問題描述

自從更新到 Android Studio 3.2.0 我面臨以下問題:

Since the update to Android Studio 3.2.0 I face the following issue:

任務:mobile:dataBindingGenBaseClassesDebug"執行失敗.

Execution failed for task ':mobile:dataBindingGenBaseClassesDebug'.

>無法猜測 com.ACME.database.model.Order

> couldn't make a guess for com.ACME.database.model.Order

也看到了這個答案，提示包名必須以小寫字母開頭".

also seen this answer, which hints for that "package-names must start with a lower-case letter".

...看起來很像，好像這個 variable 賦值是原因:

... it seems alike, as if this variable assignment would be the cause:

<data class=".databinding.OrderFragmentBinding">
    <variable name="order" type="com.ACME.database.model.Order"/>
    ...
</data>

找到:用于綁定類的新數據綁定編譯器，這并不能解釋行為的變化.

found: New data binding compiler for binding classes, which does not explain the change in behavior.

問:這樣的分配是否也受到該命名約定的影響?我的意思是，是否有任何機會(除了更改大寫包名稱)使數據綁定 v2 猜測"?鍛煉了嗎?

Q: are such assignments also affected by that naming convention? I mean, is there any chance (beside changing the uppercase package-name) to make that data-binding v2 "guess" work out?

推薦答案

gradle.properties 中的這些設置確實啟用了 androidx 數據綁定編譯器:

these settings in the gradle.properties do enable the androidx data-binding compiler:

android.databinding.enableV2 = false
android.enableExperimentalFeatureDatabinding = true

通過獲取的包可以看到:

one can see that by the fetched package:

Download https://dl.google.com/dl/android/maven2/androidx/databinding/databinding-compiler/3.2.0/databinding-compiler-3.2.0.pom
Download https://dl.google.com/dl/android/maven2/androidx/databinding/databinding-compiler/3.2.0/databinding-compiler-3.2.0.jar

它抱怨:

WARNING: The option setting 'android.databinding.enableV2=false' is experimental and unsupported.
The current default is 'true'

WARNING: The option setting 'android.enableExperimentalFeatureDatabinding=true' is experimental and unsupported.
The current default is 'false'

很可能需要 androidx.fragment.app.Fragment 而不是 android.support.v4.app.Fragment，以便數據綁定 Fragment 使用默認的 v2 數據綁定編譯器.這也只是一個臨時解決方案 - 但仍然比恢復到 v1 數據綁定編譯器要好.

most likely androidx.fragment.app.Fragment instead of android.support.v4.app.Fragment would be required, in order to data-bind a Fragment with the default v2 data-binding compiler. this is also just a temporary solution - but still better than to revert to the v1 data-binding compiler.

更新:

由于 com.android.tools.build:gradle:3.5.0 上述解決方法不再起作用；必須重構 XML 文件.在不將任何 class="" 屬性添加到 <data/> 標記中并且將此標記添加到任何現有 <layout> 時效果最佳; 標簽.數據綁定 <include> 標記上的重復 id 也可能會阻止生成(必須在 < 上設置 id;include> 標簽，不在包含的布局中).

Since com.android.tools.build:gradle:3.5.0 the above workaround does not work anymore; One has to refactor the XML files. It works best when not adding any class="" attribute into the <data /> tag - and also adding this tag into any existing <layout> tag. Duplicate id on data-bound <include> tags may also prevent the generation (the id has to be set on the <include> tag, not in the included layout).

這篇關于數據綁定因“無法猜測"而失敗的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！