<com.google.android.material.textfield.TextInputLayout
    android:hint="Hint"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/TextInputLayoutHint">

    <androidx.appcompat.widget.AppCompatEditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="text"
        android:maxLines="1"
        android:paddingTop="@dimen/_5sdp"
        android:paddingBottom="@dimen/_5sdp"
        android:textColor="#000000"
        android:textColorHint="#959aa6" />

</com.google.android.material.textfield.TextInputLayout>

res /价值/ styles.xml

<style name="TextInputLayoutHint" parent="">
    <item name="android:textColorHint">#545454</item>
    <item name="colorControlActivated">#2dbc99</item>
    <item name="android:textSize">11sp</item>
</style>

你应该换一下颜色

<style name="Base.Theme.DesignDemo" parent="Theme.AppCompat.Light.NoActionBar">
        <item name="colorPrimary">#673AB7</item>
        <item name="colorPrimaryDark">#512DA8</item>
        <item name="colorAccent">#FF4081</item>
        <item name="android:windowBackground">@color/window_background</item>
    </style>

你不需要使用android:theme="@style/TextInputLayoutTheme"来改变浮动标签的颜色，因为它会影响到整个主题的小TextView用作标签。相反，你可以使用app:hintTextAppearance="@style/TextInputLayout。HintText”:

<style name="TextInputLayout.HintText">
  <item name="android:textColor">?attr/colorPrimary</item>
  <item name="android:textSize">@dimen/text_tiny_size</item>
  ...
</style>

让我知道解决方案是否有效:-)

  <style name="AppTheme2" parent="AppTheme">
    <!-- Customize your theme here. -->
    <item name="colorControlNormal">#fff</item>
    <item name="colorControlActivated">#fff</item></style>    

将此添加到styles并将TextInputLayout Theam设置为App2，它将工作;)

因为你必须在主应用主题中添加colorControlNormal, colorControlActivated, colorControlHighLight三项:

<!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">

        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>

        <item name="colorControlActivated">@color/yellow_bright</item>
        <item name="colorControlNormal">@color/yellow_black</item>

    </style>

在最新版本的支持库(23.0.0+)中，TextInputLayout采用以下XML属性来编辑浮动标签颜色: