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java - 如何选中/取消选中 ExpandableListView 中的 CheckedTextView（子项）项？

问题描述

我的设计： 我为我的 ExpandableListView 创建了一个自定义适配器（SignalsExpandableListAdapter)带有 CheckedTextView。

public class SignalsExpandableListAdapter extends BaseExpandableListAdapter {
private Context context;
private List<String> listDataHandler;
private HashMap<String,List<String>> listHashMap;

public SignalsExpandableListAdapter(Context context, List<String> listDataHandler, HashMap<String, List<String>> listHashMap) {
    this.context = context;
    this.listDataHandler = listDataHandler;
    this.listHashMap = listHashMap;
}

然后将数据填充到一个片段中，如下所示。这很好用。我可以在我的 ExpandableListView 中看到子元素和父元素。

ArrayList<List<String[]>> deviceMList = new ArrayList<>();
final List<String[]> mList = new ArrayList<>();
deviceMList.add(mList);

我在找什么我：当我选择任何孩子（可以是多个）时，我想使用 CheckedTextView 用勾号表示该选择。当我选择任何选中的子项目时，我也想取消选中。（一个简单的检查/取消检查设计）。As well when any child is selected another function is called for plotting. 这就是我卡住的地方。每次当我选择一个孩子时，随机多个孩子 checkTextViews 也被指示为选中，而不仅仅是我选择的那个。

经过一番搜索，我尝试了 3 次尝试来克服这个问题并只检查我选择的孩子。但似乎我的任何尝试都没有奏效。我不确定发生了什么。我的尝试如下所述。我真的很感激对此的任何建议。

我尝试了尝试 4（在下面的第 II 节中描述），但似乎仍然没有实时进行检查/取消检查。

尝试 1：试图在 Fragment 中使检查为真

listAdapter = new SignalsExpandableListAdapter(context,signalsListDataHeader,signalsListHash);
signalsExpandableListView.setAdapter(listAdapter);
signalsExpandableListView.setChoiceMode(AbsListView.CHOICE_MODE_MULTIPLE);
//tickCheckboxes();

signalsExpandableListView.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
    @Override
    public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) {
        CheckedTextView sensorCheckedView  = (CheckedTextView) v.findViewById(R.id.sensorsCheckedTextView);
        if(!mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))) {
            sensorCheckedView.setChecked(true);
            try {
                if(Plot==null) {
                    Log.e(LOG_TAG, "Plot is null!");
                }
                mService.mPlotManager.addSignal(deviceMList.get(groupPosition).get(childPosition), Plot);
            } catch (Exception e) {
                Log.e(LOG_TAG, "Error! + e);
                e.printStackTrace();
            }
        } else {
            mService.mPlotManager.removeSignal(deviceMList.get(groupPosition).get(childPosition));
            //signalsExpandableListView.setItemChecked(childPosition,false);
            sensorCheckedView.setChecked(false);
        }
        return true;
    }
});

尝试 2：创建一个不同的函数并在 Fragment 中调用它。创建的函数如下，函数调用在尝试 1 上方注释。

//loop through groups and then children
public void tickCheckboxes() {
    //CheckedTextView sensorCheckedView  = (CheckedTextView) signalsExpandableListView.findViewById(R.id.sensorsCheckedTextView);
    for (int i = 0; i < deviceMList.size(); i++) {
        for (int j = 0; j < deviceMList.get(i).size(); j++) {
            if (mService.mPlotManager.ifPropertyExist(deviceMList.get(i).get(j))) {
                signalsExpandableListView.setItemChecked(j, true);
                //sensorCheckedView.setChecked(true);
            } else {
                signalsExpandableListView.setItemChecked(j, false);
                //sensorCheckedView.setChecked(false);
            }
        }
    }
}

