How to add ListView items on button click using adapter

问题

How to take data that was typed in EditText and by clicking "submit" in that window should add it to previous activity listview items? What I need to do is:

Creating EditText and submit button
Creating listview in same Activity
By clicking submit button it should display it in listview.

I saw this similar question here:add items to listview dynamically android

But i couldn't understand the answer.Somebody please explain how to do this.

回答1:

You just do the following : Prepare your xml like this :

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

  <EditText
     android:id="@+id/editText"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_alignParentTop="true"
     android:layout_toLeftOf="@+id/addItem"
     android:hint="Add a new item to List View" />

  <Button
     android:id="@+id/addItem"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_alignParentRight="true"
     android:text="Add" /> 

  <ListView
     android:id="@+id/listView"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_below="@+id/editText" >
  </ListView>

</RelativeLayout>

Activity looks like following :

public class MainActivity extends Activity {
    EditText editText;
    Button addButton;
    ListView listView;
    ArrayList<String> listItems;
    ArrayAdapter<String> adapter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        editText = (EditText) findViewById(R.id.editText);
        addButton = (Button) findViewById(R.id.addItem);
        listView = (ListView) findViewById(R.id.listView);
        listItems = new ArrayList<String>();
        listItems.add("First Item - added on Activity Create");
        adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, listItems);
        listView.setAdapter(adapter);
        addButton.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
                listItems.add(editText.getText().toString());
                adapter.notifyDataSetChanged();
            }
        });
        listView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> a, View v, int position,
                    long id) {
                Toast.makeText(MainActivity.this, "Clicked", Toast.LENGTH_LONG)
                        .show();
            }
        });
    }
}

回答2:

Create String Arraylist and initialize it

    ArrayList<String> str1 = new ArrayList<String>();

Add some values on it

     str1.add("First Row");
     str1.add("Second Row");
     str1.add("Third Row");
     str1.add("Fourth Row");
     str1.add("Fifth Row");

Then set Adapter to ListView

adapter=new ListAdapter(this,str1);
list.setAdapter(adapter);

then add your EditText text into str1 and then called adapter.notifyDataSetChanged(); like

str1.add(edit_message.getText().toString());
adapter.notifyDataSetChanged();

Try to add this code into Button onclick()

Demo Output:

回答3:

Suppose you have an arraylist

ArrayList<String> dataList = new Arraylist ();

So On clicking of button, you need to add the new data item into your data arraylist.

For this first take the value entered in edittext and store in a string.

String editedValue = yourEditText.getText.toString();

Then we need to add this in our datalist.

dataList.add(editedValue);

And then just call adapter.notifyDataSetChanged()

yourAdapter.notifyDataSetChanged();

It will work.

来源：https://stackoverflow.com/questions/22144891/how-to-add-listview-items-on-button-click-using-adapter

标签

android

android-listview