安卓数据绑定layout_width和layout_height
2022-09-01 06:20:11
我需要能够动态设置EditText的高度属性。我正在对整个应用中的其他属性使用数据绑定,因此我希望能够使用数据绑定来控制元素的高度。以下是我的xml的精简版本:
<?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="loginVM" type="com.testing.stuff.ViewModels.LoginViewModel" />
</data>
<EditText android:inputType="number"
android:id="@+id/txtVerificationCode"
android:layout_height="@{loginVM.compact ? @dimen/verificationHeightCompact : @dimen/verificationHeightFull}"
android:layout_width="match_parent"
android:paddingRight="16dp"
android:paddingLeft="16dp"
android:focusable="true"
android:focusableInTouchMode="true"
android:layout_marginLeft="10dp"
android:alpha="@{loginVM.verificationOpacity}"
android:layout_marginStart="10dp"
android:textAlignment="center"
android:visibility="visible"
android:hint="Enter verificationCode"
android:text="@{loginVM.verificationCode}" />
</layout>
这是我的视图模型的精简版本:
public class LoginViewModel extends BaseObservable {
public final ObservableField<String> verificationCode;
public final ObservableField<Boolean> compact;
@Bindable
public String getVerificationCode() {
if (this.verificationCode == null) {
return "";
} else {
return this.verificationCode.get();
}
}
public void setVerificationCode(String verificationCode) {
this.verificationCode.set(verificationCode);
invalidateProperties();
}
@Bindable
public Boolean getCompact(){return this.compact.get();}
public void setCompact(Boolean value)
{
this.compact.set(value);
this.invalidateProperties();
}
@BindingAdapter("android:layout_height")
public static void setLayoutHeight(EditText view, float height)
{
ViewGroup.LayoutParams layoutParams = view.getLayoutParams();
layoutParams.height = (int)height;
view.setLayoutParams(layoutParams);
}
public LoginViewModel(Context ctx) {
verificationCode = new ObservableField();
compact = new ObservableField();
}
尺寸位于 dimens.xml 文件中。我正在修改视图模型中的属性。但是,当我启动应用程序时,我在启动后立即收到以下错误(绑定适配器未在调试时触发)。屏幕上还有其他几个元素,但是当发生特定操作时,我需要更改高度的这个元素:
FATAL EXCEPTION: main
Process: com.testing.stuff, PID: 32752
java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.testing.stuff/com.testing.stuff.Login}:
java.lang.RuntimeException: Binary XML file line #69: You must supply
a layout_height attribute.
Caused by: java.lang.RuntimeException: Binary XML file line #69: You
must supply a layout_height attribute.
关于这个问题,SO上有一些帖子,但没有明确的答案,或者这种方法不起作用。当然,这是一个常见的实现。提前感谢您的帮助。