// UC.javapackage com.apress.uc;import android.app.Activity;import android.os.Bundle;import android.text.Editable;import android.text.TextWatcher;import android.view.View;import android.widget.AdapterView;import android.widget.ArrayAdapter;import android.widget.Button;import android.widget.EditText;import android.widget.Spinner;public class UC extends Activity{   private int position = 0;   private double[] multipliers =   {      0.0015625,         // Acres to square miles      101325.0,          // Atmospheres to Pascals      100000.0,          // Bars to Pascals      0,                 // Degrees Celsius to Degrees Fahrenheit (placeholder)      0,                 // Degrees Fahrenheit to Degrees Celsius (placeholder)      0.00001,           // Dynes to Newtons      0.3048,            // Feet/Second to Metres/Second      0.0284130625,      // Fluid Ounces (UK) to Litres      0.0295735295625,   // Fluid Ounces (US) to Litres      746.0,             // Horsepower (electric) to Watts      735.499,           // Horsepower (metric) to Watts      1/1016.0469088,    // Kilograms to Tons (UK or long)      1/907.18474,       // Kilograms to Tons (US or short)      1/0.0284130625,    // Litres to Fluid Ounces (UK)      1/0.0295735295625, // Litres to Fluid Ounces (US)      331.5,             // Mach Number to Metres/Second      1/0.3048,          // Metres/Second to Feet/Second      1/331.5,           // Metres/Second to Mach Number      0.833,             // Miles/Gallon (UK) to Miles/Gallon (US)      1/0.833,           // Miles/Gallon (US) to Miles/Gallon (UK)      100000.0,          // Newtons to Dynes      1/101325.0,        // Pascals to Atmospheres      0.00001,           // Pascals to Bars      640.0,             // Square Miles to Acres      1016.0469088,      // Tons (UK or long) to Kilograms      907.18474,         // Tons (US or short) to Kilograms      1/746.0,           // Watts to Horsepower (electic)      1/735.499          // Watts to Horsepower (metric)   };   @Override   public void onCreate(Bundle savedInstanceState)   {      super.onCreate(savedInstanceState);      setContentView(R.layout.main);      final EditText etUnits = (EditText) findViewById(R.id.units);      final Spinner spnConversions = (Spinner) findViewById(R.id.conversions);      ArrayAdapter<CharSequence> aa;      aa = ArrayAdapter.             createFromResource(this, R.array.conversions,                                android.R.layout.simple_spinner_item);      aa.setDropDownViewResource(android.R.layout.simple_spinner_item);      spnConversions.setAdapter(aa);      AdapterView.OnItemSelectedListener oisl;      oisl = new AdapterView.OnItemSelectedListener()      {         @Override         public void onItemSelected(AdapterView<?> parent, View view,                                    int position, long id)         {            UC.this.position = position;         }         @Override         public void onNothingSelected(AdapterView<?> parent)         {            System.out.println("nothing");         }      };      spnConversions.setOnItemSelectedListener(oisl);      final Button btnClear = (Button) findViewById(R.id.clear);      AdapterView.OnClickListener ocl;      ocl = new AdapterView.OnClickListener()      {         @Override         public void onClick(View v)         {            etUnits.setText("");         }      };      btnClear.setOnClickListener(ocl);      btnClear.setEnabled(false);      final Button btnConvert = (Button) findViewById(R.id.convert);      ocl = new AdapterView.OnClickListener()      {         @Override         public void onClick(View v)         {            String text = etUnits.getText().toString();            double input = Double.parseDouble(text);            double result = 0;            if (position == 3)               result = input*9.0/5.0+32; // Celsius to Fahrenheit            else            if (position == 4)               result = (input-32)*5.0/9.0; // Fahrenheit to Celsius            else               result = input*multipliers[position];            etUnits.setText(""+result);         }      };      btnConvert.setOnClickListener(ocl);      btnConvert.setEnabled(false);      Button btnClose = (Button) findViewById(R.id.close);      ocl = new AdapterView.OnClickListener()      {         @Override         public void onClick(View v)         {            finish();         }      };      btnClose.setOnClickListener(ocl);      TextWatcher tw;      tw = new TextWatcher()      {         @Override         public void afterTextChanged(Editable s)         {         }         @Override         public void beforeTextChanged(CharSequence s, int start, int count,                                       int after)         {         }         @Override         public void onTextChanged(CharSequence s, int start, int before,                                   int count)         {            if (etUnits.getText().length() == 0)            {               btnClear.setEnabled(false);               btnConvert.setEnabled(false);            }            else            {               btnClear.setEnabled(true);               btnConvert.setEnabled(true);            }         }      };      etUnits.addTextChangedListener(tw);   }}

