Solution 1:

Define android:textColorHint in your application theme:

<style name="AppTheme" parent="Theme.AppCompat.NoActionBar">
    <item name="colorPrimary">@color/primary</item>
    <item name="colorPrimaryDark">@color/primary_dark</item>
    <item name="colorAccent">@color/accent</item>

    <item name="android:textColorHint">@color/secondary_text</item>
</style>

Source

Solution 2:

Create custom style in style.xml

<style name="EditTextHint" parent="TextAppearance.AppCompat">
    <item name="colorAccent">@android:color/white</item>
    <item name="android:textColorHint">@color/BackgroundtWhiteColor</item>
    <item name="colorControlNormal">@color/BackgroundtWhiteColor</item>
    <item name="colorControlActivated">@color/your color</item>
    <item name="colorControlHighlight">@color/BackgroundtWhiteColor</item>
</style>

Then in your layout xml file, add theme attribute as below

 <android.support.design.widget.TextInputLayout
            android:theme="@style/EditTextHint"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

      <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

</android.support.design.widget.TextInputLayout>

hope this works

Solution 3:

Add textColorHint property to your edit text

android:textColorHint="#F6F6F6"

or whichever color you want