尝试 3：使用 ExpandableListView 适配器访问子元素。我更新了getChildView()方法如下。

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) {
    final String childText = (String) getChild(groupPosition,childPosition);
    if(view == null){
        LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.sensors_list_items,null);
    }
    CheckedTextView txtListChild = (CheckedTextView) view.findViewById((R.id.sensorsCheckedTextView));
    txtListChild.setText(childText);
    txtListChild.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (txtListChild.isChecked()) {
                txtListChild.setChecked(false);
            } else {
                txtListChild.setChecked(true);
            }
        }
    });
    return view;
}

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

列出项目 xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <CheckedTextView
        android:id="@+id/sensorsCheckedTextView"
        android:layout_width="match_parent"
        android:layout_height="?android:attr/listPreferredItemHeightSmall"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:gravity="center_vertical"
        android:checkMark="?android:attr/listChoiceIndicatorMultiple"
        android:paddingLeft="?android:attr/expandableListPreferredChildPaddingLeft"
        android:textColor="@color/black"
        android:paddingTop="5dp"
        android:paddingBottom="5dp"/>


</LinearLayout>

组 xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:id="@+id/deviceNameTextView"
        android:layout_width="match_parent"
        android:layout_height="?android:attr/listPreferredItemHeightSmall"
        android:textAppearance="?android:attr/textAppearanceListItemSmall"
        android:gravity="center_vertical"
        android:text="Device Name"
        android:paddingTop="5dp"
        android:paddingBottom="5dp"
        android:background="@color/colorAccent"
        android:textColor="@color/colorPrimary"
        android:paddingLeft="?android:attr/expandableListPreferredItemPaddingLeft"/>
</LinearLayout>

我在寻找什么 II：对于检查/取消检查，我在下面提到的答案的帮助下修改了适配器，如尝试 4中所示。我无法checked实时看到标记。当我单击一个孩子时，我想向上/向下滚动以直观地看到复选标记。与取消选中相同。它很奇怪。似乎需要一种“刷新”才能实时查看选中/取消选中状态。我将不胜感激有关如何摆脱这种情况的任何建议。

谢谢你。

尝试 4：修改适配器。这适用于选中/取消选中，但无法实时直观地看到它。

public class SignalsExpandableListAdapter extends BaseExpandableListAdapter {
    private Context context;
    private List<String> listDataHandler;
    private HashMap<String,List<String>> listHashMap;
    private MService mService;
    private ArrayList<List<String[]>> deviceMList ;

    public SignalsExpandableListAdapter(Context context, List<String> listDataHandler, HashMap<String, List<String>> listHashMap,mService service, ArrayList<List<String[]>> dMList ) {
        this.context = context;
        this.listDataHandler = listDataHandler;
        this.listHashMap = listHashMap;
        this.mService = service;
        this.deviceMList =dMList;
    }

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) {
    final String childText = (String) getChild(groupPosition,childPosition);
    if(view == null){
        LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.sensors_list_items,null);
    }
    CheckedTextView txtListChild = (CheckedTextView) view.findViewById((R.id.sensorsCheckedTextView));
    txtListChild.setText(childText);

if(mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))) {
        txtListChild.setChecked(true);
    } else {
        txtListChild.setChecked(false);
    }
    return view;
}

标签： javaandroidandroid-fragmentsexpandablelistviewcheckedtextview

解决方案

我假设您的mService带有一个名为 PlottingService 的类，然后尝试对适配器进行以下更改：

public class SignalsExpandableListAdapter extends BaseExpandableListAdapter {
    private Context context;
    private List<String> listDataHandler;
    private HashMap<String,List<String>> listHashMap;
    private PlottingService mService;

    public SignalsExpandableListAdapter(Context context, List<String> listDataHandler, HashMap<String, List<String>> listHashMap, PlottingService ps) {
        this.context = context;
        this.listDataHandler = listDataHandler;
        this.listHashMap = listHashMap;
        this.mService = ps;
    }

    @Override
    public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) {
        final String childText = (String) getChild(groupPosition,childPosition);
        if(view == null){
            LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            view = inflater.inflate(R.layout.sensors_list_items,null);
        }
        CheckedTextView txtListChild = (CheckedTextView) view.findViewById((R.id.sensorsCheckedTextView));
        txtListChild.setText(childText);

