我有几个星期没能解决的问题。我有一个应用程序，可以在单击按钮时添加两个 EditText 和一个 CheckBox。但是，每当我在 EditTexts 中键入一些内容，然后向下滚动时，当我向上滚动时内容就会消失。我无法解决这个问题。我发现了其他一些非常相似的帖子，但是我已经尝试了我能找到的所有解决方案，但似乎还没有一个对我有用。这是我发现的几个类似的帖子:
我最近对我的程序做了一些修改，试图解决这个问题。我将 ArrayList 添加到我的 MainActivity 并将其传递到我的适配器。我还制作了两个自定义文本监听器，其中 onTextChanged，我将字符串添加到 ArrayList。然后，在 onBindViewHolder 中，我更新文本监听器中的位置，然后在该位置将文本设置为 ArrayList 中的字符串。但是，这会产生一些奇怪的错误。现在，当我将内容添加到 EditText 并向下滚动时，它会将其添加到多个 EditText，甚至更改其中一些的内容。我不确定如何解决这个问题。
另外，另一方面，我为应用程序启用了拖放和滑动关闭功能。因此，如果您有解决方案，请也考虑到这一点。谢谢!
主 Activity
import android.content.ClipData;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.helper.ItemTouchHelper;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private ArrayList<ListItems> itemsList;
private RecyclerView mRecyclerView;
private MyRecyclerAdapter adapter;
private List<String> courseStrings = new ArrayList<>();
private List<String> creditStrings = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
courseStrings.add("");
creditStrings.add("");
// Toast variable in order to fix toast queueing issue.
final Toast toast = Toast.makeText(MainActivity.this, "", Toast.LENGTH_SHORT);
// For the recycler view.
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
final LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
itemsList = new ArrayList<>();
adapter = new MyRecyclerAdapter(MainActivity.this, itemsList, courseStrings, creditStrings);
mRecyclerView.setAdapter(adapter);
mRecyclerView.setLayoutManager(linearLayoutManager);
// For the addCourse button.
final Button addCourse = (Button) findViewById(R.id.addCourse);
addCourse.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
adapter.createListItem(new ListItems(null, null, false), toast);
toast.setText("New course added");
toast.show();
}
});
final Button clearAll = (Button) findViewById(R.id.clearAll);
clearAll.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// In order to clear the list.
if (itemsList.size() == 0) {
toast.setText("All courses have already been cleared.");
toast.show();
} else {
adapter.clearAdapter();
toast.setText("All courses have been cleared.");
toast.show();
}
}
});
// For the drag and drop/swipe to dismiss.
ItemTouchHelper itemTouchHelper = new ItemTouchHelper(
new ItemTouchHelper.SimpleCallback(ItemTouchHelper.UP | ItemTouchHelper.DOWN,
ItemTouchHelper.LEFT) {
public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) {
final int fromPos = viewHolder.getAdapterPosition();
final int toPos = target.getAdapterPosition();
Collections.swap(itemsList, fromPos, toPos);
adapter.notifyItemMoved(fromPos, toPos);
return true;
}
public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) {
adapter.onItemDismiss(viewHolder.getAdapterPosition());
}
});
itemTouchHelper.attachToRecyclerView(mRecyclerView);
} // End of onCreate
} // End of MainActivity
我的回收器适配器
import android.app.Activity;
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.helper.ItemTouchHelper;
import android.text.Editable;
import android.text.InputType;
import android.text.TextWatcher;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.view.LayoutInflater;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.RelativeLayout;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class MyRecyclerAdapter extends RecyclerView.Adapter<MyRecyclerAdapter.CustomRowViewHolder> {
private ArrayList<ListItems> itemsList;
private Context mContext;
private List<String> courseStrings;
private List<String> creditStrings;
public MyRecyclerAdapter(Context context, ArrayList<ListItems> itemsList, List<String> courseStrings, List<String> creditStrings){
this.itemsList = itemsList;
this.mContext = context;
this.courseStrings = courseStrings;
this.creditStrings = creditStrings;
}
@Override
public MyRecyclerAdapter.CustomRowViewHolder onCreateViewHolder(final ViewGroup viewGroup, int position) {
View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.new_course_row, null);
