There is an issue with using RoundingMode.DOWN to truncate extra decimal digits (to prevent RoundingMode.UP) This Pull Request adds a custom helper method to truncate those extra decimal digits; tested extensively with Unit Tests.

Fixes #29

It would be interesting if it was delimited correctly depending on how the android device is configured and also if you want to show another type of currency. I hope it helps

Extract info decimal formater

        val nf: NumberFormat = NumberFormat.getCurrencyInstance(Locale.getDefault())

        if (nf is DecimalFormat) {
            val sym: DecimalFormatSymbols = nf.decimalFormatSymbols

            Log.d(TAG, "currency: " + sym.currency)
            Log.d(TAG, "currencySymbol: " + sym.currencySymbol)
            Log.d(TAG, "decimalSeparator: " + sym.decimalSeparator)
            Log.d(TAG, "digit: " + sym.digit)
            Log.d(TAG, "exponentSeparator: " + sym.exponentSeparator)
            Log.d(TAG, "groupingSeparator: " + sym.groupingSeparator)
            Log.d(TAG, "infinity: " + sym.infinity)
            Log.d(TAG, "internationalCurrencySymbol: " + sym.internationalCurrencySymbol)
            Log.d(TAG, "minusSign: " + sym.minusSign)
            Log.d(TAG, "monetaryDecimalSeparator: " + sym.monetaryDecimalSeparator)
            Log.d(TAG, "naN: " + sym.naN)
            Log.d(TAG, "patternSeparator: " + sym.patternSeparator)
            Log.d(TAG, "perMill: " + sym.perMill)
            Log.d(TAG, "percent: " + sym.percent)
            Log.d(TAG, "zeroDigit: " + sym.zeroDigit)
        }

Set my devices in Spanish/Spain

Decimal Format detail

D/: currency: EUR
D/: currencySymbol: €
D/: decimalSeparator: ,
D/: digit: #
D/: exponentSeparator: E
D/: groupingSeparator: .
D/: infinity: ∞
D/: internationalCurrencySymbol: EUR
D/: minusSign: -
D/: monetaryDecimalSeparator: ,
D/: naN: NaN
D/: patternSeparator: ;
D/: perMill: ‰
D/: percent: %
D/: zeroDigit: 0

Print currency format

nf.format(2536) //2.536,00 €
nf.format(2536.3321F) //2.536,33 €
nf.format(999999999999999) //999.999.999.999.999,00 €
nf.format(0) //0,00 €
nf.format(-31) //-31,00 €
nf.format(-31.83F) //-31,83 €

Set my devices in Enghish/USA

Decimal Format detail

D/FirstFragment: currency: USD
D/FirstFragment: currencySymbol: $
D/FirstFragment: decimalSeparator: .
D/FirstFragment: digit: #
D/FirstFragment: exponentSeparator: E
D/FirstFragment: groupingSeparator: ,
D/FirstFragment: infinity: ∞
D/FirstFragment: internationalCurrencySymbol: USD
D/FirstFragment: minusSign: -
D/FirstFragment: monetaryDecimalSeparator: .
D/FirstFragment: naN: NaN
D/FirstFragment: patternSeparator: ;
D/FirstFragment: perMill: ‰
D/FirstFragment: percent: %
D/FirstFragment: zeroDigit: 0

Print currency format

nf.format(2536) //$2,536.00
nf.format(2536.3321F) //$2,536.33
nf.format(999999999999999) //$999,999,999,999,999.00
nf.format(0) //$0.00
nf.format(-31) //-$31.00
nf.format(-31.83F) //-$31.83

Devices in English/USA

represent a currency different from that established by the system

 nf.currency = Currency.getInstance("EUR")

result view that the euro symbol is displayed at the beginning, as is the system set by the user

nf.format(2536) //€2,536.00
nf.format(2536.3321F) //€2,536.33
nf.format(999999999999999) //€999,999,999,999,999.00
nf.format(0) //€0.00
nf.format(-31) //-€31.00
nf.format(-31.83F) //-€31.83

Extra

Get available currencies

listCurrencies = Currency.getAvailableCurrencies()
    .filter { !it.displayName.contains("(") }
    .sortedBy { it.currencyCode }
    .map { it.displayName }

First, focus in front of the currency selected symbol

Then enter the number 1, 2

Will be displayed blank in the EditText and the cursor is not displayed in front of the text. @codedentwickler

An example:

val amount = "515.809"
currencyEditText.setText(amount)

A text visible in a field is expected to be 515.809 and yet it becomes 515.808. I get the same results when trying to enter 515.809 manually.

