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spinner - How can I use onItemSelected in Android?

package org.example.mbtiapplication;

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.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

public class MBTITest extends Activity implements OnItemSelectedListener  {

    private Spinner firstSpinner;

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

        Spinner firstSpinner = (Spinner) findViewById(R.id.spinner1);
        // Create an ArrayAdapter using the string array and a default spinner layout
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
                R.array.spinnerarraybool, android.R.layout.simple_spinner_item);
        // Specify the layout to use when the list of choices appears
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        // Apply the adapter to the spinner
        firstSpinner.setAdapter(adapter);
    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View v, int position,
            long id) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onNothingSelected(AdapterView<?> arg0) {
        // TODO Auto-generated method stub      
    } 
}

XML Layout:

<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:layout_width="120dp"
            android:layout_height="match_parent"
            android:layout_marginLeft="5dp"
            android:gravity="center_vertical"
            android:text="I like to go out more than staying home." />

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />
    </TableRow>

    <TableRow
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:layout_width="120dp"
            android:layout_height="match_parent"
            android:layout_marginLeft="5dp"
            android:gravity="center_vertical"
            android:textSize="10.5dp"
            android:text="Sensing v Intuition" />

        <Spinner
            android:id="@+id/spinner2"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </TableRow>
</TableLayout>

I'm a new Android programmer and having trouble with using Spinner, i've tried multiple tutorials and still am confused. I'd like to know what my next step is here, as far as I know I have set up my spinner in XML, in Java I have identified that spinner, created an ArrayAdapter for said spinner, and specified some options. I'm not to sure if I have populated the spinner yet or how to manuever with the spinner object. I'd like to be able to use the spinner object to select one of three options and then keep that value inside of the textview inside of the spinner.

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1 Reply

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by (71.8m points)

You're almost there. As you can see, the onItemSelected will give you a position parameter, you can use this to retrieve the object from your adapter, as in getItemAtPosition(position).

Example:

spinner.setOnItemSelectedListener(this);

...

public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
    Toast.makeText(parent.getContext(), 
        "OnItemSelectedListener : " + parent.getItemAtPosition(pos).toString(),
        Toast.LENGTH_SHORT).show();
}

This will put a message on screen, with the selected item printed by its toString() method.


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