Question

我正在使用一个简单的适配器来显示列表，但是在滚动listview时，switch会改变它的状态：

  lv = (ListView) findViewById(R.id.listView);
    String[] from = {"CompanyName", "AppointmenTime", "Status"};
    // view id's to which data to be binded
    int[] to = {R.id.clientname, R.id.time, R.id.togglebtn};

    //Creating Adapter
    android.widget.SimpleAdapter k = new android.widget.SimpleAdapter(ClientListActivity.this, clientData, R.layout.client_list, from, to) {
        public View getView(int position, View convertView, ViewGroup parent) {

    View v = super.getView(position, convertView, parent);
            Switch switchcompact=(Switch) v.findViewById(R.id.togglebtn);
            switchcompact.setTag(position);

       switchcompact.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                    @Override
                    public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
                        {
 ////some code
    }}

Answer 1

如果您正在滚动，那么如果列表项不可见，则会创建并销毁它们。所以你必须保存Switch的状态：

private Map<Integer, Boolean> states = new Hashmap<>();

public View getView(final int position, View convertView, ViewGroup parent) {
    View v = super.getView(position, convertView, parent);
    Switch switchcompact = (Switch) v.findViewById(R.id.togglebtn);
    switchcompact.setChecked(Boolean.TRUE.equals(states.get(position));
    switchcompact.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
            states.put(position, isChecked);
        }
    });
}

但是，这只是伪代码。我强烈建议您使用SharedPreferences保存并获取选择状态。

Answer 2

在切换状态改变后，您必须更新ArrayList（或提供给listview的数据集）中特定Item的值。

import android.content.Context;

import android.view.LayoutInflater;

导入android.view.View;

import android.view.ViewGroup;

import android.widget.BaseAdapter;

import android.widget.Switch;

import java.util.List;

import java.util.Map;

public class SimpleListViewAdaptor扩展了BaseAdapter {

Context context;
List<Map<String, Object>> data;
public SimpleListViewAdaptor(Context context, List<Map<String, Object>> data) {
    super();
    this.context=context;
    this.data=data;

}

@Override
public Map<String,Object> getItem(int position) {
    return data.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public int getCount() {
    return data.size();
}

@Override
public View getView(final int position, View convertView, ViewGroup parent) {
      HolderView holderView;
    if (convertView == null) {
        LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = mInflater.inflate(R.layout.customr_item_list,parent, false);
        holderView = new HolderView();
        holderView.aSwitch = (Switch) convertView.findViewById(R.id.togglebtn);
        convertView.setTag(holderView);
    } else {
        // View recycled !
        // no need to inflate
        // no need to findViews by id
        holderView = (HolderView) convertView.getTag();
    }

        holderView.aSwitch.setChecked((Boolean)data.get(position).get("Status"));
    holderView.aSwitch.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(final View v) {
            if(((Switch)v).isChecked()){
                ((Switch)v).setChecked(true);
                data.get(position).put("Status",true);//this is imp to update the value in dataset which is provided to listview

            }else{
                ((Switch)v).setChecked(false);
                data.get(position).put("Status",false);

            }
        }
    });
    return convertView;
}

static class HolderView{
    Switch aSwitch;
}

}

我正在使用Simple Adapter for listview但是在listview中滚动更改其状态？

2 个答案: