android numberpicker for floating point numbers
NumberPicker
is not just for integers.. Even you can use Floats
String
etc.
see this and read about it.
for tutorials :
- http://gafurbabu.wordpress.com/2012/03/29/android-number-picker-dialog/
And I had used NumberPicker
long ago like this and it might be some use posting here:
NumberPicker np;
String nums[]= {"Select Fraction","1/64","1/32","3/64","1/16","5/64","3/32","7/64","1/8","9/64","5/32","11/64","3/16","13/64","7/32","15/64","1/4","17/64","9/32","19/64","5/16","21/64","11/32","23/64","3/8","25/64","13/32","27/64","7/16","29/64"};
np = (NumberPicker) findViewById(R.id.np);
np.setMaxValue(nums.length-1);
np.setMinValue(0);
np.setWrapSelectorWheel(false);
np.setDisplayedValues(nums);
np.setDescendantFocusability(NumberPicker.FOCUS_BLOCK_DESCENDANTS);
You can make ArrayList
of any datatype and assign it.
In Kotlin, you can use this handy NumberPicker
extension dialog which scales your Double
values into a fitting Int
range and converts the Int
values back to Double
s before calling any of the callback. So it basicallly hides away the fact that NumberPicker
only supports Int
. It just feels like NumberPicker
would actually support Double
, try it out!
Here's the Fragment extension you need to copy & paste:
fun Fragment.showNumberPickerDialog(
title: String,
value: Double,
range: ClosedRange<Double>,
stepSize: Double,
formatToString: (Double) -> String,
valueChooseAction: (Double) -> Unit
) {
val numberPicker = NumberPicker(context).apply {
setFormatter { formatToString(it.toDouble() * stepSize) }
wrapSelectorWheel = false
minValue = (range.start / stepSize).toInt()
maxValue = (range.endInclusive / stepSize).toInt()
this.value = (value.toDouble() / stepSize).toInt()
// NOTE: workaround for a bug that rendered the selected value wrong until user scrolled, see also: https://stackoverflow.com/q/27343772/3451975
(NumberPicker::class.java.getDeclaredField("mInputText").apply { isAccessible = true }.get(this) as EditText).filters = emptyArray()
}
MaterialAlertDialogBuilder(context)
.setTitle(title)
.setView(numberPicker)
.setPositiveButton("OK") { _, _ -> valueChooseAction(numberPicker.value.toDouble() * stepSize) }
.setNeutralButton("Cancel") { _, _ -> /* do nothing, closes dialog automatically */ }
.show()
}
Now you can use it like this (in a Fragment
):
showNumberPickerDialog(
title = "Your Weight",
value = 75.0, // in kilograms
range = 10.0 .. 300.0,
stepSize = 0.1,
formatToString = { "$it kg" },
valueChooseAction = { saveNewWeight(it) }
)
Another solution is to combine two numberfields into one component. See the Money Picker Example. Its advantage is that you don't have to initialize all possible double values for your spinner.
You may also need to attach special digits formatting, like "00", "0123" or other, using java.lang.String.format()
function. Example is here.
Add Double Picker xml-layout:
<LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android" android:layout_width = "fill_parent" android:layout_height = "wrap_content" android:gravity = "center"> <NumberPicker android:id = "@+id/integer_picker" android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:layout_gravity = "center"/> <TextView android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:layout_gravity = "center" android:padding = "5dp" android:text = "@string/local_separator" android:textSize = "20sp"/> <NumberPicker android:id = "@+id/fraction_picker" android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:layout_gravity = "center"/> <TextView android:layout_width = "wrap_content" android:layout_height = "wrap_content" android:layout_gravity = "center" android:padding = "5dp" android:text = "@string/measure_unit_sign" android:textSize = "20sp"/> </LinearLayout>
Add custom Double Picker class:
import android.content.Context; import android.view.LayoutInflater; import android.widget.NumberPicker; /** * UI component for double (floating point) values. Can be used * for money and other measures. */ public class DoublePicker extends NumberPicker { private int decimals; private NumberPicker integerPicker; private NumberPicker fractionPicker; public DoublePicker( Context context) { super( context); LayoutInflater .from( context) .inflate( R.layout.double_picker, this); integerPicker = (NumberPicker) findViewById( R.id.integer_picker); fractionPicker = (NumberPicker) findViewById( R.id.fraction_picker); } public int getDecimals() { return decimals; } /** * Sets the amount of digits after separator. * * @param decimals Anount of decimals. */ public void setDecimals(final int decimals) { this.decimals = decimals; this.setFormatter(new DoublePicker.Formatter() { @Override public String format(int i) { return String.format( "%." + decimals + "f", i); } }); } public void setValue(double value) { integerPicker.setValue((int) value); fractionPicker.setValue( Integer.valueOf( String .valueOf(value) .split(".") [1])); } }
Use new Double Picker component in your activity xml:
<com.example.DoublePicker android:id ="@+id/double_picker" android:layout_width ="match_parent" android:layout_height ="wrap_content" />