Develop Reference

How to add images when using spinner

I am a beginner at using Android Studio Java, I have been assigned to make a dropdown list with all the car names. I have to include 30 car images but to start things off I am trying to include 5 images, I have been trying to add an image on each of the cars that are on the dropdown list. I figured out how to do the spinner and I have the code for it but now when I click on the dropdown list and click the Ford car and I want the images to appear as well.
For the main.java (called Activity2.java) here is the code for it
package com.example.myapplication;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.Spinner;
import android.widget.Toast;
import java.lang.reflect.Array;
import java.util.ArrayList;
public class Activity2 extends AppCompatActivity {
private Spinner carsSpinner;
private ImageView imageView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_2);
carsSpinner = findViewById(R.id.carsSpinner);
//final ArrayList<String> cars = new ArrayList<>();
// cars.add("Audi");
// cars.add("Bentley");
// cars.add("BMW");
// cars.add("Chevrolet");
//cars.add("Citroen");
//ArrayAdapter<String> carsAdapter = new ArrayAdapter<>(this,
android.R.layout.simple_spinner_dropdown_item, cars);
//carsSpinner.setAdapter(carsAdapter);//
carsSpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(Activity2.this, carsSpinner.getSelectedItem().toString() + " Selected",
Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
For the main activity.xml (called activity2.xml) here is the code for it, I know I have to include the ImageView there.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Spinner
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="50dp"
android:id="#+id/carsSpinner"
android:entries="#array/cars"/>
</RelativeLayout>
For the string.xml here is the code for it
<resources>
<string name="app_name">My Application</string>
<string-array name="cars">
<item>Audi</item>
<item>Bentley</item>
<item>BMW</item>
<item>Ferrari</item>
<item>Citroen</item>
</string-array>
This is how my application is looking but now I want to include the car image for each car on it, it will mean a lot if you guys could show me through the right direction.

You have to make a custom layout and adapter.
More information on how to implement it on the link below:
https://www.codingdemos.com/android-custom-spinner-images-text/

Facing problem in findView (Android Studio)

I'm new on Android Studio and I'm working on a project.
I'm facing this error
I've declared listview but don't know why it's not working.
CODE:
package com.example.animation;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class view_rooms extends AppCompatActivity {
ListView listView;
String mTitle[]={"Room1","Room2","Room3","Room4","Room5"};
String mDescription[]={"Access Room1","Access Room2","Access Room3","Access Room4","Access Room5"};
int images[]={R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_rooms);
listView=findViewById(R.id.ListView);
}

findViewById() searches the view by id into the layout file. In this case into the layout: R.layout.activity_view_rooms. You need to define into this layout one ListView widget and assign one id to search with findViewById().
For example into the layout activity_view_rooms you need to include the view:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="#+id/list_view_id"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>
</LinearLayout>
And later you can get the instance of view with finViewById() in this way:
package com.example.animation;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class view_rooms extends AppCompatActivity {
ListView listView;
String mTitle[]={"Room1","Room2","Room3","Room4","Room5"};
String mDescription[]={"Access Room1","Access Room2","Access Room3","Access Room4","Access Room5"};
int images[]={R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open,R.drawable.lights_open};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_rooms);
listView=findViewById(R.id.list_view_id);
}

You need to add this line android:id="#+id/ListView" in your activity_view_rooms.xml
So the code will looks like this:
<ListView
android:id="#+id/ListView"
android:layout_width="match_parent"
android:layout_height="match_parent">

