How To Design A Temperature Conversion App

This is another simple android application which converts temperature into Celsius and Fahrenheit. Here we are taking a temperature value in edit text box and checking radio buttons and converting into checked temperature. So, create your new project and drop one edit box, two radio buttons, one text view and one simple button. The code of android XML file is given below:

Temperature conversion application in Android

                              <LinearLayout                xmlns:android=                "http://schemas.android.com/apk/res/android"                android:id=                "@+id/ll"                android:layout_width=                "fill_parent"                android:layout_height=                "fill_parent"                android:orientation=                "vertical"                >                <EditText                android:id=                "@+id/editText1"                android:layout_width=                "match_parent"                android:layout_height=                "wrap_content"                android:inputType=                "numberDecimal"                >                </EditText>                <TextView                android:id=                "@+id/result"                android:layout_width=                "wrap_content"                android:layout_height=                "wrap_content"                android:textSize=                "30sp"                />                <RadioGroup                android:id=                "@+id/radioGroup1"                android:layout_width=                "wrap_content"                android:layout_height=                "wrap_content"                >                <RadioButton                android:id=                "@+id/cb"                android:layout_width=                "wrap_content"                android:layout_height=                "wrap_content"                android:checked=                "true"                android:text=                "Celcius"                />                <RadioButton                android:id=                "@+id/fb"                android:layout_width=                "wrap_content"                android:layout_height=                "wrap_content"                android:text=                "Fahrenhiet"                />                </RadioGroup>                <Button                android:id=                "@+id/button1"                android:layout_width=                "wrap_content"                android:layout_height=                "wrap_content"                android:onClick=                "add"                android:text=                "Convert"                android:textSize=                "30sp"                />                </LinearLayout>

Now open your Java file and initialize all objects. Get value from edit text box in a double type variable and convert into given temperature according to checked radio button and display it to text view. The code of android Java file is given with explanation:

              package              com.              innosen              ;              //your package name                            import              android.os.Bundle              ;              import              android.view.View              ;              import              android.widget.EditText              ;              import              android.widget.LinearLayout              ;              import              android.widget.RadioButton              ;              import              android.widget.TextView              ;              import              android.app.Activity              ;              import              android.graphics.Color              ;

              public              class              MainActivity              extends              Activity              {              @Override              protected              void              onCreate              (Bundle savedInstanceState)              {              super              .              onCreate              (savedInstanceState);              setContentView(R.              layout              .              activity_main              );              }              public              void              add              (View v)              {              LinearLayout ll=(LinearLayout)findViewById(R.              id              .              ll              );              TextView result=(TextView)findViewById(R.              id              .              result              );              EditText et1=(EditText)findViewById(R.              id              .              editText1              );

              //get value from edit text box and convert into double              double              a=Double.              parseDouble              (String.              valueOf              (et1.              getText              ()));              RadioButton cb=(RadioButton)findViewById(R.              id              .              cb              );              RadioButton fb=(RadioButton)findViewById(R.              id              .              fb              );

              //check which radio button is checked              if              (cb.              isChecked              ())              {              //change background colour                            ll.              setBackgroundColor              (Color.              YELLOW              );              //display conversion              result.              setText              (f2c(a)+              " degree C"              );              //cb.setChecked(false);              fb.              setChecked              (              true              );              }              else              {              ll.              setBackgroundColor              (Color.              CYAN              );              result.              setText              (c2f(a)+              " degree F"              );              //fb.setChecked(false);              cb.              setChecked              (              true              );              }              }              //Celcius to Fahrenhiet method                            private              double              c2f              (              double              c)              {              return              (c*9)/5+32;              }              //Fahrenhiet to Celcius method              private              double              f2c              (              double              f)              {              return              (f-32)*5/9;              }              }