adapter not active by any kind

Question

I am a new Developer, I tried using adapter on my project,android app stopped unfortulately without showing any error. Tried grid view, image view and spinner, but in all cases my app stopped unfortunately without showing any error Here I tried spinner with custom adapter Tried array adapter in one class, it ran but I need a Separate class for adapter and call it by another class

MainActivity

 package com.safaa.user.last_app;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Spinner;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
String [] fruit={
        "apple","panana","orange"
};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Spinner spinner=findViewById(R.id.spinner);
        CustomSpinnerAdapter spinnerAdapter=new CustomSpinnerAdapter(this,fruit);
        spinner.setAdapter(spinnerAdapter);
        spinner.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int i, long id) {

                Toast.makeText(MainActivity.this,fruit[i],Toast.LENGTH_SHORT).show();
            }

            public void onNothingSelected(AdapterView<?>adapterView){

            }
        });
    }
}

Main.xml

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

    <android.support.v7.widget.AppCompatSpinner
        android:layout_width="200dp"
        android:layout_height="50dp"
        android:id="@+id/spinner"
        android:layout_centerHorizontal="true">

    </android.support.v7.widget.AppCompatSpinner>
</RelativeLayout>

CustomSpinnerAdapter

package com.safaa.user.last_app;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.zip.Inflater;

import static com.safaa.user.last_app.R.layout.spinner_row;

public class CustomSpinnerAdapter extends BaseAdapter {
    Activity activity;
    String []fruit;
    LayoutInflater inflater;

@SuppressLint("ServiceCast")
public CustomSpinnerAdapter (Activity activity, String [] fruit){
this.activity=activity;
this.fruit=fruit;
    inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);


    }

    @Override
    public int getCount() {
        return fruit.length;
    }

    @Override
    public Object getItem(int position) {
        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
View row      = inflater.inflate(R.layout.spinner_row,null);

        TextView textView=(TextView)row.findViewById(R.id.txt1);
        textView.setText(fruit[i]);
        return row;
    }
}

spinner_row.xml

<?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="40dp">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/txt1"
        android:layout_marginLeft="10dp"
        />


</LinearLayout>

Answer 1

You need to update those two method :

@Override
public String getItem(int position) {
    return fruit[position];
}

@Override
public long getItemId(int position) {
    return position;
}

also you need to use ItemSelectedListener with Spinner not ItemClickListener change to the code below :

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
                Toast.makeText(MainActivity.this,fruit[i],Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {

            }
        });