如何在底部使Button重叠CardView

Question

我正在创建一个显示公告的应用程序，我想添加一个登录信息。我正在尝试制作这个XML设计。我希望按钮在其底部和中心覆盖CardView。如果有必要，我将更改文件的根目录。

这是我的XML代码：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    android:background="#fff"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.crescendo.lldm.crescendo.A_Login">

    <RelativeLayout
        android:id="@+id/rl_one_login"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <View
            android:id="@+id/v_one_login"
            android:background="@drawable/gradient_background_one"
            android:layout_width="match_parent"
            android:layout_height="300dp" />

        <RelativeLayout
            android:layout_marginTop="90dp"
            android:id="@+id/rl_two_login"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:textStyle="bold"
                android:id="@+id/tv_one_login"
                android:textSize="32sp"
                android:textAlignment="center"
                android:textColor="@color/colorWhite"
                android:text="C R E S C E N D O"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

            <TextView
                android:layout_below="@+id/tv_one_login"
                android:textSize="15sp"
                android:textAlignment="center"
                android:textColor="@color/colorWhite"
                android:text="FOR THE USA MONUMENTAL CHOIR"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />

        </RelativeLayout>

    </RelativeLayout>

    <android.support.v7.widget.CardView
        app:cardUseCompatPadding="false"
        app:cardPreventCornerOverlap="false"
        android:id="@+id/cv_one_login"
        app:cardBackgroundColor="#fcfcfc"
        android:layout_marginTop="240dp"
        card_view:cardElevation="10dp"
        app:cardCornerRadius="10dp"
        android:elevation="10dp"
        android:layout_centerHorizontal="true"
        android:layout_width="360dp"
        android:layout_height="280dp">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">

        </RelativeLayout>

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

    <Button
        android:layout_marginTop="197dp"
        android:layout_below="@+id/rl_one_login"
        android:layout_centerHorizontal="true"
        android:elevation="15dp"
        app:backgroundTint="@color/colorPrimary"
        android:layout_width="250dp"
        android:layout_height="50dp" />

</RelativeLayout>

以下是我在XML设计中得到的结果，IMAGE2希望有一个解决方案。谢谢！

Answer 1

试试下面的布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:card_view="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">


    <View
        android:layout_width="match_parent"
        android:layout_height="250dp"
        android:background="@color/colorAccent" />

    <RelativeLayout
        android:id="@+id/rl_two_login"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="90dp">

        <TextView
            android:id="@+id/tv_one_login"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="C R E S C E N D O"
            android:textAlignment="center"
            android:textColor="#ffffff"
            android:textSize="32sp"
            android:textStyle="bold" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/tv_one_login"
            android:text="FOR THE USA MONUMENTAL CHOIR"
            android:textAlignment="center"
            android:textColor="#ffffff"
            android:textSize="15sp" />

    </RelativeLayout>

    <LinearLayout
        android:layout_marginTop="-50dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">


            <android.support.v7.widget.CardView
                android:id="@+id/cv_one_login"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_centerHorizontal="true"
                android:layout_marginTop="240dp"
                android:elevation="10dp"
                app:cardBackgroundColor="#fcfcfc"
                app:cardCornerRadius="10dp"
                app:cardElevation="10dp"
                app:cardPreventCornerOverlap="false"
                app:cardUseCompatPadding="true">

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

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:padding="10dp"
                        android:text="Nilu" />

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:padding="10dp"
                        android:text="Nilu" />

                    <TextView
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:padding="10dp"
                        android:text="Nilu" />


                </LinearLayout>

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

        <Button
            android:layout_width="250dp"
            android:layout_height="50dp"
            android:layout_below="@id/cv_one_login"
            android:layout_centerHorizontal="true"
            android:layout_gravity="center"
            android:layout_marginTop="-35dp"
            android:elevation="15dp" />


    </LinearLayout>

</RelativeLayout>

OUTPUT

Answer 2

试试这个

产量

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:card_view="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="#fff">

<RelativeLayout
    android:id="@+id/rl_one_login"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <View
        android:id="@+id/v_one_login"
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:background="#0000FF" />

    <RelativeLayout
        android:id="@+id/rl_two_login"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="90dp">

        <TextView
            android:id="@+id/tv_one_login"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="C R E S C E N D O"
            android:textAlignment="center"
            android:textColor="#FFFFFF"
            android:textSize="32sp"
            android:textStyle="bold" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/tv_one_login"
            android:text="FOR THE USA MONUMENTAL CHOIR"
            android:textAlignment="center"
            android:textColor="#FFFFFF"
            android:textSize="15sp" />

