在LinearLayout之上的Android Imageview

Question

我想在linearlayout上显示图像

我尝试将它包装在Framelayout和Relative布局中，但它似乎不起作用。

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


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

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:src="@drawable/cricle" />

    </RelativeLayout>           


    <LinearLayout
        android:layout_width="match_parent"
        android:orientation="vertical"
        android:padding="20dp"
        android:background="@color/blue"
        android:layout_height="wrap_content">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textStyle="bold"
            android:gravity="center"/>



    </LinearLayout>

</FrameLayout>

Answer 1

您可以使用ConstraintLayout。您必须在LinearLayout的顶部添加一个约束，具体取决于您在那里的其他内容。

<?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">

    <LinearLayout
        android:id="@+id/linear_layout"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:layout_marginBottom="8dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:background="#ffffff80"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

    </LinearLayout>

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="128dp"
        android:layout_height="128dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:src="@drawable/your_drawable"
        app:layout_constraintBottom_toTopOf="@id/linear_layout"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="@id/linear_layout" />

</android.support.constraint.ConstraintLayout>

Answer 2

尝试使用match_parent和layout_marginTop

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

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#aaaaaa"
        android:orientation="vertical"
        android:padding="20dp"
        android:layout_marginTop="70dp" >

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textStyle="bold"
            android:gravity="center"
            />
    </LinearLayout>

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

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentRight="true"
            android:layout_gravity="center_horizontal"
            android:src="@drawable/circle" />

    </RelativeLayout> 

</FrameLayout>

Answer 3

使您的相对布局宽度match_parent并为线性布局设置边距顶部

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


<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="50dp"
    android:background="@color/blue"
    android:orientation="vertical"
    android:padding="20dp">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textStyle="bold"/>


</LinearLayout>

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

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:src="@drawable/cricle"/>

</RelativeLayout>