Grid view item menu

I would like to ask how to add a menu(three points with options like the actionBar has) to a grid view item? I need it to look similar to youtube's mobile application videos: they all have these three points with a couple of options inside of them. How can I achieve this?
Here's the code:
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.GridView;
import android.widget.ListAdapter;
import java.util.ArrayList;
public class teamTasks extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.team_individual_tasks);
Button btn3 = (Button) findViewById(R.id.addTasks);
final ArrayList<String> listItemsTasks=new ArrayList<String>();
final ListAdapter addAdapterTasks = new ArrayAdapter<String>(this, R.layout.custom_box,
R.id.customBox, listItemsTasks);
GridView gvtask = (GridView) findViewById(R.id.gvTasks);
gvtask.setAdapter(addAdapterTasks);
btn3.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
listItemsTasks.add("New Task");
}
});
gvtask.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
}
});
}
}
The layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:layout_width="60dp"
android:layout_height="60dp"
android:text="+"
android:textSize="20sp"
android:id="#+id/addTasks"/>
<GridView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/addTasks"
android:id="#+id/gvTasks"
android:numColumns="2">
</GridView>
</RelativeLayout>
Custom gridView item:
<?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="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="120dp"
android:id="#+id/customBox"/>

Android ListView Integer array

I am trying to get an integer array into ListView using an adapter but do not seem to know where to begin.
I want the user to be able to open the listview, select a number from 1-99 and have the selected number be deducted from the current year and result displayed in a TextView.
Any help in the right direction would be fantastic!

first you have to create xml of listview given below
<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"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ScrollView
android:id="#+id/scrollView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" >
</ScrollView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:orientation="vertical" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
</RelativeLayout>
make one arraylist<String> list=new arraylist<string>;
add value 1-99 using for loop
and then set the array adpter on that listview as like
package com.example.arraydemo;
import java.util.ArrayList;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class MainActivity extends Activity {
ArrayList<String> list;
ListView li;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list=new ArrayList<String>();
li=(ListView)findViewById(R.id.listView1);
for(int i=1;i<=99;i++){
list.add(""+i);
}
ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(
this,
android.R.layout.simple_list_item_1,
list );
li.setAdapter(arrayAdapter);
li.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View v, int position,
long id) {
// TODO Auto-generated method stub
}
});
}
}
and ontemclicklistener you get current date from system deduct position of listview from that date

Error setListAdapter in simple program

I'm new to android programming and I still have a few things that I don't understand. For example, I'm with a program that when you click on a button, it tries to find any devices near. The problem is that I don't know how to solve a mistake I seem to have made from the beggining. This is what I have
This is the main activity:
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.ArrayAdapter;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void buscar(View view){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
List<String> s = new ArrayList<String>();
for(BluetoothDevice bt : pairedDevices)
s.add(bt.getName());
setListAdapter(new ArrayAdapter<String>(this, R.id.list, s));
}
}
And here is the xml file
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/RelativeLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<Button
android:id="#+id/botonvinculo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:clickable="true"
android:onClick="buscar"
android:text="Buscar dispositivos" />
<ListView
android:id="#+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/botonvinculo"
android:layout_below="#+id/botonvinculo" >
</ListView>
</RelativeLayout>
The thing is that I cannot make the call to setListAdapter unless my main activity extends from ListActivity, and even trying so, it returns an error saying "You must have a ListView whose attribute is "android.R.id.list".
I'd appreciate any help. Thank you very much.

If you use ListActivity then you should use android:id="#android:id/list" in your XML instead of android:id="#+id/list"
or else you can get an object of ListView in your XML like
ListView list = (ListView) findViewById(R.id.list);
and then use list.setAdapter

setListAdapter will work only when your activity extends from ListActivity. use this in your case
listview.setAdapter();
if you want to use setListAdapter() only make change these things
public class MainActivity extends Activity
to
public class MainActivity extends ListActivity
and
android:id="#android:id/list" for your list view in xml

Your class extends Activity. setListAdapter is a method of ListActivity
ListView lv;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv = (ListView)findViewById(R.id.list);
}
Then
public void buscar(View view){
BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
List<String> s = new ArrayList<String>();
for(BluetoothDevice bt : pairedDevices)
s.add(bt.getName());
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple.list_item_1,s);
lv.setAdapter(adapter);
}