检查下面的更新。
我正在制作一个用于爬楼梯挑战的应用程序，用于跟踪所走步数的日期和数量(用户输入，而不是自动)。我有一个 ArrayList ，它存储包含以下三个变量的对象:
String date
Int steps
Instant timeStamp
该应用程序有两个输入按钮，一个用于整数步长输入，一个用于日期选择。创建了一个简单的方法，可以按所选日期和几个视觉指示器来过滤可见列表，这些指示器显示您的每日进度与当天爬楼梯的每日目标。
我使用 Instant 变量作为时间戳来尝试解决 OnClickListener 从已过滤列表中选择项目位置而不是未过滤列表中相应项目的问题。为此，我使用 OnClickListener 报告的位置从已过滤的 ArrayList 中的关联项目中获取时间戳变量，然后将该时间戳与未过滤的 ArrayList 中的项目进行比较，并获取匹配项目的索引.
当您选择日期时，所有过滤的 ArrayList 都会正确显示在 RecyclerView 中。
问题出在删除项目上。如果我仅向一个日期添加项目，那么您可以按照预期删除和添加项目。
App function without date change (gif)
如果我添加到一个日期，然后添加到另一个日期，当它们正确显示时，这些项目将从正确的位置删除，但在您第一次添加项目的日期，无论该日期是否是当前选择的日期。
App function with changing date (gif)
我觉得我在这里错过了一些相对简单的东西，而且我的大脑太饱和了这个项目而看不到它。
主要 Activity :
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private ExampleAdapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
Date temp_curr_date = Calendar.getInstance().getTime();
SimpleDateFormat df = new SimpleDateFormat("dd-MMM-yyyy");
String sel_date = df.format(temp_curr_date);
String curr_date = df.format(temp_curr_date);
double daily_total;
int progress = 0;
double daily_goal = 7.5;
TextView textView1;
TextView textView2;
TextView textViewFlights;
ProgressBar pb;
List<ExampleItem> mExampleList;
List<ExampleItem> filteredList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ----- LOAD SAVED ARRAY LIST -----
loadData();
// ----- SET VARIABLES -----
daily_total = totalOutput(mExampleList, sel_date);
textView1 = findViewById(R.id.total);
textView1.setText(String.valueOf(daily_total));
textViewFlights = findViewById(R.id.flights);
pb = findViewById(R.id.progress_bar);
pb.setProgress(getProgress(mExampleList, sel_date), true);
// ----- BUILD RECYCLERVIEW -----
buildRecyclerView();
filter(sel_date);
// ----- ADD STEPS DIALOGUE -----
setAddStepButton();
// ----- CALENDAR DIALOGUE -----
setDateChangeButton();
}
public double totalOutput(List<ExampleItem> steps, String date) {
try{
int temp_total = 0;
double flight_total;
for (int a = 0; a < steps.size(); a++) {
if (date.equals(steps.get(a).getText1()))
temp_total += steps.get(a).getText2();
}
flight_total = round(temp_total / 16.0, 2);
return flight_total;
} catch (Exception e){
return 0.0;
}
}
public static double round(double value, int places) {
if (places < 0) throw new IllegalArgumentException();
BigDecimal bd = new BigDecimal(value);
bd = bd.setScale(places, RoundingMode.HALF_UP);
return bd.doubleValue();
}
public static int toInt(double value) {
BigDecimal bd = new BigDecimal(value);
bd = bd.setScale(0, RoundingMode.HALF_UP);
return bd.intValue();
}
public static Date getDate(int year, int month, int day) {
Calendar cal = Calendar.getInstance();
cal.set(Calendar.YEAR, year);
cal.set(Calendar.MONTH, month);
cal.set(Calendar.DAY_OF_MONTH, day);
cal.set(Calendar.HOUR_OF_DAY, 0);
cal.set(Calendar.MINUTE, 0);
cal.set(Calendar.SECOND, 0);
cal.set(Calendar.MILLISECOND, 0);
return cal.getTime();
}
private void saveData(){
SharedPreferences sharedPreferences = getSharedPreferences("shared preferences", MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
Gson gson = new Gson();
String json = gson.toJson(mExampleList);
editor.putString("task list", json);
editor.apply();
}
private void loadData(){
SharedPreferences sharedPreferences = getSharedPreferences("shared preferences", MODE_PRIVATE);
Gson gson = new Gson();
String json = sharedPreferences.getString("task list", null);
Type type = new TypeToken<ArrayList<ExampleItem>>() {}.getType();
mExampleList = gson.fromJson(json, type);
if (mExampleList == null){
mExampleList = new ArrayList<>();
}
}
private int getProgress(List<ExampleItem> steps, String date){
int daily_progress_int;
try{
int temp_progress = 0;
double flight_total;
for (int a = 0; a < steps.size(); a++) {
if (date.compareTo(steps.get(a).getText1()) == 0)
temp_progress += steps.get(a).getText2();
}
flight_total = round(temp_progress / 16.0, 2);
