การใช้งาน ListView | Phaisarn Sutheebanjard

ListView

สร้าง ListView เปล่าๆ ไว้ที่ activity_main.xml
จากนั้นเพิ่มข้อมูลด้วยโค๊ด พร้อมใส่อีเวนท์คลิกที่ไอเทม setOnItemClickListener

แก้ไขโค๊ดทีไ่ฟล์ activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <Button
            android:id="@+id/button1"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Click Me" />

        <ListView
            android:id="@+id/listView1"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:padding="5dp" />

    </LinearLayout>

</android.support.constraint.ConstraintLayout>

<?xml version="1.0" encoding="utf-8"?>

<android.support.constraint.ConstraintLayout

xmlns:android="http://schemas.android.com/apk/res/android"

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context=".MainActivity">

<LinearLayout

android:layout_width="match_parent"

android:layout_height="match_parent"

android:orientation="vertical">

<Button

android:id="@+id/button1"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:text="Click Me" />

<ListView

android:id="@+id/listView1"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:padding="5dp" />

</LinearLayout>

</android.support.constraint.ConstraintLayout>

แก้ไขโค๊ดทีไ่ฟล์ MainActivity.java

package com.phaisarn.jack.testlistapplication;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button button1 = findViewById(R.id.button1);
        button1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(getApplicationContext(), "HelloWorld",
                        Toast.LENGTH_SHORT).show();
            }
        });


        ArrayList arrayList = new ArrayList();
        arrayList.add("Trace 1");
        arrayList.add("Trace 2");
        arrayList.add("Trace 3");
        arrayList.add("Trace 4");
        arrayList.add("Trace 5");

        // Get reference of widgets from XML layout
        final ListView listView1 = (ListView) findViewById(R.id.listView1);

        // Create a List from String Array elements
        final List<String> fruits_list = new ArrayList<String>(arrayList);

        // Create an ArrayAdapter from List
        final ArrayAdapter<String> arrayAdapter = 
            new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, fruits_list);

        // DataBind ListView with items from ArrayAdapter
        listView1.setAdapter(arrayAdapter);

        listView1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                String selectedItem = parent.getItemAtPosition(position).toString();
                Toast.makeText(getApplicationContext(), selectedItem, Toast.LENGTH_SHORT).show();
            }
        });

    }
}

package com.phaisarn.jack.testlistapplication;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.view.View;

import android.widget.AdapterView;

import android.widget.ArrayAdapter;

import android.widget.Button;

import android.widget.ListView;

import android.widget.Toast;

import java.util.ArrayList;

import java.util.List;

public class MainActivity extends AppCompatActivity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Button button1 = findViewById(R.id.button1);

button1.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

Toast.makeText(getApplicationContext(), "HelloWorld",

Toast.LENGTH_SHORT).show();

}

});

ArrayList arrayList = new ArrayList();

arrayList.add("Trace 1");

arrayList.add("Trace 2");

arrayList.add("Trace 3");

arrayList.add("Trace 4");

arrayList.add("Trace 5");

// Get reference of widgets from XML layout

final ListView listView1 = (ListView) findViewById(R.id.listView1);

// Create a List from String Array elements

final List<String> fruits_list = new ArrayList<String>(arrayList);

// Create an ArrayAdapter from List

final ArrayAdapter<String> arrayAdapter =

new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, fruits_list);

// DataBind ListView with items from ArrayAdapter

listView1.setAdapter(arrayAdapter);

listView1.setOnItemClickListener(new AdapterView.OnItemClickListener() {

@Override

public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

String selectedItem = parent.getItemAtPosition(position).toString();

Toast.makeText(getApplicationContext(), selectedItem, Toast.LENGTH_SHORT).show();

}

});

}

ปล. ถ้า ListView นี้อยู่ใน Fragment อีกที ตรง Toast ให้เปลี่ยน จาก getApplicationContext() เป็น getActivity()

Toast.makeText(getActivity(), selectedItem, Toast.LENGTH_SHORT).show();

1	Toast.makeText(getActivity(), selectedItem, Toast.LENGTH_SHORT).show();