Android数据绑定:无法将属性注入" include"标签

时间:2016-12-14 22:01:18

标签: android android-layout android-databinding

我正在尝试创建可重复使用的布局included.xml,然后可以将其注入其他布局并通过标记属性进行自定义。这就是我所拥有的:

res/layout/parent.xml

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/com.myself.fancyapp"
    >

    <include layout="@layout/included"
            app:src123="@drawable/my_icon" />

</layout>

res/layout/included.xml

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    >
    <data>
        <variable name="src123" type="android.graphics.drawable.Drawable" />
    </data>

    <android.support.design.widget.FloatingActionButton
        android:src="@{src123}" />
</layout>

app/build.gradle

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

    dataBinding {
        enabled = true
    }
    ....
}

dependencies {
    compile 'com.android.support:appcompat-v7:23.1.1'
    compile 'com.android.support:design:23.1.1'
}

结果,我尝试注入的按钮根本不包含任何图像。

如果在parent.xml我将xmlns:app更改为res-auto,则app/build/intermediate/data-binding-layout-out/debug/layout/parent.xml中出现以下错误:

  

错误:(17)找不到属性&#39; src123&#39;在包中&#39; com.myself.fancyapp&#39;

有没有人知道为什么会这样,以及如何解决这个问题?感谢。

1 个答案:

答案 0 :(得分:3)

问题在于您没有对变量使用绑定语法:

<include layout="@layout/included"
        app:src123="@drawable/my_icon" />

应该是:

<include layout="@layout/included"
        app:src123="@{@drawable/my_icon}" />

不相关,但我不认为包含是允许作为布局的根元素。我相信你必须有一个关于包含的正常视图。

<?xml version="1.0" encoding="utf-8"?>
<layout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/com.myself.fancyapp"
    >

    <FrameLayout android:layout_width="match_parent"
                 android:layout_height="match_parent">
        <include layout="@layout/included"
                app:src123="@{@drawable/my_icon}" />
    </FrameLayout>
</layout>