    </RelativeLayout>

</RelativeLayout>

<LinearLayout
    android:id="@+id/lin_card"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="150dp"
    android:visibility="visible">

    <android.support.v7.widget.CardView
        android:id="@+id/cv_one_login"
        android:layout_width="match_parent"
        android:layout_height="280dp"
        android:layout_centerHorizontal="true"
        android:layout_margin="15dp"
        android:elevation="10dp"
        app:cardBackgroundColor="#fcfcfc"
        app:cardCornerRadius="10dp"
        app:cardPreventCornerOverlap="false"
        app:cardUseCompatPadding="false"
        card_view:cardElevation="10dp">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">

        </RelativeLayout>

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

</LinearLayout>


<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginBottom="37dp"
    android:elevation="15dp"
    android:gravity="center">

    <Button
        android:id="@+id/button"
        android:layout_width="250dp"
        android:layout_height="50dp"
        android:background="@drawable/custom_circle"
        android:text="Login"
        android:textAllCaps="false"
        android:textColor="#fff" />
</LinearLayout>

custom_circle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <corners android:radius="50dp" />
    <solid android:color="@color/colorPrimary" />

</shape>

Answer 3

使用ConstraintLayout这个问题可以解决：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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="@android:color/white">

    <View
        android:id="@+id/view_blank"
        android:layout_width="match_parent"
        android:layout_height="260dp"
        android:background="@color/colorPrimary"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"/>

    <ImageView
        android:id="@+id/image_logo"
        android:layout_width="90dp"
        android:layout_height="90dp"
        android:layout_marginTop="80dp"
        android:src="@drawable/ic_action_facebook"
        android:tint="@android:color/white"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"/>


    <android.support.constraint.ConstraintLayout
        android:id="@+id/credentials_card"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_marginTop="20dp"
        android:padding="@dimen/spacing_mlarge"
        app:layout_constraintTop_toBottomOf="@+id/image_logo"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent">


        <android.support.v7.widget.CardView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="@dimen/spacing_medium"
            android:visibility="visible"
            app:cardUseCompatPadding="true"
            app:cardCornerRadius="6dp"
            app:cardElevation="5dp"
            tools:ignore="MissingConstraints">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:padding="@dimen/spacing_xmlarge">

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center_horizontal"
                    android:layout_marginBottom="25dp"
                    android:text="SIGN IN"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
                    android:textColor="@color/colorAccent"
                    android:textStyle="bold" />

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="USERNAME"
                    android:textAlignment="center"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Caption"
                    android:textColor="@color/colorPrimary" />

                <android.support.design.widget.TextInputEditText
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="text"
                    android:maxLength="50"
                    android:maxLines="1"
                    android:singleLine="true"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
                    android:textColor="@color/colorPrimary"
                    android:textStyle="bold"
                    android:theme="@style/EditText.Grey" />


                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="20dp"
                    android:text="PASSWORD"
                    android:textAlignment="center"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Caption"
                    android:textColor="@color/colorPrimary" />

                <android.support.design.widget.TextInputEditText
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="textPassword"
                    android:maxLength="50"
                    android:maxLines="1"
                    android:singleLine="true"
                    android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
                    android:textColor="@color/colorPrimary"
                    android:textStyle="bold"
                    android:theme="@style/EditText.Grey" />


            </LinearLayout>

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

    </android.support.constraint.ConstraintLayout>

    <Button
        android:id="@+id/sign_up"
        android:layout_width="match_parent"
        android:layout_height="57dp"
        android:layout_marginLeft="50dp"
        android:layout_marginRight="50dp"
        android:background="@drawable/btn_rounded_primary"
        android:text="S I G N  I N"
        android:textAllCaps="false"
        android:textColor="@android:color/white"
        android:textStyle="bold"
        app:layout_constraintBottom_toBottomOf="@+id/credentials_card"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"/>


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:clickable="true"
        android:layout_marginTop="20dp"
        android:text="FORGET PASSWORD"
        android:textAppearance="@style/Base.TextAppearance.AppCompat.Subhead"
        android:textColor="@color/grey_40"
        android:textStyle="bold"
        app:layout_constraintTop_toBottomOf="@+id/sign_up"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"/>


</android.support.constraint.ConstraintLayout>

这是btn_rounded_primary：

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true">

        <layer-list>
            <item android:bottom="4dp" android:left="4dp" android:right="4dp" android:top="4dp">
                <shape android:shape="rectangle">
                    <corners android:bottomLeftRadius="30dp" android:bottomRightRadius="30dp" android:radius="60dp" android:topLeftRadius="30dp" android:topRightRadius="30dp" />
                    <solid android:color="@color/colorPrimaryDark" />
                    <padding android:bottom="0dp" android:left="0dp" android:right="0dp" android:top="0dp" />
                    <size android:width="110dp" android:height="40dp" />
                </shape>
            </item>
        </layer-list>

