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Wie erhält man ausgewählte Listenelemente aus einer Listview mit checkBox und Custom Adapter?

Ich habe eine ListView mit CheckBox drauf. und ich benutze Custom Adapter, um die ListView aufzufüllen.

In meiner xml-Datei habe ich unten eine Button. Ich möchte, dass der Benutzer die Anzahl der Zeilen in ListView auswählen kann, und wenn er/sie auf Button klickt, erhalten Sie die Position der ausgewählten Elemente, damit ich das Objekt für eine bestimmte Zeile für weitere Berechnungen erhalten kann.

13
Akram

Unter dem Snippet wird genau das gemacht, was Sie möchten.

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;
    }
}
11
Vipul Shah

Tun Sie in der getview-Methode des benutzerdefinierten Adapters 

//use the actual id of your checkbox of course
Checkbox checkbox = (CheckBox)findViewById(R.id.checkbox); 
checkbox.setFocusable(false);
checkbox.setFocusableInTouchMode(false);

jetzt ist das Kontrollkästchen sowie das Listenelement anklickbar.

2
Biojayc

Ich hatte genau das gleiche Problem. Ich habe es auf diese Weise gelöst

public class myActivity extends Activity  {
//ActionBarSherlock mSherlock = ActionBarSherlock.wrap(this);
public ListView listview;
private ArrayList<Object> itemlist=new ArrayList<Object>();
Button button;
private myAdapter adapter;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    listview=(ListView)findViewById(R.id.listview1);
    button=(Button)findViewById(R.id.button1);
    /*add some data to ur list*/ itemlist.add(something);
    adapter=new Adapter(myActivity.this, 0, itemlist);
    listview.setAdapter(adapter);
    **listview.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
    listview.setItemsCanFocus(false);**
    button.setOnClickListner(new OnClickListner()
    {
     @Override
     public void OnClick(View v)
     {
      /* this returns the checked item positions in the listview*/
      **ArrayList<Integer> itempositions=adapter.getcheckeditemcount();**

    for(int i:itempositions)
    {
             /* This is the main part...u can retrieve the object in the listview which is checked and do further calculations with it*/
        **Object info=adapter.getItem(i);**
                          Log.d(TAG,"checked object info= ",info.something);
                 }
     }
    });
}


private class myAdapter extends ArrayAdapter<Object>  {

    private Context context;
    private ArrayList<Object> list;
    **private ArrayList<Integer> checkedpositions;**


    public myAdapter(Context localContext,int textViewResourceId, ArrayList<Object> objects) {
        super(localContext,textViewResourceId,objects);
        context = localContext;
        this.list=objects;
        this.checkedpositions=new  ArrayList<Integer>();
        //Log.d("adapter","list size= "+objects.size());
    }

@Override       
    public View getView(int position, View convertView, ViewGroup parent) {

        ImageView picturesView;
        View v = convertView;
        TextView Mainitem;
        final CheckBox check;

       if (v == null) 
       {
           LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
           v = vi.inflate(R.layout.albumview, null);


           Object item=list.get(position);
           if(item!=null)
           {

               check = (CheckBox)v.findViewById(R.id.checkBox1);
                   /* set a tag for chekbox with the current view position */
               **check.setTag(position);**
                   /*set a onchecked change listner for listning to state of checkbox toggle */
               check.setOnCheckedChangeListener(new OnCheckedChangeListener() 
               { 
                   @Override
                   public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) 
                   {             
                                       /*get the tag of the checkbox...in this case this will give the (position of view)*/
                       Object tag=check.getTag();
                       if ( isChecked ) 
                       { 
                           // perform logic 
                           count++;
                           Log.d("Checkbox","added "+tag);
                           checkedpositions.add((Integer) tag);
                       } 
                       else
                       {
                           count--;
                           checkedpositions.remove(tag);
                           Log.d("Checkbox","removed "+(Integer)tag);
                       }

               /* if u dont have a textview in ur listview then ignore this part */        
               Mainitem = (TextView) v.findViewById(R.id.textView1);
               Mainitem.setText(item.Album_name);

               } catch (IOException e) {
                     // TODO Auto-generated catch block
                     Log.d("error", "wall");
                 }

           }

       }

    return v;

    }
   /* Finally create a method which return the checkeditem postions in the listview */
**public ArrayList<Integer> getcheckeditemcount()
{
    return this.checkedpositions;
}**

}

}

Ich hoffe das hilft.

0
Abhiatreyas

Um dieses Problem zu lösen, müssen Sie eine benutzerdefinierte Elementklasse erstellen, die Ihre individuellen Kontrollkästchen in der Liste darstellt. Das Array dieser Elemente wird dann von der Adapterklasse verwendet, um Ihre Kontrollkästchen anzuzeigen.

Diese Item-Klasse hat eine boolesche Variable isSelected, die bestimmt, ob das Kontrollkästchen aktiviert ist oder nicht. Sie müssen den Wert dieser Variablen in Ihrer OnClick-Methode Ihrer benutzerdefinierten Adapterklasse festlegen

Zum Beispiel 

    class CheckBoxItem{

    boolean isSelected;


    public void setSelected(boolean val) {
            this.isSelected = val;
        }

        boolean isSelected(){
            return isSelected;

        }   

    }

Für Ihre CustomAdapter-Klasse, die wie folgt aussieht:

    public class ItemsAdapter extends ArrayAdapter implements OnClickListener { 

// you will have to initialize below in the constructor 
    CheckBoxItem items[];



    // You will have to create your check boxes here and set the position of your check box
    /// with help of setTag method of View as defined in below method, you will use this later // in your onClick method 

    @Override 
        public View getView(int position, View convertView, ViewGroup parent) { 
            View v = convertView; 



            CheckBox cBox = null;

            if (v == null) { 
                LayoutInflater vi = (LayoutInflater) apUI.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
                v = vi.inflate(R.layout.attachphoto, null);     

            } 



            CheckBoxItemItem it = items[position];      

            cBox =(CheckBox) v.findViewById(R.id.apCheckBox);
            cBox.setOnClickListener(this);
            cBox.setTag(""+position);       


            Log.d(TAG, "  CHECK BOX IS: "+cBox+ "   Check Box selected Value: "+cBox.isChecked()+"  Selection: "+it.isSelected());
            if(cBox != null){
                cBox.setText("");
                cBox.setChecked(it.isSelected());
            }       


            return v; 
        } 


        public void onClick(View v) {
            CheckBox cBox =(CheckBox) v.findViewById(R.id.apCheckBox);
            int position = Integer.parseInt((String) v.getTag());

            Log.d(TAG, "CLicked ..."+cBox.isChecked());

            items[position].setSelected(cBox.isChecked());              
        } 

    }

Später werden Sie ein Array Ihrer CheckBoxItem-Klasse angeben, das in Ihrer Adapter-Klasse enthalten sein wird. In diesem Fall handelt es sich um die ItemsAdapter-Klasse.

Wenn der Benutzer dann die Schaltfläche drückt, können Sie alle Elemente im Array durchlaufen und prüfen, welche ausgewählt ist, indem Sie die isSelected () - Methode der CheckBoxItem-Klasse verwenden.

In Ihrer Aktivität haben Sie:

ArrayList getSelectedItems(){

ArrayList selectedItems = new ArrayList();

int size = items.length;

        for(int i = 0; i<size; i++){
            CheckBoxItem cItem = items[i];
            if(cItem.isSelected()){                 
                selectedItems.add(cItem);                   
            }           
        }

return selectedItems;

}
0
user_CC