals("") && !time_selected.equals("") && !reminders.equals(""))
{
int result= sqliteHelper.updateAlarm(month_selected,time_selected,reminders,id);
if(result>0)
{
finish();
startActivity(getIntent());
Toast.makeText(Alarm.this,"Updated",Toast.LENGTH_SHORT).show();
dialog.hide();
}
}
else
{
Toast.makeText(Alarm.this,"Not Updated. Missing input fields!",Toast.LENGTH_SHORT).show();
}
}
});
btn_no.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
dialog.hide();
}
});
dialog.show();
}
});
recycler_alarm.setAdapter(alarm_adapter);
alarm_adapter.notifyDataSetChanged();
}
else
{
Toast.makeText(Alarm.this,"No Alarms added yet!..",Toast.LENGTH_SHORT).show();
}
}
private String convertSelection(String dateconverted) {
int date=Integer.parseInt(dateconverted);
if(date>=10)
{
return String.valueOf(date);
}
else
{
return Integer.valueOf(dateconverted).toString();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1) {
if (resultCode == RESULT_OK) {
finish();
}
}
}
@Override
public void onBackPressed() {
Intent intent = new Intent(Alarm.this, CalendarActivity.class);
finish();
startActivity(intent);
}
private void getAds() {
AdView adView = findViewById(R.id.adView1);
AdRequest adRequest = new AdRequest.Builder().build();
adView.loadAd(adRequest);
}
private String convertTime(int time_selected) {
if(time_selected>=10)
{
return String.valueOf(time_selected);
}
else
{
return "0" + String.valueOf(time_selected);
}
}
}
强文本
答案 0 :(得分：1)
您不必每次只在适配器中添加新值时设置适配器 alarm_pojoList，然后调用adapter.notifyDataSetChanged（）
并且最好使用notifyiteminserted（）代替notifyDataSetChanged并传递列表的大小以将值添加到列表的最后一个位置，或者如果需要将其添加到列表的顶部则传递0