// activity_main.xml
<android.support.v7.widget.AppCompatEditText
    android:id="@+id/edit_text"
    style="@style/EditTextStyle"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="ヒント"
    app:theme="@style/EditTextStyle" />

// styles.xml
<style name="EditTextStyle" parent="Widget.AppCompat.EditText">
    <item name="colorControlNormal">@color/amber500</item>
    <item name="colorControlActivated">@color/pink500</item>
    <item name="android:textCursorDrawable">@color/indigo500</item>
    <item name="android:textColor">@color/orange500</item>
    <item name="android:textColorHint">@color/teal500</item>
    <item name="android:textColorHighlight">@color/purple500</item>
</style>

// edit_text_material.xml
<inset xmlns:android="http://schemas.android.com/apk/res/android"
  android:inset="@dimen/control_inset_material">
  <ripple android:color="?attr/colorControlActivated">
    <item>
      <selector>
        <item android:state_enabled="false">
          <nine-patch android:src="@drawable/textfield_default_mtrl_alpha"
            android:tint="?attr/colorControlNormal"
            android:alpha="?attr/disabledAlpha" />
        </item>
        <item>
          <nine-patch android:src="@drawable/textfield_default_mtrl_alpha"
            android:tint="?attr/colorControlNormal" />
        </item>
      </selector>
    </item>
    <item android:id="@+id/mask" android:drawable="@drawable/textfield_activated_mtrl_alpha" />
  </ripple>
</inset>

// TypedArray#getDrawable
@Nullable
public Drawable getDrawable(int index) {
  if (mRecycled) {
    throw new RuntimeException("Cannot make calls to a recycled instance!");
  }

  final TypedValue value = mValue;
  if (getValueAt(index*AssetManager.STYLE_NUM_ENTRIES, value)) {
    if (value.type == TypedValue.TYPE_ATTRIBUTE) {
      throw new UnsupportedOperationException(
          "Failed to resolve attribute at index " + index + ": " + value);
    }
    return mResources.loadDrawable(value, value.resourceId, mTheme);
  }
  return null;
}

// AppCompatViewInflater
public final View createView(View parent, final String name, @NonNull Context context,
    @NonNull AttributeSet attrs, boolean inheritContext,
    boolean readAndroidTheme, boolean readAppTheme) {
  ...
  if (readAndroidTheme || readAppTheme) {
    // We then apply the theme on the context, if specified
    context = themifyContext(context, attrs, readAndroidTheme, readAppTheme);
  }
  ...
    view = new AppCompatEditText(context, attrs);
  ...
}

private static Context themifyContext(Context context, AttributeSet attrs,
    boolean useAndroidTheme, boolean useAppTheme) {
  final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.View, 0, 0);
  int themeId = 0;
  if (useAndroidTheme) {
    // First try reading android:theme if enabled
    themeId = a.getResourceId(R.styleable.View_android_theme, 0);
  }
  if (useAppTheme && themeId == 0) {
    // ...if that didn't work, try reading app:theme (for legacy reasons) if enabled
    themeId = a.getResourceId(R.styleable.View_theme, 0);

    if (themeId != 0) {
      Log.i(LOG_TAG, "app:theme is now deprecated. "
          + "Please move to using android:theme instead.");
    }
  }
  a.recycle();

  if (themeId != 0 && (!(context instanceof ContextThemeWrapper)
      || ((ContextThemeWrapper) context).getThemeResId() != themeId)) {
    // If the context isn't a ContextThemeWrapper, or it is but does not have
    // the same theme as we need, wrap it in a new wrapper
    context = new ContextThemeWrapper(context, themeId);
  }
  return context;
}