如何在自定义光标适配器中保留edittext值 [英] How to preserve edittext value in custom cursor adapter
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问题描述
将来自堆栈溢出的几乎所有答案应用于同一主题之后，但我找不到解决问题的方法. 我的问题是我有一个列表视图，其中每行包含一个问题和一个编辑文本.但是当我滚动列表视图中的数据时，编辑文本发生更改，或者可能发生在其他编辑文本中. 也就是说，如果我在滚动后在第一editext中写了一些东西，则可能发生在第二行或第三行edittext中.
After applying almost all answers from stack overflow on same topic but i can not find solution for my problem. my problem is i have a list view which contain a question and a edit text in each row. but when i scroll list view data in edit text change or it may happen it comes in other edit text. i.e if i write some thing in 1st editext after scroll it may happen it is in 2nd or 3rd row edittext.
我什至尝试了cursoradapter类中的某些东西，但仍然如此.
Some of the thing i have even tried from cursoradapter class but still.
请帮助我.
import android.content.Context;
import android.content.res.Resources;
import android.database.Cursor;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.EditText;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
public class TestViewAdapter extends CursorAdapter
{
protected Cursor cursor;
protected Context context;
protected Resources res;
protected Random random;
protected LayoutInflater inflater;
protected Map<Integer, String>myinputs;
protected int mRowIDColumn;
public TestViewAdapter(Context context, Cursor c)
{
super(context, c);
this.cursor = c;
this.context = context;
this.res = this.context.getResources();
this.random = new Random();
boolean cursorPresent = c != null;
mRowIDColumn = cursorPresent ? this.cursor.getColumnIndexOrThrow("_id") : -1;
this.inflater = (LayoutInflater) this.context.getSystemService(this.context.LAYOUT_INFLATER_SERVICE);
myinputs = new HashMap<>();
}
private static class Viewholder
{
TextView question;
TextView answer;
EditText useranswer;
String que = "" , randomStr ="";
}
@Override
public View newView(Context context, Cursor c, ViewGroup parent)
{
View rowlayout = this.inflater.inflate(R.layout.testlist_row, null);
final Viewholder viewHolder;
String [] meaningArray = new String[] {"synonyms", "antonyms"};
viewHolder = new Viewholder();
// Set view for each row
viewHolder.question = (TextView) rowlayout.findViewById(R.id.tv_test_question);
viewHolder.answer = (TextView) rowlayout.findViewById(R.id.tv_test_answer);
viewHolder.useranswer = (EditText) rowlayout.findViewById(R.id.et_test_useranswer);
viewHolder.que = this.res.getString(R.string.popup_question); //get value from string.xml
//viewHolder.randomStr = meaningArray[this.random.nextInt(meaningArray.length)];
viewHolder.useranswer.clearFocus();
rowlayout.setTag(viewHolder);
return rowlayout;
}
@Override
public int getCount() {
return cursor.getCount();
}
@Override
public long getItemId(int position) {
if (cursor != null) {
if (cursor.moveToPosition(position)) {
return cursor.getLong(mRowIDColumn);
} else {
return 0;
}
} else {
return 0;
}
}
@Override
public void bindView(View view, Context context, Cursor c)
{
final Viewholder viewHolder = (Viewholder) view.getTag();
final int rowPosition = (int) getItemId(c.getPosition());
String synonyms = "" , antonyms = "" , word = "",text = "" ,ans = "";
word = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(1)));
synonyms = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(2)));
antonyms = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(3)));
if ( !synonyms.isEmpty())
{
text = String.format(viewHolder.que, "synonyms", word.toLowerCase());
ans = synonyms;
}
else if( !antonyms.isEmpty())
{
text = String.format(viewHolder.que, "antonyms", word.toLowerCase());
ans = antonyms;
}
viewHolder.question.setText(text);
viewHolder.answer.setText(ans);
viewHolder.useranswer.addTextChangedListener(new TextWatcher() {
@Override
public void afterTextChanged(Editable s) {}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count)
{
if (s.toString().length() > 0) {
Log.d("TestViewAdapterb", "pos -" + rowPosition + "," + s.toString());
myinputs.put(rowPosition , s.toString());
}
}
});
String v = myinputs.get(rowPosition);
viewHolder.useranswer.setText(v == "" ? "" : v);
}
}
我知道了，下面是保留用户输入的更新代码. 希望对身体有帮助.
I got the way and below one is my updated code for preserving user input. hope it will be helpful to some body.
