在可扩展的 ListView 中从子项获取值

Question

我有一个 Expandable ListView(EXLV)，它的每个子项都有一个 EditText，并且在 EXLV 之外有一个 Button。我已经搞砸了一个星期。 我想在单击按钮时在 EditTexts 中输入 values/Data。 因为我输入的值会重新生成（我不知道为什么）。任何帮助将不胜感激。这是整个项目的 Link 以防万一：https://drive.google.com/file/d/1YsCb23-wL_KBgj2braqT59mPezRhSS28/view?usp=sharing

MainActiviy.java:

package com.lvexpandable;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import java.util.logging.Handler;

import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AlertDialog;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.ExpandableListView.OnGroupClickListener;
import android.widget.ExpandableListView.OnGroupCollapseListener;
import android.widget.ExpandableListView.OnGroupExpandListener;
import android.widget.Toast;

public class MainActivity extends Activity {
    final int snnn=1857;

    Button btn;
    EditText edt;
    ExpandableListAdapter listAdapter;
    ExpandableListView expListView;
    List<String> listDataHeader;
    HashMap<String, List<String>> listDataChild;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        String[] mStrings = new String[20];

        // get the listview
        expListView = (ExpandableListView) findViewById(R.id.lvExp);

        // preparing list data
        prepareListData();

        listAdapter = new ExpandableListAdapter(this, listDataHeader, listDataChild);

        // setting list adapter
        expListView.setAdapter(listAdapter);


    }
    public void btnClick(View v){
        //I want to get values entered in EditTexts here. Maybe using SharedPref, in a List<> or whatever.

    }

    /*
     * Preparing the list data
     */
    private void prepareListData() {
        listDataHeader = new ArrayList<>();
        listDataChild = new HashMap<>();

        // Adding child data
        listDataHeader.add("PG");
        listDataHeader.add("Nursery");



        // Adding child data
        List<String> pg = new ArrayList<String>();
        pg.add("PG1: ");
        pg.add("PG2: ");
        pg.add("PG3: ");
        pg.add("PG4: ");
        pg.add("PG5: ");
        pg.add("PG6: ");
        pg.add("PG7: ");
        pg.add("PG8: ");
        pg.add("PG9: ");
        pg.add("PG10: ");
        pg.add("PG11: ");
        pg.add("PG12: ");
        pg.add("PG13: ");
        pg.add("PG14: ");
        pg.add("PG15: ");


        List<String> nur = new ArrayList<String>();
        nur.add("Object A ");
        nur.add("Obj B: ");
        nur.add("Obj C:");



        listDataChild.put(listDataHeader.get(0), pg); // Header, Child data
        listDataChild.put(listDataHeader.get(1), nur);

    }
}

ExpandableListAdapter.java:

package com.lvexpandable;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Random;

import android.content.Context;
import android.content.SharedPreferences;
import android.graphics.Typeface;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class ExpandableListAdapter extends BaseExpandableListAdapter {


    private Context _context;
    private List<String> _listDataHeader; // header titles
    // child data in format of header title, child title
    private HashMap<String, List<String>> _listDataChild;






    public ExpandableListAdapter(Context context, List<String> listDataHeader,
                                 HashMap<String, List<String>> listChildData) {
        this._context = context;
        this._listDataHeader = listDataHeader;
        this._listDataChild = listChildData;

    }


    @Override
    public Object getChild(int groupPosition, int childPosititon) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .get(childPosititon);
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }



    @Override
    public View getChildView(int groupPosition, final int childPosition,
                             boolean isLastChild, View convertView, ViewGroup parent) {



        final String childText = (String) getChild(groupPosition, childPosition);

        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_item, null);
        }
        TextView txtListChild = convertView.findViewById(R.id.lblListItem);



        txtListChild.setText(childText);
        return convertView;
    }





    @Override
    public int getChildrenCount(int groupPosition) {
        return this._listDataChild.get(this._listDataHeader.get(groupPosition))
                .size();
    }

    @Override
    public Object getGroup(int groupPosition) {
        return this._listDataHeader.get(groupPosition);
    }

    @Override
    public int getGroupCount() {
        return this._listDataHeader.size();
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded,
                             View convertView, ViewGroup parent) {
        String headerTitle = (String) getGroup(groupPosition);
        if (convertView == null) {
            LayoutInflater infalInflater = (LayoutInflater) this._context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = infalInflater.inflate(R.layout.list_group, null);
        }

        TextView lblListHeader = (TextView) convertView
                .findViewById(R.id.lblListHeader);
        lblListHeader.setTypeface(null, Typeface.BOLD);
        lblListHeader.setText(headerTitle);

        return convertView;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }
}

activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.lvexpandable.MainActivity">

    <LinearLayout
        android:id="@+id/linearLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="50dp"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <ExpandableListView
            android:id="@+id/lvExp"
            android:layout_width="match_parent"
            android:layout_height="400dp" />

        <Button
            android:onClick="btnClick"
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginStart="230dp"
            android:text="Button"
            tools:layout_editor_absoluteX="257dp"
            tools:layout_editor_absoluteY="360dp" />
    </LinearLayout>



</android.support.constraint.ConstraintLayout>

如果有人有任何困惑，请随时提问:)

Answer 1

您尝试做的事情当然是可能的，但是很复杂：

在每个 Child 项中添加一个按钮
当用户输入 Child 0 时，他必须按下 Child 的按钮（单击按钮时，将值保存在索引 [childPosition] 的数组中）。在这样，Array[0] 将具有 Child 1 的文本，与 Next 类似 Child仁。

(第 3 步和其他步骤是可选的)

如果您不喜欢这种设计（因为用户每次输入值时都需要按下按钮，请参阅第 4 步）
将按钮（在步骤 1 中添加）的可见性设置为 INVISIBLE

为 ChildItem 中的 EditText 添加一个 TextWatcher (TextChangedListener)（它将获取输入的文本 > 将其保存在数组 [] 中 > 在用户离开当前 EditText 后立即单击按钮本身).如：

edt.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {}

    @Override
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {}
@Override
public void afterTextChanged(Editable editable) {

if(edt.getText().toString()==""&&edt.getText().toString().equals(null)){
}
else {
    edt.setOnFocusChangeListener(new View.OnFocusChangeListener() {
        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (!hasFocus)//Perform Click when edt loses Focus {
                btn.callOnClick();
            }
        }
    });
}
}});

现在按钮点击将如下所示：

btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
        if(edt.getText().toString().equals("")){

        }
        else {
        Toast.makeText(view.getContext(),"Entered: "+edt.getText().toString(),Toast.LENGTH_SHORT).show();
        myStringArray[childPosition]=edt.getText().toString();
        edt.setText("");
        }
    }
});

在可扩展的 ListView 中从子项获取值

Get Values from Child in Expandable ListView

java

android

expandablelistview

expandablelistadapter