    </item>
    <item android:state_focused="true">

        <layer-list>
            <item android:bottom="4dp" android:left="4dp" android:right="4dp" android:top="4dp">
                <shape android:shape="rectangle">
                    <corners android:bottomLeftRadius="30dp" android:bottomRightRadius="30dp" android:radius="60dp" android:topLeftRadius="30dp" android:topRightRadius="30dp" />
                    <solid android:color="@color/colorPrimaryDark" />
                    <padding android:bottom="0dp" android:left="0dp" android:right="0dp" android:top="0dp" />
                    <size android:width="110dp" android:height="40dp" />
                </shape>
            </item>
        </layer-list>

    </item>

    <item>

        <layer-list>
            <item android:bottom="4dp" android:left="4dp" android:right="4dp" android:top="4dp">
                <shape android:shape="rectangle">
                    <corners android:bottomLeftRadius="30dp" android:bottomRightRadius="30dp" android:radius="60dp" android:topLeftRadius="30dp" android:topRightRadius="30dp" />
                    <solid android:color="@color/colorPrimary" />
                    <padding android:bottom="0dp" android:left="0dp" android:right="0dp" android:top="0dp" />
                    <size android:width="110dp" android:height="40dp" />
                </shape>
            </item>
        </layer-list>

    </item>
</selector>

这是dimens.xml：

<!--genaral spacing-->
<dimen name="spacing_xsmall">2dp</dimen>
<dimen name="spacing_small">3dp</dimen>
<dimen name="spacing_medium">5dp</dimen>
<dimen name="spacing_xmedium">7dp</dimen>
<dimen name="spacing_middle">10dp</dimen>
<dimen name="spacing_large">15dp</dimen>
<dimen name="spacing_smlarge">18dp</dimen>
<dimen name="spacing_mlarge">20dp</dimen>
<dimen name="spacing_mxlarge">25dp</dimen>
<dimen name="spacing_xlarge">35dp</dimen>
<dimen name="spacing_xmlarge">40dp</dimen>
<dimen name="spacing_xxlarge">50dp</dimen>
<dimen name="spacing_xxxlarge">55dp</dimen>
<dimen name="appbar_padding_top">8dp</dimen>

colors.xml

<color name="grey_3">#f7f7f7</color>
<color name="grey_5">#f2f2f2</color>
<color name="grey_10">#e6e6e6</color>
<color name="grey_20">#cccccc</color>
<color name="grey_40">#999999</color>
<color name="grey_60">#666666</color>
<color name="grey_80">#37474F</color>
<color name="grey_90">#263238</color>

使用ConstraintLayout输出：

Answer 4

您可以使用Constraint Layout library和设计选项卡轻松完成此操作。

Sample photo

这是代码，但我在设计选项卡中完成了大部分工作。

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.v7.widget.CardView
        android:id="@+id/credentials_card"
        android:layout_width="150dp"
        android:layout_height="250dp"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.281">

        <android.support.constraint.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <EditText
                android:id="@+id/username_field"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginEnd="8dp"
                android:layout_marginStart="8dp"
                android:layout_marginTop="48dp"
                android:hint="Username"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintHorizontal_bias="0.511"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent" />

            <EditText
                android:id="@+id/passworld_field"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginBottom="8dp"
                android:layout_marginEnd="8dp"
                android:layout_marginStart="8dp"
                android:layout_marginTop="8dp"
                android:hint="Password"
                app:layout_constraintBottom_toBottomOf="parent"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/username_field" />

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

    <Button
        android:id="@+id/login_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:text="Login!"
        app:layout_constraintBottom_toBottomOf="@+id/credentials_card"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/credentials_card" />

</android.support.constraint.ConstraintLayout>

Answer 5

使用下面的代码根据按钮高度调整margintop。我将其设置为-25dp，因为它的高度为50dp

  <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout
        android:background="#fff"
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:context="com.crescendo.lldm.crescendo.A_Login">

        <RelativeLayout
            android:id="@+id/rl_one_login"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <View
                android:id="@+id/v_one_login"
                android:background="@drawable/gradient_background_one"
                android:layout_width="match_parent"
                android:layout_height="300dp" />

            <RelativeLayout
                android:layout_marginTop="90dp"
                android:id="@+id/rl_two_login"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">

