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public class ObservableFloat
extends BaseObservable implements Parcelable, Serializable

   ↳ android.databinding.BaseObservable
     ↳ android.databinding.ObservableFloat

An observable class that holds a primitive float.

Observable field classes may be used instead of creating an Observable object. It can also create a calculated field, depending on other fields:

public class MyDataObject {
     public final ObservableFloat temperatureC = new ObservableFloat();
     public final ObservableFloat temperatureF = new ObservableFloat(temperatureC) {
         public float get() { return (temperatureC.get() * 9 / 5) + 32; }
Fields of this type should be declared final because bindings only detect changes in the field's value, not of the field itself.

This class is parcelable and serializable but callbacks are ignored when the object is parcelled / serialized. Unless you add custom callbacks, this will not be an issue because data binding framework always re-registers callbacks when the view is bound. A parceled ObservableField will lose its dependencies.


Inherited constants

From interface android.os.Parcelable


public static final Creator<ObservableFloat> CREATOR

Public constructors

ObservableFloat(float value)

Creates an ObservableFloat with the given initial value.


Creates an ObservableFloat with the initial value of 0f.

ObservableFloat(Observable... dependencies)

Creates an ObservableFloat that depends on dependencies.

Public methods

int describeContents()
float get()
void set(float value)

Set the stored value.

void writeToParcel(Parcel dest, int flags)

Inherited methods

From class android.databinding.BaseObservable
From class java.lang.Object
From interface android.databinding.Observable
From interface android.os.Parcelable



Creator<ObservableFloat> CREATOR

Public constructors


ObservableFloat (float value)

Creates an ObservableFloat with the given initial value.

value float: the initial value for the ObservableFloat


ObservableFloat ()

Creates an ObservableFloat with the initial value of 0f.


ObservableFloat (Observable... dependencies)

Creates an ObservableFloat that depends on dependencies. Typically, ObservableFields are passed as dependencies. When any dependency notifies changes, this ObservableFloat also notifies a change.

dependencies Observable: The Observables that this ObservableFloat depends on.

Public methods


int describeContents ()



float get ()

float the stored value.


void set (float value)

Set the stored value.

value float: The new value


void writeToParcel (Parcel dest, 
                int flags)

dest Parcel

flags int

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