Android: Spanish: issue while parsing float value : App crashes

Question

Android: Spanish: issue while parsing float value : App crashes Steps:

1.set language as spanish in app

2.format some float value to single decimal

3.parse the formated value to again float

App crashes.

sample code given below:

Please help if you have any idea about this.

 TextView textView = null;
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            textView = (TextView) findViewById(R.id.textview);
            float value = 3.456789f;
            setLocale("es", this);//Set App language as Spanish
            String parsedString = String.format("%.1f", value); // format the float value to single precision 
            float parsedValueFloat = Float.parseFloat(parsedString); // parse the value again to float.(APP Crashesh here)
            textView.setText(parsedValueFloat+"");
    }

        public static void setLocale(String languageCode, Context ctx) {
            Locale locale = new Locale(languageCode);
            Locale.setDefault(locale);
            Configuration config = new Configuration();
            config.locale = locale;
            ctx.getResources().updateConfiguration(config,
                    ctx.getResources().getDisplayMetrics());
        }

Crash logs given below :

 01-06 20:41:00.265: E/AndroidRuntime(3153): java.lang.RuntimeException: Unable to start      activity ComponentInfo{com.example.testcanvas/com.example.testcanvas.MainActivity}: java.lang.NumberFormatException: Invalid float: "3,5"
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2295)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread.access$700(ActivityThread.java:159)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.os.Handler.dispatchMessage(Handler.java:99)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.os.Looper.loop(Looper.java:137)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread.main(ActivityThread.java:5419)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at java.lang.reflect.Method.invokeNative(Native Method)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at java.lang.reflect.Method.invoke(Method.java:525)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at dalvik.system.NativeStart.main(Native Method)
            01-06 20:41:00.265: E/AndroidRuntime(3153): Caused by: java.lang.NumberFormatException: Invalid float: "3,5"
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at java.lang.StringToReal.invalidReal(StringToReal.java:63)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at java.lang.StringToReal.parseFloat(StringToReal.java:310)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at java.lang.Float.parseFloat(Float.java:300)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at com.example.testcanvas.MainActivity.onCreate(MainActivity.java:31)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.Activity.performCreate(Activity.java:5372)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2257)
            01-06 20:41:00.265: E/AndroidRuntime(3153):     ... 11 more

Answer 1

This happens because the localised output of floats/doubles to strings, in this case (and many other languages - you've noted Spanish, Italian, Russian, there's also French and others), uses a comma rather than a period:

3,5

instead of

3.5

Since Float.parse() expects an "en" locale formatted string, the way to do this is to use the NumberFormat class, as per this answer:

NumberFormat nf = NumberFormat.getInstance(Locale.forLanguageTag("es"));
Number parsedNumber = nf.parse(parsedString);
float parsedValueFloat = parsedNumber.floatValue();