Get data from all rows in ListView with CustomViews

Question

Android 2.3.3, MinSDK = 8

I have a ListView, with CustomView (with an Image, two textviews and 1 checkbox) for each row. I have a button called Add Contacts. On click of this button, I have the check whether the checkbox is checked or not. If Checked, I have to get the values of the image, and two textviews and store in database.

I know how ListView's CustomView works. The views get created as and when they are displayed. So, how do I get all the rows that are checked?

Here is the XML layout :::

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="100dp"
    android:layout_margin="2dp"    
    android:orientation="horizontal" >

    <ImageView
        android:id="@+id/imgView_addcontact"
        android:layout_width="0dip"
        android:layout_height="100dp"
        android:layout_weight="0.20"
        android:padding="5dp"
        android:src="@drawable/addcontactsmall2" />

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="100dp"
        android:layout_gravity="center"
        android:layout_weight="0.60"
        android:orientation="vertical"
        android:padding="5dp" >

        <TextView
            android:id="@+id/txtView_addcontact_contactname"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Contact Name"
            android:textSize="20sp" />

        <TextView
            android:id="@+id/txtview_addcontact_phonenumber"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Phone Number"
            android:textSize="16sp" />
    </LinearLayout>

    <CheckBox
        android:id="@+id/chbk_addcontact"
        android:layout_width="0dp"
        android:layout_height="100dp"
        android:layout_weight="0.10"
        android:layout_gravity="center"
        android:padding="5dp" />

</LinearLayout>

Here is the code that i am trying - though I know, it doesn't work :::

for(int i = 0; i< lv_addcontacts.getCount(); i++)
            {
                View contactView = lv_addcontacts.getChildAt(i);

                CheckBox contactView_chbk = (CheckBox) contactView.findViewById(R.id.chbk_addcontact);
                TextView contactView_txt_contactname = (TextView) contactView.findViewById(R.id.txtView_addcontact_contactname);
                TextView contactView_txt_phonenumber = (TextView) contactView.findViewById(R.id.txtview_addcontact_phonenumber);

                if(contactView_chbk.isChecked())
                {   
                    System.out.println("Contact Name = " + contactView_txt_contactname.getText().toString());
                    System.out.println("Phone Number = " + contactView_txt_phonenumber.getText().toString());
                    System.out.println("CheckBox Status = Checked");
                    System.out.println("");
                }
                else
                {
                    System.out.println("Contact Name = " + contactView_txt_contactname.getText().toString());
                    System.out.println("Phone Number = " + contactView_txt_phonenumber.getText().toString());
                    System.out.println("CheckBox Status = Not Checked");
                    System.out.println("");
                }

            }

And the Exception I get :::

// OutPut

04-08 12:28:47.539: I/System.out(3244): Contact Name = Self Help
04-08 12:28:47.539: I/System.out(3244): Phone Number = *111#
04-08 12:28:47.539: I/System.out(3244): CheckBox Status = Not Checked
04-08 12:28:47.539: I/System.out(3244): Contact Name = Bonus Cards
04-08 12:28:47.539: I/System.out(3244): Phone Number = *444#
04-08 12:28:47.539: I/System.out(3244): CheckBox Status = Checked
04-08 12:28:47.539: I/System.out(3244): Contact Name = Annaya
04-08 12:28:47.539: I/System.out(3244): Phone Number = +1xxxx
04-08 12:28:47.539: I/System.out(3244): CheckBox Status = Not Checked

// Exception

04-08 12:28:47.539: W/dalvikvm(3244): threadid=1: thread exiting with uncaught exception (group=0x401be560)
04-08 12:28:47.539: E/AndroidRuntime(3244): FATAL EXCEPTION: main
04-08 12:28:47.539: E/AndroidRuntime(3244): java.lang.NullPointerException
04-08 12:28:47.539: E/AndroidRuntime(3244):     at com.xxx.xx.Class_Add_Contact.onClick(Class_Add_Contact.java:277)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.view.View.performClick(View.java:2485)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.view.View$PerformClick.run(View.java:9080)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.os.Handler.handleCallback(Handler.java:587)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.os.Handler.dispatchMessage(Handler.java:92)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.os.Looper.loop(Looper.java:130)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at android.app.ActivityThread.main(ActivityThread.java:3687)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at java.lang.reflect.Method.invokeNative(Native Method)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at java.lang.reflect.Method.invoke(Method.java:507)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:878)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:636)
04-08 12:28:47.539: E/AndroidRuntime(3244):     at dalvik.system.NativeStart.main(Native Method)

The exception is coming because, the views are not yet created. But, then, how do i get the checked values in the entire list.

EDIT :::

If i choose to implement onCheckedChange() for the checkbox, How do i get the ListView Item, of the current checked checkbox, inside the onCheckedChange() method?

@Override
        public void onCheckedChanged(CompoundButton buttonView,
                boolean isChecked) {
            // TODO Auto-generated method stub

            if(isChecked)
            {
                // How do I get the View(CustomView of ListView) to access the textViews and ImageView?
            }

        }

You should not depend on the views in the ListView but rather the real items in the list. I guess you get the data somewhere. Use that data instead of the ListView views data. As you mentioned those are not build yet. Actually the ListView is reusing the views so this is really unreliable. If you dont have the data of the checkboxes keep track of them in a List yourself. — QVDev, Apr 08 '13 at 07:08
@QVDev I choose to implement onCheckedChange() for the checkbox, to get the data, when the checkbox is checked, How do I get the ListView item in the onCheckedChange() of the checkbox. I have edited my question, please check it.. — Vamsi Challa, Apr 08 '13 at 07:23
I suggest you to take a Boolean arraylist for checking the checked rows of listview. Use setTag() and getTag() methods for that — krishna, Apr 08 '13 at 07:25
You can for instance when creating the checkbox assign the tag with the row number of the matching view. This way you can store the data in a new List or Map. What you prefer. But it seems the solution is to keep track of the selected checkboxes yourself. This means when you have OnCheckedChange() you can get the buttonView.tag value, that should match the current row that you assigned before — QVDev, Apr 08 '13 at 07:26
@QVDev Yeah, you are probably right. I will try some changes and get back on this. — Vamsi Challa, Apr 08 '13 at 07:29

score 1 · Accepted Answer · answered Apr 08 '13 at 07:29

Make an inner class like this with the getter setters for your values which you want to store

class CommonCategory {

        private String nameofFriend;
        private boolean isChecked;

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

        public String getName() {
            return nameofFriend;
        }

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

        public boolean isChecked() {
            return isChecked;
        }
    }

Get your list like this which you want to show in the list view

  final ArrayList<CommonCategory> commonFriends = new ArrayList<CommonCategory>();


  for (FriendsDataClass friendsDataClass : XMPPConn.mfriendList) {
                String usernameEmail = friendsDataClass.friendName;
                String username = usernameEmail.substring(0,
                        usernameEmail.indexOf("@"));


                    CommonCategory commoncontacts = new CommonCategory();
                    commoncontacts.setUsernameEmail(usernameEmail);
                    commoncontacts.setName(username);
                    commoncontacts.setChecked(false);
                    commonFriends.add(commoncontacts);



        }

And do set your checkbox value in onCompoundButton in the getView itself, and set is to the getter setter. This way you can do it very easily.

Thanks

Get data from all rows in ListView with CustomViews

1 Answers1