我正在尝试创建一个注重色彩变化的笔记应用程序。在其中一个活动中,我试图实现对注解的项添加和删除
活动的图片。
项目添加显然按预期工作。问题是删除,它是非常不一致的:当我删除所有的项目开始从最后一个向上,一切工作正常;如果我按另一个顺序删除项目,适配器就会出错,不要总是删除正确的项目,并在删除最后一个项目时崩溃。
我查了一下,找到了一些可能的解决方案(在这里或其他网站),但找不到解决方案,或者,我想。
我在适配器additem()和removItem()中创建了方法,以便在类中完成任何更改。也许我误解了一个概念或者遗漏了什么?提前谢谢!
因为我还没有实现一些特性,所以缺少一些接口或代码保护
活动代码
package com.example.colornoteplus;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import java.text.DateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Objects;
public class CheckListNoteActivity extends AppCompatActivity{
// note editable views
private EditText titleView;
private TextView titleCharacterCount;
private ImageButton colorView;
private RecyclerView contentView;
private FloatingActionButton fab;
CheckListAdapter adapter;
// toolbar
private Toolbar toolbar;
// Current note
private CheckListNote note;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getNoteFromIntent();
note.getContent().add(new CheckListItem("ONE"));
note.getContent().add(new CheckListItem("TWO"));
note.getContent().add(new CheckListItem("THREE"));
note.getContent().add(new CheckListItem("FOUR"));
note.getContent().add(new CheckListItem("FIVE"));
changeViewsColor(0);
}
// Method used to add menus and configure button action
// like OnClickListeners ...
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Create a submenu for sorting purpose
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu_check_list_activity,menu);
return super.onCreateOptionsMenu(menu);
}
// get note from the intent
private void getNoteFromIntent(){
if (!getIntent().getStringExtra(Statics.KEY_NOTE_ACTIVITY).equals(Statics.NOTE_DEFAULT_UID)){
note = MySharedPreferences.LoadCheckListNoteFromSharedPreferences(getIntent().getStringExtra(Statics.KEY_NOTE_ACTIVITY),getApplicationContext());
} else {
note = new CheckListNote();
}
}
private void changeViewsColor(int color){
// set the global theme
setTheme(StyleManager.getTheme(color));
// set the appropriate layout
setContentView(R.layout.activity_check_list_note);
// change status bar color
getWindow().setStatusBarColor(getResources().getColor(StyleManager.getThemeColor(color)));
// set up FAB action
fab = findViewById(R.id.fab_add_item);
fab.setOnClickListener(view -> onFabClickListener());
// setting the toolbar
toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
toolbar.setBackgroundColor(getResources().getColor(StyleManager.getThemeColor(color)));
Objects.requireNonNull(getSupportActionBar()).setDisplayHomeAsUpEnabled(true);
// setting the note title
titleView = findViewById(R.id.note_title_view);
titleView.setText("");
titleView.setTextColor(getResources().getColor(StyleManager.getThemeColorDark(color)));
titleView.setHintTextColor(getResources().getColor(StyleManager.getThemeColorLight(color)));
// setting the character counter for the note title
titleCharacterCount = findViewById(R.id.note_title_characters);
String m = titleView.getText().toString().trim().length()+ getString(R.string.text_divider)+ getResources().getInteger(R.integer.title_max_length);
titleCharacterCount.setText(m);
titleCharacterCount.setTextColor(getResources().getColor(StyleManager.getThemeColor(color)));
titleView.addTextChangedListener(new TextWatcher()
{
@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
{
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int aft)
{
}
@Override
public void afterTextChanged(Editable s)
{
// this will show characters remaining
String msg = titleView.getText().toString().length()+ getString(R.string.text_divider)+ getResources().getInteger(R.integer.title_max_length);
titleCharacterCount.setText(msg);
}
});
// setting the color view
colorView = findViewById(R.id.note_color_view);
colorView.setOnClickListener(view -> buildColorPickDialog());
colorView.setBackgroundResource(StyleManager.getBackground(color));
adapter = new CheckListAdapter(getApplicationContext(),note.getContent(),color);
adapter.setOnItemClickListener(new CheckListAdapter.OnItemClickListener() {
@Override
public void onChecked(int position) {
Toast.makeText(CheckListNoteActivity.this, "Checked item: " +position, Toast.LENGTH_SHORT).show();
}
@Override
public void onUnchecked(int position) {
Toast.makeText(CheckListNoteActivity.this, "Unchecked item: " +position, Toast.LENGTH_SHORT).show();
}
@Override
public void onSetPriority(int position) {
}
@Override
public void onSetReminder(int position) {
}
@Override
public void onDelete(int position) {
adapter.removeItem(position);
Toast.makeText(CheckListNoteActivity.this, "List has "+note.getContent().size()+" elements", Toast.LENGTH_SHORT).show();
}
});
contentView = findViewById(R.id.note_content_view);
contentView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
contentView.setAdapter(adapter);
}
private void switchColor(int color){
String tempTitle = titleView.getText().toString().trim();
changeViewsColor(color);
titleView.setText(tempTitle);
}
// build the color picker dialog
private void buildColorPickDialog(){
FragmentPickColor fragment = new FragmentPickColor(new ColorAdapter(),5,note.getColor());
