Deleting Selected Items from ListView in Android

In this article, we will create an application in which users select the required items to be deleted and click on “Delete Selected Items” button for deleting them. Actually this article is an extension of the article Dynamically add items to ListView in Android, in which we have created an application to add user input text to listview. In this article, user can add as well as delete items from the listview.

1. Create an Android project namely “ListViewDeleteItems”

Figure 1: New Android Project

2. Select Build Target for this application

Figure 2: Select build target

3. Enter application details

Figure 3: Application Details

4. Open and update the file res/values/strings.xml with the given below code

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, MainActivity!</string>
    <string name="app_name">ListViewDeleteItems</string>
    <string name="hintTxtItem">Enter an item here ...</string>
    <string name="lblBtnAdd">Add Item</string>
    <string name="txtEmpty">List is empty</string>
    <string name="lblBtnDel">Delete Selected Items</string>
</resources>

5. Open and update the file res/layout/main.xml with the given below code

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

    <EditText
        android:id="@+id/txtItem"
        android:layout_width="240dp"
        android:layout_height="wrap_content"
        android:inputType="text"
        android:hint="@string/hintTxtItem"
    />

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/lblBtnAdd"
        android:layout_toRightOf="@id/txtItem"
    />

    <TextView
        android:id="@android:id/empty"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/txtItem"
        android:text="@string/txtEmpty"
        android:gravity="center_horizontal"
    />

    <ListView
        android:id="@android:id/list"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/txtItem"
        android:choiceMode="multipleChoice" >
    </ListView>

    <Button
        android:id="@+id/btnDel"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:text="@string/lblBtnDel" />
</RelativeLayout>

6. Open and update the file /src/in/wptrafficanalyzer/listviewdeleteitems/MainActivity.java with the given below code

package in.wptrafficanalyzer.listviewdeleteitems;

import java.util.ArrayList;

import android.app.ListActivity;
import android.os.Bundle;
import android.util.SparseBooleanArray;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends ListActivity {

    /** Items entered by the user is stored in this ArrayList variable */
    ArrayList list = new ArrayList();

    /** Declaring an ArrayAdapter to set items to ListView */
    ArrayAdapter adapter;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        /** Setting a custom layout for the list activity */
        setContentView(R.layout.main);

        /** Reference to the add button of the layout main.xml */
        Button btn = (Button) findViewById(R.id.btnAdd);

        /** Reference to the delete button of the layout main.xml */
        Button btnDel = (Button) findViewById(R.id.btnDel);

        /** Defining the ArrayAdapter to set items to ListView */
        adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_multiple_choice, list);

        /** Defining a click event listener for the button "Add" */
        OnClickListener listener = new OnClickListener() {
            @Override
            public void onClick(View v) {
                EditText edit = (EditText) findViewById(R.id.txtItem);
                list.add(edit.getText().toString());
                edit.setText("");
                adapter.notifyDataSetChanged();
            }
        };

        /** Defining a click event listener for the button "Delete" */
        OnClickListener listenerDel = new OnClickListener() {
            @Override
            public void onClick(View v) {
                /** Getting the checked items from the listview */
                SparseBooleanArray checkedItemPositions = getListView().getCheckedItemPositions();
                int itemCount = getListView().getCount();

                for(int i=itemCount-1; i >= 0; i--){
                    if(checkedItemPositions.get(i)){
                        adapter.remove(list.get(i));
                    }
                }
                checkedItemPositions.clear();
                adapter.notifyDataSetChanged();
            }
        };

        /** Setting the event listener for the add button */
        btn.setOnClickListener(listener);

        /** Setting the event listener for the delete button */
        btnDel.setOnClickListener(listenerDel);

        /** Setting the adapter to the ListView */
        setListAdapter(adapter);
    }
}

7. Execute the application

Figure 4: Application in execution

8. Download source code

9. Reference

http://developer.android.com/guide/index.html

How to hire me?

I am George Mathew, working as software architect and Android app developer at wptrafficanalyzer.in

You can hire me on hourly basis or on project basis for Android applications development.

For hiring me, please mail your requirements to info@wptrafficanalyzer.in.

My other blogs
store4js.blogspot.com

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Tags: checkbox, custom layout, ListActivity, listview