final CustomRowViewHolder holder = new CustomRowViewHolder(v, new CoursesCustomTextListener(), new CreditsCustomTextListener());
holder.creditsText.setInputType(InputType.TYPE_CLASS_NUMBER);
holder.checkBox.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(holder.checkBox.isChecked()) {
holder.courseText.setEnabled(false);
holder.courseText.setFocusable(false);
holder.courseText.setInputType(InputType.TYPE_NULL);
holder.creditsText.setEnabled(false);
holder.creditsText.setFocusable(false);
holder.creditsText.setInputType(InputType.TYPE_NULL);
} else {
holder.courseText.setEnabled(true);
holder.courseText.setFocusable(true);
holder.courseText.setFocusableInTouchMode(true);
holder.courseText.setInputType(InputType.TYPE_CLASS_TEXT);
holder.creditsText.setEnabled(true);
holder.creditsText.setFocusable(true);
holder.creditsText.setFocusableInTouchMode(true);
holder.creditsText.setInputType(InputType.TYPE_CLASS_NUMBER);
} // End if else
}
});
return holder;
} // End of onCreateViewHolder
@Override
public void onBindViewHolder(CustomRowViewHolder holder, final int position) {
ListItems listItem = itemsList.get(position);
int focusedItem = 0;
holder.itemView.setSelected(focusedItem == position);
holder.getLayoutPosition();
holder.creditsCustomTextListener.updatePosition(position);
holder.creditsCustomTextListener.updatePosition(position);
holder.courseText.setText(courseStrings.get(position));
holder.creditsText.setText(creditStrings.get(position));
// Set listener to check box.
holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
itemsList.get(position).setIsComplete(b);
}
});
holder.checkBox.setChecked( itemsList.get(position).getIsComplete());
} // End of onBindViewHolder
public void clearAdapter() {
itemsList.clear();
notifyDataSetChanged();
} // End of clearAdapter
public int getItemCount() {
return(null != itemsList ? itemsList.size() : 0);
} // End of getItemCount
public void onItemDismiss(int position) {
itemsList.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, itemsList.size());
} // End of onItemDismiss
public void createListItem(ListItems listItem, Toast toast) {
itemsList.add(listItem);
int position = itemsList.indexOf(listItem);
notifyItemInserted(position);
} // End of createListItem
///////////////////////////////////// CustomRowViewHolder /////////////////////////////////////
public static class CustomRowViewHolder extends RecyclerView.ViewHolder {
public EditText courseText;
public EditText creditsText;
public CheckBox checkBox;
public RelativeLayout relativeLayout;
public CoursesCustomTextListener coursesCustomTextListener;
public CreditsCustomTextListener creditsCustomTextListener;
public CustomRowViewHolder(View view, CoursesCustomTextListener coursesCustomTextListener, CreditsCustomTextListener creditsCustomTextListener) {
super(view);
this.coursesCustomTextListener = coursesCustomTextListener;
this.creditsCustomTextListener = creditsCustomTextListener;
this.courseText = (EditText) view.findViewById(R.id.course);
this.creditsText = (EditText) view.findViewById(R.id.credits);
this.checkBox = (CheckBox) view.findViewById(R.id.complete);
this.relativeLayout = (RelativeLayout) view.findViewById(R.id.relLayout);
this.courseText.addTextChangedListener(coursesCustomTextListener);
this.creditsText.addTextChangedListener(creditsCustomTextListener);
}
}
////////////////////////////////// CoursesCustomTextListener //////////////////////////////////
private class CoursesCustomTextListener implements TextWatcher {
private int position;
public void updatePosition(int position) {
this.position = position;
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// No operation to perform.
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
courseStrings.add(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
// No operation to perform.
