跳转到相应内容

最常访问

最近访问

navigation

ObservableDouble

public class ObservableDouble
extends BaseObservable implements Parcelable, Serializable

java.lang.Object
   ↳ android.databinding.BaseObservable
     ↳ android.databinding.ObservableDouble


An observable class that holds a primitive double. It can also create a calculated field, depending on other fields:

Observable field classes may be used instead of creating an Observable object:

public class MyDataObject {
     public final ObservableDouble temperatureC = new ObservableDouble();
     public final ObservableDouble temperatureF = new ObservableDouble(temperatureC) {
         @Override
         public double 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 ObservableByte will lose its dependencies.

Summary

Inherited constants

From interface android.os.Parcelable

Fields

public static final Creator<ObservableDouble> CREATOR

Public constructors

ObservableDouble(double value)

Creates an ObservableDouble with the given initial value.

ObservableDouble()

Creates an ObservableDouble with the initial value of 0.

ObservableDouble(Observable... dependencies)

Creates an ObservableDouble that depends on dependencies.

Public methods

int describeContents()
double get()
void set(double 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

Fields

CREATOR

Creator<ObservableDouble> CREATOR

Public constructors

ObservableDouble

ObservableDouble (double value)

Creates an ObservableDouble with the given initial value.

Parameters
value double: the initial value for the ObservableDouble

ObservableDouble

ObservableDouble ()

Creates an ObservableDouble with the initial value of 0.

ObservableDouble

ObservableDouble (Observable... dependencies)

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

Parameters
dependencies Observable: The Observables that this ObservableDouble depends on.

Public methods

describeContents

int describeContents ()

Returns
int

get

double get ()

Returns
double the stored value.

set

void set (double value)

Set the stored value.

Parameters
value double: The new value

writeToParcel

void writeToParcel (Parcel dest, 
                int flags)

Parameters
dest Parcel

flags int

此网站会使用 Cookie 来存储您在此网站上指定的语言和显示选项偏好设置。

获取最新的 Android Developers 资讯和提示,助您在 Google Play 上取得成功。

* 必填字段

成功!

在微信上关注 Google Developers

要以浏览此网站吗?

您请求访问的是网页,但是您为此网站设置的语言偏好为

要更改您的语言偏好设置并以浏览此网站吗?如果以后您想要更改语言偏好设置,请使用每个页面底部的语言菜单。

该类需要 或更高的 API 级别

此文档已被隐藏,因为您为该文档选择的 API 级别是 。您可以使用左侧导航栏上方的选择器来更改文档的 API 级别。

要详细了解如何根据您的应用需求指定 API 级别,请参阅支持不同平台版本

Take a short survey?
Help us improve the Android developer experience. (April 2018 — Developer Survey)