Android数据绑定文档建议您可以在文本是视图模型的属性时有条件地设置文本.例如

android:text="@{user.displayName != null ? user.displayName : user.lastName}"

但有没有办法从strings.xml中设置文本而不是在我的视图模型中添加它？我想要这样的东西 –

android:text="@{viewmodel.expanded ? @string/collapse : @string/expand}"

XML看起来有点像这样：

<?xml version="1.0" encoding="UTF-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:bind="http://schemas.android.com/apk/res-auto">
   <data class="TravellerInfoBinding">
      <import type="android.view.View" />
      <variable name="viewmodel" type="com.myproject.viewmodel.TravellerInfoviewmodel" />

   </data>
   <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal">
      <ImageView android:layout_width="wrap_content" 
        android:layout_height="wrap_content" 
        android:layout_gravity="center_vertical"
        android:src="@drawable/expandable_arrow_blue" />

      <TextView style="@style/primary_pair_element_value" 
        android:layout_width="wrap_content"   
        android:layout_height="wrap_content" 
        android:text="@{viewmodel.expanded ? @string/taxes_fees_detail : @string/hide_taxes_fees_detail}"
        android:textSize="12sp" />

   </LinearLayout>
</layout>

这是我的视图模型 –

package com.myproject.viewmodel;

imports...

public class TravellerInfoviewmodel extends BaSEObservable {

  @Bindable
  private final TaxDetailsviewmodel taxDetailsviewmodel;

  @Bindable
  private boolean expanded;

  Constructor....

  public boolean isExpanded() {
    return expanded;
  }

  public void setExpanded(boolean expanded) {
    this.expanded = expanded;
    notifyPropertyChanged(BR.expanded);
  }

  public void toggleExpanded() {
    setExpanded(!expanded);
  }

}