我在wiz高度问题中无法在LinearLayout中使用

Question

我有一个问题，在LinearLayout中无法正常工作。 我想做这样的海拔，或者我不知道该怎么做

但是在设备中，没有高程或阴影

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<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/white"
    android:fillViewport="true"
    tools:context=".LoginActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="300dp"
            android:background="@drawable/bg_edited"
            android:orientation="vertical">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="@color/scrollbarbg"
                android:orientation="vertical"
                android:padding="10dp">

                <TextView
                    android:id="@+id/scrollingtext"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:background="@drawable/scrollabletextviewbg"
                    android:ellipsize="marquee"
                    android:focusable="true"
                    android:focusableInTouchMode="true"
                    android:gravity="center"
                    android:marqueeRepeatLimit="marquee_forever"
                    android:scrollHorizontally="true"
                    android:singleLine="true"
                    android:text="وَتَعَاوَنُوا عَلَى الْبِرِّ وَالتَّقْوَىٰ ۖ وَلَا تَعَاوَنُوا عَلَى الْإِثْمِ وَالْعُدْوَانِ ۚ وَاتَّقُوا اللَّهَ ۖ.com/"
                    android:textColor="@color/white"
                    android:textDirection="anyRtl"
                    android:textSize="20sp" />
                />
            </LinearLayout>

        </LinearLayout>

        <android.support.v7.widget.CardView
            android:layout_width="match_parent"
            android:layout_height="300dp"
            android:layout_marginLeft="30dp"
            android:layout_marginRight="30dp"
            android:layout_marginTop="-90dp"
            android:background="@color/white"
            app:cardCornerRadius="2dp"
            app:cardElevation="10dp">


            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginLeft="20dp"
                android:layout_marginRight="20dp"
                android:layout_marginTop="100dp"
                android:background="@color/white"
                android:orientation="horizontal"
                app:elevation="20dp">

                <ImageView
                    android:layout_width="20dp"
                    android:layout_height="20dp"
                    android:layout_marginTop="10dp"
                    android:src="@drawable/username" />

                <EditText
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:background="@null"
                    android:hint="@string/loginhintname"
                    android:padding="10dp" />
            </LinearLayout>


        </android.support.v7.widget.CardView>

    </LinearLayout>
</ScrollView>