daily_progress_int = toInt((flight_total/daily_goal)*100);
return daily_progress_int;
} catch (Exception e){
return 0;
}
}
private void addProgress(double x, int prog){
int daily_progress_int = toInt((x/daily_goal)*100);
if (progress <= 100-daily_progress_int){
progress = progress + prog;
pb = findViewById(R.id.progress_bar);
pb.setProgress(daily_progress_int, true);
} else if (progress + daily_progress_int > 100){
pb = findViewById(R.id.progress_bar);
pb.setProgress(100, true);
}
}
private void removeProgress(double x, int prog){
int daily_progress_int = toInt((x/daily_goal)*100);
progress = progress - prog;
if (progress <= 100) {
pb = findViewById(R.id.progress_bar);
pb.setProgress(daily_progress_int, true);
} else {
pb = findViewById(R.id.progress_bar);
pb.setProgress(0, true);
}
}
public void addItem(String date, int steps, Instant ts){
mExampleList.add(new ExampleItem(date, steps, ts));
filter(sel_date);
}
public void removeItem(final int position){
final AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
View viewInflated = LayoutInflater.from(MainActivity.this).inflate(R.layout.confirm, (ViewGroup) findViewById(android.R.id.content), false);
builder.setCancelable(true);
builder.setView(viewInflated);
builder.setPositiveButton("Yup",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
mExampleList.remove(position);
mAdapter.notifyDataSetChanged(position);
filter(sel_date);
daily_total = totalOutput(mExampleList, sel_date);
textView1 = findViewById(R.id.total);
textView1.setText(String.valueOf(daily_total));
removeProgress(daily_total,progress);
if (daily_total == 1.0){
textViewFlights.setText("flight");
} else {
textViewFlights.setText("flights");
}
saveData();
}
});
builder.setNegativeButton("Nope", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
});
AlertDialog dialog = builder.create();
dialog.show();
}
public void buildRecyclerView(){
mRecyclerView = findViewById(R.id.recyclerView);
mRecyclerView.setHasFixedSize(true);
mLayoutManager = new LinearLayoutManager(this);
mAdapter = new ExampleAdapter(mExampleList);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
mAdapter.setOnItemClickListener(new ExampleAdapter.OnItemClickListener() {
@Override
public void onItemClick(int position) {
Instant test = filteredList.get(position).getTimeStamp();
for (ExampleItem item : mExampleList){
if (test.compareTo(item.getTimeStamp()) == 0){
removeItem(mExampleList.indexOf(item));
}
});
}
public void filter(String text){
filteredList = new ArrayList<>();
for (ExampleItem item : mExampleList){
if (item.getText1().toLowerCase().contains(text.toLowerCase())){
filteredList.add(item);
}
}
mAdapter.filterList(filteredList);
}
public void setAddStepButton(){
FloatingActionButton fab = findViewById(R.id.addSteps);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
View viewInflated = LayoutInflater.from(MainActivity.this).inflate(R.layout.add_steps, (ViewGroup) findViewById(android.R.id.content), false);
// Step input
final EditText input = viewInflated.findViewById(R.id.input);
builder.setView(viewInflated);
// OK Button
builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
if (input.getText().length() != 0) {
try {
int in = Integer.parseInt(String.valueOf(input.getText()));
if (in > 0) {
Instant timeStamp = Instant.now();
addItem(sel_date, in, timeStamp);
dialog.dismiss();
} else {
dialog.cancel();
}
} catch (Exception e) {
dialog.cancel();
}
daily_total = totalOutput(mExampleList, sel_date);
textView1 = findViewById(R.id.total);
textView1.setText(String.valueOf(daily_total));
addProgress(daily_total, progress);
mAdapter.notifyDataSetChanged();
filter(sel_date);
if (daily_total == 1.0){
textViewFlights.setText("flight");
} else {
textViewFlights.setText("flights");
}
saveData();
} else{
dialog.cancel();
}
}
});
// Cancel Button
builder.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
builder.show();