                <TextView
                    android:textStyle="bold"
                    android:id="@+id/tv_one_login"
                    android:textSize="32sp"
                    android:textAlignment="center"
                    android:textColor="@color/colorWhite"
                    android:text="C R E S C E N D O"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content" />

                <TextView
                    android:layout_below="@+id/tv_one_login"
                    android:textSize="15sp"
                    android:textAlignment="center"
                    android:textColor="@color/colorWhite"
                    android:text="FOR THE USA MONUMENTAL CHOIR"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content" />

            </RelativeLayout>

        </RelativeLayout>

        <android.support.v7.widget.CardView
            app:cardUseCompatPadding="false"
            app:cardPreventCornerOverlap="false"
            android:id="@+id/cv_one_login"
            app:cardBackgroundColor="#fcfcfc"
            android:layout_marginTop="240dp"
            card_view:cardElevation="10dp"
            app:cardCornerRadius="10dp"
            android:elevation="10dp"
            android:layout_centerHorizontal="true"
            android:layout_width="360dp"
            android:layout_height="280dp">

            <RelativeLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent">

            </RelativeLayout>

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

        <Button        
            android:layout_below="@id/cv_one_login"
            android:layout_centerHorizontal="true"
            android:elevation="15dp"
            android:layout_marginTop="-25dp"
            app:backgroundTint="@color/colorPrimary"
            android:layout_width="250dp"
            android:layout_height="50dp" />

    </RelativeLayout>

Answer 6

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    <LinearLayout android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:orientation="vertical">
        <LinearLayout android:layout_width="match_parent"
                    android:layout_height="0dp"
                    android:background="@drawable/background_login"
                    android:layout_weight="1"
        android:layout_marginBottom="@dimen/margin_large"></LinearLayout>

        <RelativeLayout
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:orientation="vertical"
                android:layout_marginTop="-60dp"
                android:layout_weight="1"
        >


            <android.support.v7.widget.CardView
                    android:id="@+id/card_view"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:layout_marginLeft="@dimen/margin_large"
                    android:layout_marginRight="@dimen/margin_large"
                    android:layout_marginBottom="30dp"
                    android:background="@android:color/white"
                    card_view:cardCornerRadius="@dimen/margin_card_medium"
                    card_view:cardElevation="@dimen/margin_card_medium">

                <LinearLayout
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:orientation="vertical"
                        android:padding="@dimen/margin_medium_2">

                    <TextView android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:text="@string/login"
                            android:gravity="center"
                            android:textSize="@dimen/text_regular_3x"
                            android:textColor="@color/secondaryText"/>

                    <TextView android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:text="@string/email"
                            android:textSize="@dimen/text_small"
                            android:textColor="@color/colorBlue"
                            android:layout_marginTop="@dimen/margin_medium"/>

                    <EditText
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:id="@+id/ed_email"
                            android:textSize="@dimen/text_regular"
                            android:inputType="textEmailAddress"/>

                    <TextView android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:textSize="@dimen/text_small"
                            android:text="@string/password"
                            android:textColor="@color/colorBlue"
                            android:layout_marginTop="@dimen/margin_large"/>

                    <EditText
                            android:id="@+id/ed_password"
                            android:layout_width="match_parent"
                            android:layout_height="wrap_content"
                            android:textSize="@dimen/text_regular"
                            android:inputType="textPassword"/>



                        <CheckBox
                                android:layout_width="match_parent"
                                android:layout_height="wrap_content"
                                android:text="@string/show_password"
                                android:textSize="@dimen/text_small"
                                android:textColor="@color/secondaryText"
                                android:buttonTint="@color/secondaryText"
                                android:checked="true"
                        />


                </LinearLayout>

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

        </RelativeLayout>
        <Button
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_gravity="center"
        android:layout_marginTop="-55dp"
        android:elevation="15dp"
        android:text="Log In"
        android:textColor="@color/colorWhite"
        android:layout_alignParentBottom="true"
        android:background="@drawable/shapesignup"

        />

    </LinearLayout>
    <TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|center"
    android:text="FORGOT PASSWORD?"
    android:layout_centerHorizontal="true"
    android:layout_alignParentBottom="true"
    android:textColor="@color/secondaryText"
    android:textSize="@dimen/text_small"
    android:layout_margin="@dimen/margin_large"
    />
</android.support.design.widget.CoordinatorLayout>    

OutPut

这里是background_login

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <gradient
            android:angle="225"
            android:startColor="@color/colorBlue"
            android:endColor="#21d6d3" />
</shape>