Auf meinem Dialogfragment befindet sich eine blaue Linie, die ich nicht entfernen kann (ich weiß nicht einmal, warum sie überhaupt angezeigt wird. Weiß jemand, wie ich sie entfernen kann?

Ich habe es auf mehreren Geräten getestet und es funktioniert einwandfrei auf späteren Android-Versionen.

Mein Code:

    private void setupD,ialog() {
    final Dialog dialog = getDialog();
    final Window window = dialog.getWindow();

    window.setBackgroundDrawable(new ColorDrawable(0));
    window.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE);
    }

Layout

      <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tiktok="http://schemas.android.com/apk/res-auto"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@drawable/settings_bg">

    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true">

        <ImageView
            android:id="@+id/close_btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_margin="15dp"
            android:src="@drawable/pressable_close_btn"/>

        <com.cyscorpions.timekeeper.customviews.TKTextView
            android:id="@+id/settings_title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="@dimen/dp_40"
            android:text="@string/settings_allcaps"
            android:textColor="@color/timekeeper_blue"
            android:textSize="@dimen/sp_60"
            tiktok:useBoldFont="true"/>

        <com.cyscorpions.timekeeper.customviews.TKTextView
            android:id="@+id/account_name_instruction"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/settings_title"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="@dimen/dp_20"
            android:text="@string/subdomain_instruction"
            android:textColor="@color/gray"
            android:textSize="@dimen/sp_30"/>

        <RelativeLayout
            android:id="@+id/info_field"
            android:layout_width="wrap_content"
            android:layout_height="@dimen/dp_70"
            android:layout_alignLeft="@+id/submit_btn"
            android:layout_below="@id/account_name_instruction"
            android:layout_centerHorizontal="true"
            android:layout_marginLeft="2dp"
            android:layout_marginTop="@dimen/dp_20">

            <com.cyscorpions.timekeeper.customviews.TKAppCompatEditText
                android:id="@+id/subdomain_textfield"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerVertical="true"
                android:background="@drawable/text_field_bg"
                android:hint="@string/textfield_account_hint"
                android:inputType="text"
                android:textColor="@color/gray"
                android:textColorHint="@color/gray"
                android:textSize="@dimen/sp_20"
                tiktok:setTextFieldFont="@string/montserrat_reg"/>

            <com.cyscorpions.timekeeper.customviews.TKTextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerVertical="true"
                android:layout_toRightOf="@id/subdomain_textfield"
                android:text="@string/domain_suffix"
                android:textColor="@color/gray"
                android:textSize="@dimen/sp_25"/>
        </RelativeLayout>

        <RelativeLayout
            android:id="@+id/error_tooltip"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_below="@id/settings_title">

            <ImageView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="@drawable/error_tooltip"
                android:shadowColor="@color/black"/>

            <com.cyscorpions.timekeeper.customviews.TKTextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerHorizontal="true"
                android:layout_marginTop="@dimen/dp_20"
                android:text="@string/field_required"
                android:textColor="@color/white"
                android:textSize="@dimen/sp_30"/>
        </RelativeLayout>

        <com.cyscorpions.timekeeper.customviews.TKButton
            android:id="@id/submit_btn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/info_field"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="@dimen/dp_10"
            android:background="@drawable/pressable_submit_btn"
            android:text="@string/submit_allcaps"
            android:textColor="@color/white"
            android:textSize="@dimen/sp_30"
            tiktok:hasDarkerPressedState="true"
            tiktok:useDefaultDrawable="true"/>

    </RelativeLayout>

</RelativeLayout>