android – 如何使用复选框和自定义适配器从列表视图中获取选定的列表项?

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我有一个ListView与CheckBox在它.我正在使用自定义适配器来填充ListView.

在我的xml文件中,我的底部有一个Button.我想要的是让用户选择ListView中的行数,并且当他/她点击Button获取所选项目的位置,以便我可以获取特定行的对象进行进一步的计算.

解决方法

Snippet下方完全符合您的要求.
package com.windrealm.android;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class PlanetsActivity extends Activity
{

    private ListView mainListView;
    private Planet[] planets;
    private ArrayAdapter<Planet> listAdapter;
    private Button check;
    private Context context;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        context = PlanetsActivity.this;
        check = (Button) findViewById(R.id.check);
        // Find the ListView resource.
        mainListView = (ListView) findViewById(R.id.mainListView);

        // When item is tapped,toggle checked properties of CheckBox and
        // Planet.
        mainListView
                .setOnItemClickListener(new AdapterView.OnItemClickListener()
                {
                    @Override
                    public void onItemClick(AdapterView<?> parent,View item,int position,long id)
                    {
                        Planet planet = listAdapter.getItem(position);
                        planet.toggleChecked();
                        PlanetViewHolder viewHolder = (PlanetViewHolder) item
                                .getTag();
                        viewHolder.getCheckBox().setChecked(planet.isChecked());
                    }
                });

        // Create and populate planets.
        planets = (Planet[]) getLastNonConfigurationInstance();
        if (planets == null)
        {
            planets = new Planet[]
            { new Planet("Mercury"),new Planet("Venus"),new Planet("Earth"),new Planet("Mars"),new Planet("Jupiter"),new Planet("Saturn"),new Planet("Uranus"),new Planet("Neptune"),new Planet("Ceres"),new Planet("Pluto"),new Planet("Haumea"),new Planet("Makemake"),new Planet("Eris") };
        }
        ArrayList<Planet> planetList = new ArrayList<Planet>();
        planetList.addAll(Arrays.asList(planets));

        // Set our custom array adapter as the ListView's adapter.
        listAdapter = new PlanetArrayAdapter(this,planetList);
        mainListView.setAdapter(listAdapter);

        check.setOnClickListener(new OnClickListener()
        {

            @Override
            public void onClick(View view)
            {
                for (int i = 0; i < listAdapter.getCount(); i++)
                {
                    Planet planet = listAdapter.getItem(i);
                    if (planet.isChecked())
                    {
                        Toast.makeText(context,planet.getName() + " is Checked!!",Toast.LENGTH_SHORT).show();
                    }
                }

            }
        });
    }

    /** Holds planet data. */
    private static class Planet
    {
        private String name = "";
        private boolean checked = false;

        public Planet()
        {
        }

        public Planet(String name)
        {
            this.name = name;
        }

        public Planet(String name,boolean checked)
        {
            this.name = name;
            this.checked = checked;
        }

        public String getName()
        {
            return name;
        }

        public void setName(String name)
        {
            this.name = name;
        }

        public boolean isChecked()
        {
            return checked;
        }

        public void setChecked(boolean checked)
        {
            this.checked = checked;
        }

        public String toString()
        {
            return name;
        }

        public void toggleChecked()
        {
            checked = !checked;
        }
    }

    /** Holds child views for one row. */
    private static class PlanetViewHolder
    {
        private CheckBox checkBox;
        private TextView textView;

        public PlanetViewHolder()
        {
        }

        public PlanetViewHolder(TextView textView,CheckBox checkBox)
        {
            this.checkBox = checkBox;
            this.textView = textView;
        }

        public CheckBox getCheckBox()
        {
            return checkBox;
        }

        public void setCheckBox(CheckBox checkBox)
        {
            this.checkBox = checkBox;
        }

        public TextView getTextView()
        {
            return textView;
        }

        public void setTextView(TextView textView)
        {
            this.textView = textView;
        }
    }

    /** Custom adapter for displaying an array of Planet objects. */
    private static class PlanetArrayAdapter extends ArrayAdapter<Planet>
    {

        private LayoutInflater inflater;

        public PlanetArrayAdapter(Context context,List<Planet> planetList)
        {
            super(context,R.layout.simplerow,R.id.rowTextView,planetList);
            // Cache the LayoutInflate to avoid asking for a new one each time.
            inflater = LayoutInflater.from(context);
        }

        @Override
        public View getView(int position,View convertView,ViewGroup parent)
        {
            // Planet to display
            Planet planet = (Planet) this.getItem(position);

            // The child views in each row.
            CheckBox checkBox;
            TextView textView;

            // Create a new row view
            if (convertView == null)
            {
                convertView = inflater.inflate(R.layout.simplerow,null);

                // Find the child views.
                textView = (TextView) convertView
                        .findViewById(R.id.rowTextView);
                checkBox = (CheckBox) convertView.findViewById(R.id.CheckBox01);

                // Optimization: Tag the row with it's child views,so we don't
                // have to
                // call findViewById() later when we reuse the row.
                convertView.setTag(new PlanetViewHolder(textView,checkBox));

                // If CheckBox is toggled,update the planet it is tagged with.
                checkBox.setOnClickListener(new View.OnClickListener()
                {
                    public void onClick(View v)
                    {
                        CheckBox cb = (CheckBox) v;
                        Planet planet = (Planet) cb.getTag();
                        planet.setChecked(cb.isChecked());
                    }
                });
            }
            // Reuse existing row view
            else
            {
                // Because we use a ViewHolder,we avoid having to call
                // findViewById().
                PlanetViewHolder viewHolder = (PlanetViewHolder) convertView
                        .getTag();
                checkBox = viewHolder.getCheckBox();
                textView = viewHolder.getTextView();
            }

            // Tag the CheckBox with the Planet it is displaying,so that we can
            // access the planet in onClick() when the CheckBox is toggled.
            checkBox.setTag(planet);

            // Display planet data
            checkBox.setChecked(planet.isChecked());
            textView.setText(planet.getName());

            return convertView;
        }

    }

    public Object onRetainNonConfigurationInstance()
    {
        return planets;
    }
}
原文链接:https://www.f2er.com/android/311960.html

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