}
}
////////////////////////////////// CreditsCustomTextListener //////////////////////////////////
private class CreditsCustomTextListener implements TextWatcher {
private int position;
public void updatePosition(int position) {
this.position = position;
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// No operation to perform.
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
creditStrings.add(s.toString());
}
@Override
public void afterTextChanged(Editable s) {
// No operation to perform.
}
}
} // End of MyRecyclerAdapter
列表项
import java.util.ArrayList;
public class ListItems {
private String course;
private String credits;
private Boolean complete;
public ListItems(String mCourse, String mCredits, Boolean mComplete) {
course = mCourse;
credits = mCredits;
complete = mComplete;
}
public String getCourse() {
return course;
}
public void setCourse(String course) {
this.course = course;
}
public String getCredits() {
return credits;
}
public void setCredits(String credits) {
this.credits = credits;
}
public Boolean getIsComplete() {
return complete;
}
public void setIsComplete(Boolean complete) {
this.complete = complete;
}
} // End of ListItems
new_course_row.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/relLayout"
android:layout_margin="5dp">
<EditText
android:layout_width="130dp"
android:layout_height="wrap_content"
android:id="@+id/course"
android:hint="Enter Course ID"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:textSize="16sp"
android:maxLines="1" />
<EditText
android:layout_width="115dp"
android:layout_height="wrap_content"
android:id="@+id/credits"
android:hint="Enter Credits"
android:layout_alignBottom="@+id/course"
android:textSize="16sp"
android:layout_toRightOf="@+id/course"
android:maxLines="1" />
<CheckBox
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="Check if complete"
android:id="@+id/complete"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_alignBottom="@+id/course"
android:textSize="13sp"
android:paddingBottom="4dp"
android:paddingTop="4dp" />
</RelativeLayout>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingRight="10dp"
android:paddingLeft="10dp"
android:paddingTop="10dp"
android:paddingBottom="10dp"
android:id="@+id/rl"
tools:context=".MainActivity" >
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add Course"
android:id="@+id/addCourse"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:textColor="#FFF"
android:background="@drawable/my_button"
android:textSize="18dp"
android:paddingRight="5dp"
android:paddingLeft="5dp"
android:paddingTop="15dp"
android:paddingBottom="15dp"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Clear All"
android:id="@+id/clearAll"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true"
android:textColor="#FFF"
android:background="@drawable/my_button"
android:textSize="18dp"
android:paddingRight="5dp"
android:paddingLeft="5dp"
android:paddingTop="15dp"
android:paddingBottom="15dp"/>
<android.support.v7.widget.RecyclerView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/recycler_view"
android:layout_below="@+id/addCourse"
android:layout_marginTop="10dp"
/>
</RelativeLayout>
提前感谢您的帮助!我真的可以使用解决方案!
编辑:我现在注意到，假设我在第一个 EditText 中输入“aaaaaaa”，然后它会将“a”添加到列表下方的 EditText，然后将“aa”添加到那个之后的 EditText，然后“aaa”、“aaaa”，直到到达“aaaaaaa”。然后会有一些空的EditText，然后它会重新开始。这是视觉效果:
EDIT x2:有一段时间没有研究这个，也没有得到任何答案。甚至因为这篇文章获得了“风滚草”徽章!有人有什么想法吗？
最佳答案
虽然我不太确定，但我相信这是正在发生的，因为回收器 View 重新生成了它的位置。对于您的自定义编辑文本，您要添加字符串`@Override public void onTextChanged(CharSequence s, int start, int before, int count) { courseStrings.add(s.toString());
对于两个编辑文本。 在回收站 View 中，您已经实现了 this.courseText.addTextChangedListener(coursesCustomTextListener);
所以每次滚动时都会调用 onBind 方法，并且随着位置的变化，它也必须被调用。因此它一定是再生的。我请你先试试
holder.courseText.setTag(position);
在 onBindViewHolder() 中。 分别尝试两种文本。如果它确实有效，请尝试
holder.view.setTag(position);
关于java - 在 RecyclerView 中滚动后 EditText 丢失内容，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37779059/