}
});
}
public void setDateChangeButton(){
FloatingActionButton fabcal = findViewById(R.id.calendarButton);
fabcal.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view) {
LayoutInflater inflater = (LayoutInflater)getApplicationContext().getSystemService
(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout ll= (LinearLayout)inflater.inflate(R.layout.calendar, null, false);
CalendarView cv = (CalendarView) ll.getChildAt(0);
long milliseconds = 0;
try {
Date d = df.parse(sel_date);
milliseconds = d.getTime();
} catch (ParseException e) {
e.printStackTrace();
}
cv.setDate(milliseconds);
cv.setOnDateChangeListener(new CalendarView.OnDateChangeListener() {
@Override
public void onSelectedDayChange(
@NonNull CalendarView view,
int year,
int month,
int dayOfMonth)
{
Date temp_sel_date = getDate(year, month, dayOfMonth);
sel_date = df.format(temp_sel_date);
textView2 = findViewById(R.id.daily_total);
if (sel_date.equals(curr_date)){
textView2.setText("Today");
} else {
String dt_day = (String) DateFormat.format("dd", temp_sel_date);
String dt_month = (String) DateFormat.format("MMM", temp_sel_date);
textView2.setText(dt_month + " " + dt_day);
}
daily_total = totalOutput(mExampleList, sel_date);
textView1 = findViewById(R.id.total);
textView1.setText(String.valueOf(daily_total));
pb = findViewById(R.id.progress_bar);
pb.setProgress(getProgress(mExampleList, sel_date), true);
mAdapter.notifyDataSetChanged();
filter(sel_date);
}
});
new AlertDialog.Builder(MainActivity.this)
.setView(ll)
.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
dialog.dismiss();
}
}
).show();
}
});
}
}
适配器类:
public class ExampleAdapter extends RecyclerView.Adapter<ExampleAdapter.ExampleViewHolder> {
private static List<ExampleItem> mExampleList;
private static List<ExampleItem> exampleListFull;
private OnItemClickListener mListener;
public interface OnItemClickListener{
void onItemClick(int position);
}
public void setOnItemClickListener(OnItemClickListener listener){
mListener = listener;
}
public static class ExampleViewHolder extends RecyclerView.ViewHolder {
public TextView mTextView1;
public ImageView mDeleteImage;
public ExampleViewHolder(View itemView, final OnItemClickListener listener) {
super(itemView);
mTextView1 = itemView.findViewById(R.id.textView);
mDeleteImage = itemView.findViewById(R.id.image_delete);
mDeleteImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (listener != null){
int position = getAdapterPosition();
if (position != RecyclerView.NO_POSITION){
Instant test = mExampleList.get(position).getTimeStamp();
for (ExampleItem item : exampleListFull){
int compare = test.compareTo(item.getTimeStamp());
if (compare == 0){
int delIndex = exampleListFull.indexOf(item);
position = delIndex;
}
}
listener.onItemClick(position);
}
}
}
});
}
}
public ExampleAdapter(List<ExampleItem> exampleList){
this.mExampleList = exampleList;
exampleListFull = new ArrayList<>(exampleList);
}
@NonNull
@Override
public ExampleViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int i) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.example_item, parent, false);
ExampleViewHolder evh = new ExampleViewHolder(v, mListener);
return evh;
}
@Override
public void onBindViewHolder(@NonNull ExampleViewHolder holder, int position) {
ExampleItem currentItem = mExampleList.get(position);
if (currentItem.getText2() == 1.0){
holder.mTextView1.setText(currentItem.getText2() + " step");
} else {
holder.mTextView1.setText(currentItem.getText2() + " steps");
}
}
@Override
public int getItemCount() {
return mExampleList.size();
}
public void filterList(List<ExampleItem> filteredList){
mExampleList = filteredList;
notifyDataSetChanged();
}
}
如果有人有任何想法，我很乐意听取您的意见!
更新:包含的代码现在反射(reflect)了用户建议的更改并且功能齐全。
最佳答案
关于java - 如何使用过滤的 RecyclerView 和 OnClickListener 从 ArrayList 中删除项目，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56765750/