数据绑定 - safeUnbox 警告 [英] data binding - safeUnbox warning

问题描述

在我将 AS gradle 版本升级到 2.3.0 后，数据绑定遇到警告:

after i upgrade AS gradle version to 2.3.0, data binding encounter a warning :

警告:selectMap[index] 是一个装箱字段，但需要取消装箱才能执行 selectMap[index] ?@android:color/white : @android:color/transparent.这可能会导致 NPE，因此数据绑定会安全地将其拆箱.您可以更改表达式并使用 safeUnbox() 显式包装 selectMap[index] 以防止警告

Warning:selectMap[index] is a boxed field but needs to be un-boxed to execute selectMap[index] ? @android:color/white : @android:color/transparent. This may cause NPE so Data Binding will safely unbox it. You can change the expression and explicitly wrap selectMap[index] with safeUnbox() to prevent the warning

selectMap 是一个 ObservableMap，然后我搜索了这个警告，但只有很少的讨论并且没有修复它

selectMap is an ObservableMap, then i search this warning but got just few discussions and did not fix it

Android Studio 2.3.0-alpha1:数据绑定 + int 拆箱导致编译错误

数据绑定 - API 15-18 上的数据对象为空

我按照链接中的方法，将 selectMap[index] 修改为 safeUnbox(selectMap[index]) 但出现语法错误.

I follow the way in the links, modify selectMap[index] to safeUnbox(selectMap[index]) but got syntax error.

那么有人知道如何解决这个警告吗?

So anyone know how to fix this warning?

这是xml文件代码

<?xml version="1.0" encoding="utf-8"?>

<data class="SupportCountryViewHolderBinding">

    <variable
        name="viewModel"
        type="com.goodarc.care_about.activity.account.support_country.SupportCountryHolderViewModel" />

    <variable
        name="dataSource"
        type="com.goodarc.care_about.module.assets_file.SupportCountry" />

    <variable
        name="selectMap"
        type="android.databinding.ObservableMap&lt;Integer, Boolean&gt;" />

    <variable
        name="index"
        type="int" />
</data>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@{selectMap[index] ? @android:color/white : @android:color/transparent}"
    android:onClick="@{(v) -> viewModel.onItemSelectListener(selectMap, index)}"
    android:orientation="vertical"
    android:padding="20dp">

    <TextView
        style="@style/TitleLabel2"
        android:layout_gravity="center_vertical|start"
        android:text="@{dataSource.display}"
        android:textColor="@{selectMap[index] ? @android:color/black : @android:color/white}"
        tools:text="Taiwan (+886)" />
</LinearLayout>

构建成功，但出现警告(我在上面).

Build is succeed, but warning come out(i past above).

推荐答案

我有同样的警告，就我而言，将变量声明从 Boolean 类型更改为 boolean 类型解决问题:

I had the same warning, in my case changing the variable declaration from Boolean type to boolean type solve the problem:

来自:

<variable
        name="readOnly"
        type="Boolean" />

致:

<variable
        name="readOnly"
        type="boolean" />

所以，也许你可以试试:

So, maybe you can try with:

<variable
    name="selectMap"
    type="android.databinding.ObservableMap&lt;Integer, boolean&gt;" />

这篇关于数据绑定 - safeUnbox 警告的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！