public class TestViewAdapter extends CursorAdapter
{
protected Cursor cursor;
protected Context context;
protected Resources res;
protected Random random;
protected LayoutInflater inflater;
protected ArrayList<HashMap<String,String>> resultList;
protected int mRowIDColumn;
public TestViewAdapter(Context context, Cursor c)
{
super(context, c);
this.cursor = c;
this.context = context;
this.res = this.context.getResources();
this.random = new Random();
boolean cursorPresent = c != null;
mRowIDColumn = cursorPresent ? this.cursor.getColumnIndexOrThrow("_id") : -1;
this.inflater = (LayoutInflater) this.context.getSystemService(this.context.LAYOUT_INFLATER_SERVICE);
resultList = new ArrayList<HashMap<String,String>>();
if(c != null && c.getCount() > 0)
{
c.moveToFirst();
for (int i=0;i<c.getCount();i++)
{
HashMap<String,String> row = new HashMap<String,String>();
row.put("userans","");
resultList.add(row);
}
}
}
private static class Viewholder
{
TextView question;
TextView answer;
EditText useranswer;
String randomStr ="";
}
public ArrayList<HashMap<String,String>> getUserInputResult()
{
return resultList;
}
@Override
public View newView(Context context, Cursor c, ViewGroup parent)
{
View rowlayout = this.inflater.inflate(R.layout.testlist_row, null);
final Viewholder viewHolder;
String [] meaningArray = new String[] {"synonyms", "antonyms"};
viewHolder = new Viewholder();
// Set view for each row
viewHolder.question = (TextView) rowlayout.findViewById(R.id.tv_test_question);
viewHolder.answer = (TextView) rowlayout.findViewById(R.id.tv_test_answer);
viewHolder.useranswer = (EditText) rowlayout.findViewById(R.id.et_test_useranswer);
viewHolder.randomStr = meaningArray[this.random.nextInt(meaningArray.length)];
viewHolder.useranswer.clearFocus();
rowlayout.setTag(viewHolder);
return rowlayout;
}
@Override
public int getCount() {
return cursor.getCount();
}
@Override
public long getItemId(int position) {
if (cursor != null) {
if (cursor.moveToPosition(position)) {
return cursor.getLong(mRowIDColumn);
} else {
return 0;
}
} else {
return 0;
}
}
@Override
public void bindView(View view, Context context, Cursor c)
{
final Viewholder viewHolder = (Viewholder) view.getTag();
final int rowPosition = (int) getItemId(cursor.getPosition());
final int rowId = cursor.getInt(cursor.getColumnIndex(cursor.getColumnName(0)));
boolean isBoth = false, isSyno = false , isAnto = false, isQuestionset = false;
String que = "";
String synonyms = "";
String antonyms = "";
String word = "";
String text = "";
String ans = "";
que = this.res.getString(R.string.popup_question);
word = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(1)));
synonyms = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(2)));
antonyms = cursor.getString(cursor.getColumnIndex(cursor.getColumnName(3)));
if (!synonyms.isEmpty() && !antonyms.isEmpty())
{
isBoth = true;
isSyno = true;
isAnto = true;
}
else if (!synonyms.isEmpty())
{
isSyno = true;
}
else if (!antonyms.isEmpty())
{
isAnto = true;
}
if (isBoth)
{
if(viewHolder.randomStr.equals("synonyms"))
{
text = String.format(que, "synonyms", word.toLowerCase());
ans = synonyms;
}
else
{
text = String.format(que, "antonyms", word.toLowerCase());
ans = antonyms;
}
}
else if (isSyno)
{
if (viewHolder.randomStr.equals("synonyms"))
{
text = String.format(que, "synonyms", word.toLowerCase());
ans = synonyms;
isQuestionset = true;
}
else if (isAnto)
{
text = String.format(que, "antonyms", word.toLowerCase());
ans = antonyms;
isQuestionset = true;
}
if (!isQuestionset)
{
text = String.format(que, "synonyms", word.toLowerCase());
ans = synonyms;
isQuestionset = true;
}
}
else if (isAnto)
{
text = String.format(que, "antonyms", word.toLowerCase());
ans = antonyms;
}
viewHolder.question.setText(text);
viewHolder.answer.setText(ans);
HashMap<String,String> row = resultList.get(c.getPosition());
row.put("preans",ans);
viewHolder.useranswer.setId(cursor.getPosition());
viewHolder.useranswer.setOnFocusChangeListener(new View.OnFocusChangeListener() {
@Override
public void onFocusChange(View v, boolean hasFocus)
{
if (!hasFocus)
{
if (((EditText)v).getText().toString().length() > 0) {
Log.d("TestViewAdapterb", "pos -" + rowPosition + "," + ((EditText)v).getText().toString().trim());
HashMap<String,String> row = resultList.get(v.getId());
row.put("userans",((EditText)v).getText().toString().trim());
}
}
}
});
viewHolder.useranswer.setText(row.get("userans"));
}
}
再添加一件事
android:descendantFocusability ="beforeDescendants"
android:descendantFocusability="beforeDescendants"
这将允许子视图在用户单击列表视图的项目时获得焦点.要在用户滚动列表视图时存储值，我使用了持有hashmap对象的arraylist.我了解到的第二件事是，永远不要使用'=='代替字符串，而使用isEmpty方法或contains方法.
This will allow child view to get focus when user clicks on item of the list view.To store value when user scroll the listview i have used arraylist which holds hashmap object. second thing i learned is that never comparee string using '==' in place of it use isEmpty method or contains method.
推荐答案
我想问题出在这一行:
text = String.format(viewHolder.que, "synonyms", word.toLowerCase());
我之所以说这是因为您要引用ViewHolder来获取文本的值.由于ViewHolder回收，因此文本的值也将回收.
The reason I say this is because you're referencing the ViewHolder to get the value of the text. Since the ViewHolder recycles, the value of your text will recycle too.
尝试直接从光标获取文本值，而无需ViewHolder的干预.
Try getting the value of the text directly from the cursor without intervention from the ViewHolder.
这篇关于如何在自定义光标适配器中保留edittext值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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