        // Always set check state according to data.
        if(mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))) {
            txtListChild.setChecked(true);
        } else {
            txtListChild.setChecked(false);
        }

        return view;
    }

在 Fragment 内部，执行 Attempt 1，只更改： listAdapter = new SignalsExpandableListAdapter(context,signalsListDataHeader,signalsListHash); 到 listAdapter = new SignalsExpandableListAdapter(context,signalsListDataHeader,signalsListHash, mService);

希望有帮助！

更新：-在 Fragment 中，注释掉 OnChildClickListener 并在适配器中，使用以下 getChildView：

public View getChildView(final int groupPosition, final int childPosition, boolean isLastChild, View view, ViewGroup parent) {
    String childText = (String) getChild(groupPosition,childPosition);
    if(view == null){
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.sensors_list_items,null);
    }
    CheckedTextView txtListChild = (CheckedTextView) view.findViewById((R.id.sensorsCheckedTextView));
    txtListChild.setText(childText);

    // Always set check state according to data.
    if(mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))) {
        txtListChild.setChecked(true);
    } else {
        txtListChild.setChecked(false);
    }

    txtListChild.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            CheckedTextView sensorCheckedView = (CheckedTextView)v;
            if(!sensorCheckedView.isChecked()) {
                sensorCheckedView.setChecked(true);
                try {
                    if(Plot==null) {
                        Log.e(LOG_TAG, "Plot is null!");
                    }
                    mService.mPlotManager.addSignal(deviceMList.get(groupPosition).get(childPosition), Plot);
                } catch (Exception e) {
                    Log.e(LOG_TAG, "Error!" + e);
                    e.printStackTrace();
                }
            } else {
                mService.mPlotManager.removeSignal(deviceMList.get(groupPosition).get(childPosition));
                sensorCheckedView.setChecked(false);
            }
        }
    });
    return view;
}

更新 2：-在 Fragment 中，注释掉 OnChildClickListener 并在适配器中，添加一个内部类并使用以下 getChildView：

class Position {
    int group, child;
    Position(int group, int child) {
        this.group = group;
        this.child = child;
    }
}

@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) {
    String childText = (String) getChild(groupPosition,childPosition);
    if(view == null){
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.sensors_list_items,null);
    }
    CheckedTextView txtListChild = (CheckedTextView) view.findViewById((R.id.sensorsCheckedTextView));
    txtListChild.setText(childText);

    // Always set check state according to data.
    if(mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))) {
        txtListChild.setChecked(true);
    } else {
        txtListChild.setChecked(false);
    }

    txtListChild.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            CheckedTextView sensorCheckedView = (CheckedTextView)v;
            int groupPosition = ((Position)v.getTag()).group;
            int childPosition = ((Position)v.getTag()).child;
            if(!sensorCheckedView.isChecked()) {
                sensorCheckedView.setChecked(true);
                try {
                    if(Plot==null) {
                        Log.e(LOG_TAG, "Plot is null!");
                    }
                    mService.mPlotManager.addSignal(deviceMList.get(groupPosition).get(childPosition), Plot);
                } catch (Exception e) {
                    Log.e(LOG_TAG, "Error!" + e);
                    e.printStackTrace();
                }
            } else {
                mService.mPlotManager.removeSignal(deviceMList.get(groupPosition).get(childPosition));
                sensorCheckedView.setChecked(false);
            }
        }
    });
    txtListChild.setTag(new Position(groupPosition, childPosition));
    return view;
}

如果Updated 2仍然存在多个checked项目的问题，那么可能的原因是mService.mPlotManager.ifPropertyExist(deviceMList.get(groupPosition).get(childPosition))。与其使用mService来验证是否选择了某个项目，不如将listHashMap从更改HashMap<String, List<String>>为HashMap<String, List<ChildItem>>[The accepted answer in Values of counter changes after scrolling ExpendableListView可能是一个更好的主意，您需要一个布尔字段而不是整数字段，数量]。然后，当单击子项时，检查并更新列表。

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