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android - How do I link a checkbox for every contact in populated listview?

I've been having a lot of trouble with this problem. I have a listview that contains:

ImageView / contactName / TextView / CheckBox

The contactName in the listview is populated by reading the contacts on the phone from a SimpleCursorAdapter. All for elements show when the app runs, but the problem I'm having is connecting the checkboxes to their corresponding item in the list.

Through some research, I found that I must use a getView() to link the checkboxes with the items in the list, but through practice, I can't seem to get it to work right. Furthermore, none of the examples I've tried really explained how to apply getView(). The most full example I've been working from is from here:

http://androidcocktail.blogspot.com/2012/04/adding-checkboxes-to-custom-listview-in.html

The twist is that this reads and populates my listview with my contacts:

private void populateContactList() {
    // Build adapter with contact entries
    Cursor cursor = getContacts();
    String[] fields = new String[] {
            ContactsContract.Data.DISPLAY_NAME       
    };

    SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.contact_entry, cursor,
            fields, new int[] {R.id.contactEntryText});    
    lv.setAdapter(adapter);        
} // END POPULATECONTACTLIST


private Cursor getContacts()
{ 
    // Run query
    Uri uri = ContactsContract.Contacts.CONTENT_URI;
    String[] projection = new String[] {
            ContactsContract.Contacts._ID,
            ContactsContract.Contacts.DISPLAY_NAME
    };
    String selection = ContactsContract.Contacts.IN_VISIBLE_GROUP + " = '" +
            (chkboxAllVisible ? "0" : "1") + "'";
    String[] selectionArgs = null;
    String sortOrder = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC";

    return managedQuery(uri, projection, selection, selectionArgs, sortOrder);
} // END GETCONTACTS 

How do I link each checkbox to the a corresponding contact items in my listview?

See Question&Answers more detail:os

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1 Answer

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by (71.8m points)

Ok i have created a test project for you try to understand code if any problem you are having then ask I will try to help you...

HERE IS MY ONCREATE FUNCTION OF ACTIVITY.

super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ArrayList<String> elements = new ArrayList<String>();
for (int i = 0; i < 10; i++) {
    elements.add("elements " + i);
}

CheckBox master_cb = new CheckBox(getApplicationContext());
master_cb.setText("Check All");
//HERE IS THE LIST VIEW WHICH I HAVE CREATED IN MY XML FILE.
ListView lv = (ListView) findViewById(R.id.listView1);
//HERE I AM CREATING CUSTOM ADAPTER OBJECT.
my_custom_adapter adapter = new my_custom_adapter(this, android.R.layout.simple_list_item_1, elements);
lv.addHeaderView(master_cb);
lv.setAdapter(adapter);
master_cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
        Intent my_intent = new Intent("master_check_change");
        my_intent.putExtra("check_value", isChecked);
        sendBroadcast(my_intent);
    }
});

}

HERE IS MY CUSTOM ADAPTER.

public class my_custom_adapter extends ArrayAdapter<String> {
    private Context context                     = null;
    ArrayList<String>  elements                 = null;
    private ArrayList<Boolean> itemChecked      = null;

    public my_custom_adapter(Context context, int type, ArrayList<String>  elements)
    {
        super(context, type, elements);
        this.elements =  elements;
        this.context = context;
        itemChecked = new ArrayList<Boolean>();
        BroadcastReceiver receiver = new BroadcastReceiver() {
            @Override
            public void onReceive(Context context, Intent intent) {
                if (intent.getAction().equals("master_check_change")) {
                    boolean check_value = intent.getBooleanExtra("check_value", false);
                    set_checked(check_value);
                    notifyDataSetChanged();
                }
            }
        };
        context.registerReceiver(receiver, new IntentFilter("master_check_change"));
        set_checked(false);
    }

    // AS EVERY TIME LISTVIEW INFLATE YOUR VIEWS WHEN YOU MOVE THEM SO YOU NEED TO SAVE ALL OF YOUR CHECKBOX STATES IN SOME ARRAYLIST OTHERWISE IT WILL SET ANY DEFAULT VALUE.
    private void set_checked(boolean is_checked)
    {
        for (int i=0; i < elements.size(); i++) {
            itemChecked.add(i, is_checked);
        }
    }

    //THIS IS SIMPLY A CLASS VIEW WILL HOLD DIFFERENT VIEWS OF YOUR ROW.
    static class ViewHolder
    {
        public TextView tv;
        public CheckBox cb;
        public ImageView iv;
    }

    @Override
    public View getView (final int position, View convertView, ViewGroup parent)
    {
        View rowView = convertView;
        ViewHolder holder = null;

        if (rowView == null) {
            LayoutInflater inflater = (LayoutInflater)context.getSystemService(
                                               Context.LAYOUT_INFLATER_SERVICE);
            // HERE I AM INFLATING LISTVIEW LAYOUT.
            rowView = inflater.inflate(R.layout.inflated_layout, null, false);
            holder = new ViewHolder();
            holder.cb = (CheckBox) rowView.findViewById(R.id.checkBox1);
            holder.tv = (TextView) rowView.findViewById(R.id.textView1);
            holder.iv = (ImageView) rowView.findViewById(R.id.imageView1);
            rowView.setTag(holder);

        } else {
            holder = (ViewHolder) rowView.getTag();
        }

        if (holder != null) {
            holder.tv.setText(elements.get(position));

            holder.cb.setOnCheckedChangeListener(new OnCheckedChangeListener() {

                @Override
                public void onCheckedChanged(CompoundButton buttonView,
                                             boolean isChecked) {
                    itemChecked.set(position, isChecked);
                }
            });

            if(position < itemChecked.size()) {
                holder.cb.setChecked(itemChecked.get(position));
            }
        }
        return rowView;
    }
}

main.xml file is this:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >


    <ListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true" >

    </ListView>

</RelativeLayout>

inflated_layout code is :

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <CheckBox
        android:id="@+id/checkBox1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="17dp" />




    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_toLeftOf="@+id/checkBox1"
        android:layout_toRightOf="@+id/imageView1"
        android:singleLine="true"
        android:text="Large Text"
        android:textAppearance="?android:attr/textAppearanceLarge" />


    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:src="@drawable/ic_launcher" />

</RelativeLayout>

if you want to use string array instead of arraylist then replace

    String[] elements = new String[10];
    for (int i = 0; i < 10; i++) {
        elements[i] = "elements " + i;
    }

// IN YOUR CUSTOM ADAPTER CUNSTRUCTOR

public my_custom_adapter(Context context, int type, String[]  elements)

and some more changes accordingly


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