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"   android:orientation="vertical"   android:layout_width="fill_parent"   android:layout_height="fill_parent"   android:gravity="center_vertical"   android:background="@drawable/gradientbg"   android:padding="5dip">   <LinearLayout android:layout_width="fill_parent"      android:layout_height="wrap_content">      <TextView android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_marginRight="10dip"         android:text="@string/units"         android:textColor="#000000"         android:textSize="15sp"         android:textStyle="bold"/>      <EditText android:id="@+id/units"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:hint="type a number"         android:inputType="numberDecimal|numberSigned"         android:maxLines="1"/>   </LinearLayout>   <Spinner android:id="@+id/conversions"      android:layout_width="fill_parent"      android:layout_height="wrap_content"      android:prompt="@string/prompt"/>   <LinearLayout android:layout_width="fill_parent"      android:layout_height="wrap_content">      <Button android:id="@+id/clear"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_weight="1"         android:text="@string/clear"/>      <Button android:id="@+id/convert"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_weight="1"         android:text="@string/convert"/>      <Button android:id="@+id/close"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_weight="1"         android:text="@string/close"/>   </LinearLayout></LinearLayout>

<?xml version="1.0" encoding="utf-8"?><resources>   <string name="app_name">Units Converter</string>   <string name="clear">Clear</string>   <string name="close">Close</string>   <string name="convert">Convert</string>   <string name="prompt">Select a conversion</string>   <string name="units">Units</string></resources>

<?xml version="1.0" encoding="utf-8"?><resources>   <string-array name="conversions">      <item>Acres to Square Miles</item>      <item>Atmospheres to Pascals</item>      <item>Bars to Pascals</item>      <item>Degrees Celsius to Degrees Fahrenheit</item>      <item>Degrees Fahrenheit to Degrees Celsius</item>      <item>Dynes to Newtons</item>      <item>Feet/Second to Metres/Second</item>      <item>Fluid Ounces (UK) to Litres</item>      <item>Fluid Ounces (US) to Litres</item>      <item>Horsepower (electric) to Watts</item>      <item>Horsepower (metric) to Watts</item>      <item>Kilograms to Tons (UK or long)</item>      <item>Kilograms to Tons (US or short)</item>      <item>Litres to Fluid ounces (UK)</item>      <item>Litres to Fluid ounces (US)</item>      <item>Mach Number to Metres/Second</item>      <item>Metres/Second to Feet/Second</item>      <item>Metres/Second to Mach Number</item>      <item>Miles/Gallon (UK) to Miles/Gallon (US)</item>      <item>Miles/Gallon (US) to Miles/Gallon (UK)</item>      <item>Newtons to Dynes</item>      <item>Pascals to Atmospheres</item>      <item>Pascals to Bars</item>      <item>Square Miles to Acres</item>      <item>Tons (UK or long) to Kilograms</item>      <item>Tons (US or short) to Kilograms</item>      <item>Watts to Horsepower (electric)</item>      <item>Watts to Horsepower (metric)</item>   </string-array></resources>

<?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android">   <gradient android:startColor="#fccb06"       android:endColor="#fd6006"      android:angle="270"/>   <corners android:radius="10dp"/></shape>

<menu xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    tools:context="com.apress.uc.UC" ></menu>