Lesson 3– Spinner

Create a new class, name it third.

Right click to folder layout, New > Android XML File, name it ac3, finish.

Edit code to make it look like this.

public class third extends Activity {

         

          @Override

          protected void onCreate(Bundle savedInstanceState) {

               super.onCreate(savedInstanceState);

               setContentView(R.layout.ac3);

}

}

Copy in to file ac3.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="match_parent"

    android:orientation="vertical" >

    <TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_gravity="center_horizontal"

        android:layout_marginTop="5dp"

        android:text="Lunar year:"

        android:textColor="#800000"

        android:textSize="20sp" />

    <TextView

        android:id="@+id/tv"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_gravity="center_horizontal"

        android:layout_marginTop="5dp"

        android:textColor="#000080"

        android:textSize="20sp" />

    <TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_gravity="center_horizontal"

        android:layout_marginTop="5dp"

        android:text="Choose year:"

        android:textColor="#800000"

        android:textSize="20sp" />

    <Spinner

        android:id="@+id/spin1"

        android:layout_width="72dp"

        android:layout_height="45dp"

        android:layout_gravity="center_horizontal"

        android:layout_marginTop="15dp"

        android:background="#a1caf1"

        android:lineSpacingExtra="4dp"

        android:textAppearance="?android:attr/textAppearanceSmall" />

    <LinearLayout

        android:layout_width="wrap_content"

        android:layout_height="41dp"

        android:layout_gravity="center_horizontal"

        android:layout_marginTop="15dp" >

        <Button

            android:id="@+id/bu1"

            android:layout_width="65dp"

            android:layout_height="40dp"

            android:layout_marginLeft="4dp"

            android:text="Quit"

            android:textColor="#0000cd"

            android:textSize="14sp" />

    </LinearLayout>

</LinearLayout>

Double click to file AndroidManifest.xml to declare new class.

In class third, declare textView, Spinner, Button, find address.

Spinner show a list of data items, we can choose what we need, no need enter from keyboard.

Declare an array and adapter.

String[] data = { "2010", "2011", "2012", "2013", "2014",

               "2015", "2016", "2017", "2018", "2019", "2020"};  

private ArrayAdapter<String> adapter;

Import library.

Code now look like this.

Copy to below findViewById.

adapter = new ArrayAdapter<String>(third.this, android.R.layout.simple_spinner_item,data);

            sp.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

          @Override

     public void onItemSelected(AdapterView<?> parent, View view,

               int position, long id) {

          String year = sp.getSelectedItem().toString();

                    

                      

               }

               @Override

               public void onNothingSelected(AdapterView<?> arg0) {

                     // TODO Auto-generated method stub

               }

          });

     sp.setAdapter(adapter);

Here we set adapter for spinner to make it show list, class now look like this.

Back to MainActivity change code in Next button to.

Intent in = new Intent(MainActivity.this,third.class);                 

startActivity(in);

Run to see new class show spinner.

Copy function change year to above last close bracket.

public String lunaryear(int year){

          int remain=year%12;

          String lunar="";

          if(remain==1){

               lunar="Rooster";

          }

          else if(remain==2){

               lunar="Dog";

          }

          else if(remain==3){

               lunar="Pig";

          }

          else if(remain==4){

               lunar="Rat";

          }

          else if(remain==5){

               lunar="Cow";

          }

          else if(remain==6){

               lunar="Tiger";

          }

          else if(remain==7){

               lunar="Rabbit";

          }

          else if(remain==8){

               lunar="Dragon";

          }

          else if(remain==9){

               lunar ="Snake";

          }

          else if(remain==10){

               lunar="Horse";

          }

          else if(remain==11){

               lunar="Goat";

          }

          else {

               lunar="Monkey";

          }

          return lunar;

     }

In Spinner, we get string user choose by.

String year = sp.getSelectedItem().toString();

We cast it to number by this.

int year2 = Integer.parseInt(year);

No need try catch because our data not contain text inside.

After that, call function to change it to lunar year, set result to textView.

String lunar = lunaryear(year2);

tv.setText(lunar);

Run to see result.

Now we want spinner show year 2018 when open screen. Add this line to below setAdapter.

sp.setSelection(8);

Value 2018 is the eighth element, so we set i=7 because i=0 mean first element.

Code Quit button with command finish().

If our data array contain blank character in numbers, we can use trim() to remove them.

year=year.trim();

Change font size, text color in file ac3.xml  for more practical.

To change Hex code in line android:textColor="#0000cd" search Hex code color online.