This Pull Request makes the maximum amount of decimal digits number configurable. It exposes a method and an XML attribute to configure it. Tests are also included to ensure functionality.

Currently it is hardcoded to 2 in CurrencyInputWatcher companion object but in a project I'm working on this number needs to be 3. Can this be made configurable?

If we set value to Edit Text etPrice.setText("123") then currency symbol is not visible. But its set in xml file like app:currencySymbol="$"

This PR formats output values from the CurrencyEditText using the supplied Locale. The previous implementation wrongfully formats output values using an implicit locale that assumes that the decimal symbol will always be ".". This caused issues with locales/countries that don't have "." as the decimal symbol.

Finally, the PRs adds support for getting user input as a BigDecimal

In this line: hasDecimalPoint = s.toString().contains(decimalFormatSymbols.decimalSeparator.toString()) It will check Persian, Arabic or any language specific decimals, but if developer used numeric keyboard decimal char will be "," or ".". So have to add these two characters as well. SO if we set locale to Persian or Arabic locale from phone resources.configuration.locales[0]

And enter 5.488 Result will be like this:

This Pull Request fixes Double's problem with accurately storing 1.0E23 in memory, storing 9.99999999999E22 instead. This is fixed by changing the parsed number during entry to BigDecimal from Double. BigDecimal doesn't have a problem with storing 1.0E23 or any other number in memory accurately, fixing this problem.

Another plus that comes with this fix is; Double has a limit of 1.0E308, which returns infinity after this point. BigDecimal can store as many numbers as you can type.

Fixes #17

This PR fixes #14 by adding the text watcher as soon as the edittext is initialized. It also improves setText() method calls by moving the cursor to the end of the edit text after the method call.

Investigate how easy it is to support the TextField in Jetpack compose. Check if the formatting logic can be properly extracted and used for both the View-based EditText and Compose's TextVField.

Ideally, the composing support should be exposed as an additional artefact/dependency on top of the core-library logic. We might need to do some refactoring on the existing package structure.

Very large amount resulted in rounding error in display. Entered 1 followed by zeros...eventually saw $ 99,999,999,999,999,990,000,000 when value should have been $ 100,000,000,000,000,000,000,000

Using Android Studio 4.2 Beta 6 Build #AI-202.7660.26.42.7188722, built on March 5, 2021 Runtime version: 11.0.8+10-b944.6916264 x86_64 VM: OpenJDK 64-Bit Server VM by N/A macOS 10.15.7

And AVD: Name: Nexus_10_API_27 CPU/ABI: Google APIs Intel Atom (x86) Path: /Users/michaelhampton/.android/avd/Nexus_10_API_27.avd Target: google_apis [Google APIs] (API level 27) Skin: nexus_10 SD Card: 100M hw.dPad: no hw.lcd.height: 1600 runtime.network.speed: full hw.accelerometer: yes hw.device.name: Nexus 10 vm.heapSize: 192 skin.dynamic: yes hw.device.manufacturer: Google hw.lcd.width: 2560 hw.gps: yes hw.initialOrientation: Portrait image.androidVersion.api: 27 hw.audioInput: yes image.sysdir.1: system-images/android-27/google_apis/x86/ tag.id: google_apis showDeviceFrame: yes hw.camera.back: virtualscene hw.mainKeys: no AvdId: Nexus_10_API_27 hw.camera.front: emulated hw.lcd.density: 320 avd.ini.displayname: Nexus 10 API 27 hw.arc: false hw.gpu.mode: auto hw.device.hash2: MD5:813203ac93d1d63cd91f729c376b1f3e hw.ramSize: 1536 hw.trackBall: no PlayStore.enabled: false fastboot.forceColdBoot: no hw.battery: yes hw.cpu.ncore: 4 hw.sdCard: yes tag.display: Google APIs runtime.network.latency: none hw.keyboard: yes hw.sensors.proximity: no disk.dataPartition.size: 800M hw.sensors.orientation: yes avd.ini.encoding: UTF-8 hw.gpu.enabled: yes

When using it from a US locale, it works perfectly. You can choose when to use the decimal etc... But when using for a locale like European where they use the "," instead of the ".", you can not choose the "," (or even the ".") to denote decimal place.

Similarly, when displaying the price, it does not seem correctly format it for the locale, using "." instead of ",".