fragment.show(getSupportFragmentManager(),Statics.TAG_FRAGMENT_COLOR_PICK);
fragment.setOnItemClickListener(new ColorAdapter.OnItemClickListener() {
@Override
public void OnClickListener(int position) {
note.setColor(position);
switchColor(position);
fragment.dismiss();
}
@Override
public void OnLongClickListener(int position) {
}
});
}
private void onFabClickListener(){
FragmentAddCheckListItem fragment = new FragmentAddCheckListItem(note.getColor());
fragment.show(getSupportFragmentManager(),Statics.TAG_FRAGMENT_ADD_CHECK_LIST_ITEM);
fragment.setOnClickListener(new FragmentAddCheckListItem.OnClickListener() {
@Override
public void onConfirmClickListener() {
fragment.getItem().setDescription(fragment.getInputText());
adapter.addItem(fragment.getItem(),0);
fragment.dismiss();
}
@Override
public void onSetPriorityClickListener() {
}
@Override
public void onSetDueTimeClickListener() {
FragmentDatePicker datePicker = new FragmentDatePicker();
datePicker.show(getSupportFragmentManager(),Statics.TAG_FRAGMENT_DATE_PICKER);
datePicker.setOnDateSet((year, month, day) -> {
Calendar c = Calendar.getInstance();
c.set(Calendar.YEAR,year);
c.set(Calendar.MONTH,month);
c.set(Calendar.DAY_OF_MONTH,day);
fragment.getItem().setDueDate(c.getTime().getTime());
fragment.setDueTimeText(DateFormat.getDateInstance().format(new Date(fragment.getItem().getDueDate())));
});
}
});
}
}
适配器
package com.example.colornoteplus;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.constraintlayout.widget.ConstraintLayout;
import androidx.recyclerview.widget.RecyclerView;
import java.text.DateFormat;
import java.util.ArrayList;
import java.util.Date;
public class CheckListAdapter extends RecyclerView.Adapter<CheckListAdapter.MyViewHolder> {
public CheckListAdapter(Context context,ArrayList<CheckListItem> list, int color) {
this.list = list;
this.color = color;
this.context = context;
}
final private ArrayList<CheckListItem> list;
final private int color;
final private Context context;
private OnItemClickListener listener;
@NonNull
@Override
public CheckListAdapter.MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
return new CheckListAdapter.MyViewHolder(LayoutInflater.
from(parent.getContext()).
inflate(R.layout.item_check_list,parent,false));
}
@Override
public void onBindViewHolder(@NonNull CheckListAdapter.MyViewHolder holder, int position) {
CheckListItem currentItem = list.get(position);
holder.background.setBackgroundResource(StyleManager.getBackgroundLight(color));
holder.checkBox.setOnCheckedChangeListener((compoundButton, b) -> {
if (b) listener.onChecked(position);
else listener.onUnchecked(position);
});
holder.title.setTextColor(context.getResources().getColor(StyleManager.getThemeColorDark(color)));
holder.title.setHintTextColor(context.getResources().getColor(StyleManager.getThemeColor(color)));
assert currentItem != null;
holder.title.setText(currentItem.getDescription().trim());
holder.dueTimeText.setTextColor(context.getResources().getColor(StyleManager.getThemeColor(color)));
holder.dueTimeText.setText(currentItem.getDoneDate() != -1 ? DateFormat.getDateInstance().format(new Date(currentItem.getDueDate())) : context.getString(R.string.set_reminder));
holder.dueTimeText.setOnClickListener(view -> listener.onSetReminder(position));
holder.priorityText.setTextColor(context.getResources().getColor(StyleManager.getThemeColor(color)));
holder.priorityText.setText(currentItem.priorityToString(context));
holder.priorityText.setOnClickListener(view -> listener.onSetPriority(position));
holder.delete.setBackgroundResource(StyleManager.getBackground(color));
holder.delete.setOnClickListener(view -> {
// listener.onDelete(position);
removeItem(position);
});
}
@Override
public int getItemCount() {
return list.size();
}
public static class MyViewHolder extends RecyclerView.ViewHolder{
CheckBox checkBox;
ConstraintLayout background;
EditText title;
ImageButton delete;
TextView priorityText,dueTimeText;
public MyViewHolder(@NonNull View itemView) {
super(itemView);
checkBox = itemView.findViewById(R.id.item_check_box);
title = itemView.findViewById(R.id.item_title);
dueTimeText = itemView.findViewById(R.id.item_due_time_text);
priorityText = itemView.findViewById(R.id.item_priority_text);
delete = itemView.findViewById(R.id.item_delete);
background = itemView.findViewById(R.id.item_background);
}
}
public void addItem(CheckListItem item,int position){
if (position < 0){
list.add(item);
notifyItemInserted(list.size()-1);
}
else {
list.add(position,item);
notifyItemInserted(position);
}
}
public void removeItem(int position){
list.remove(position);
notifyItemRemoved(position);
}
public void setOnItemClickListener(OnItemClickListener listener){
this.listener = listener;
}
public interface OnItemClickListener{
void onChecked(int position);
void onUnchecked(int position);
void onSetPriority(int position);
void onSetReminder(int position);
void onDelete(int position);
}
}
1条答案
按热度按时间1u4esq0p1#
而且在
onBindViewHolder
使用holder.getAdapterPosition()
而不是position
在你的听众中: