"layout_toEndOf" 定位不正确

Question

我想在 Button 左边显示一个 EditText。因此，我定义了以下 .xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    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"
        android:id="@+id/coordinator_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        tools:context="de.abelssoft.lowbatterywarner.DataActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/data_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="80dp"
        app:layout_anchor="@id/coordinator_layout"
        app:layout_anchorGravity="bottom"
        android:background="@color/light_grey">

        <EditText android:id="@+id/edit_message"
            android:background="@android:color/white"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:inputType="textCapSentences|textMultiLine"
            android:maxLength="2000"
            android:maxLines="4"
            android:hint="Nachricht schreiben..." />

        <Button
            android:id="@+id/button_folder"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toEndOf="@id/button_folder"
            android:background="@drawable/folder"
            android:onClick="onFolderClick"/>

    </RelativeLayout>
</android.support.design.widget.CoordinatorLayout>

虽然我使用的是 layout_toEndOf，但按钮位于屏幕中央。为什么会这样？这与相对布局是 CoordinatorLayout 的子布局这一事实有关吗？

Answer 1

将您的 RelativeLayout 更改为：

 <RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="80dp"
    app:layout_anchor="@id/coordinator_layout"
    app:layout_anchorGravity="bottom"
    android:background="@color/light_grey">

    <EditText android:id="@+id/edit_message"
        android:background="@android:color/white"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:inputType="textCapSentences|textMultiLine"
        android:maxLength="2000"
        android:maxLines="4"
        android:hint="Nachricht schreiben..." />

    <Button
        android:id="@+id/button_folder"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toEndOf="@id/edit_message"
        android:background="@drawable/folder"
        android:onClick="onFolderClick"/>

</RelativeLayout>

Answer 2

您在按钮主体中使用 layout_toEndOf 作为同一按钮的结尾：

<Button
            android:id="@+id/button_folder"
            android:layout_toEndOf="@id/button_folder"
/>

要么改变它，要么做这两个步骤

1- 将您的按钮右对齐：

android:layout_alignParentRight="true"

2- 将您的 editText 设置在它的左侧：

android:layout_toLeftOf="@+id/button_folder"

Answer 3

您给按钮的 ID 有误....只需复制下面的代码即可

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:id="@+id/coordinator_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    tools:context="de.abelssoft.lowbatterywarner.DataActivity">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/data_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="80dp"
        android:background="@color/light_grey"
        app:layout_anchor="@id/coordinator_layout"
        app:layout_anchorGravity="bottom">

        <EditText
            android:id="@+id/edit_message"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:hint="Nachricht schreiben..."
            android:inputType="textCapSentences|textMultiLine"
            android:maxLength="2000"
            android:maxLines="4" />

        <Button
            android:id="@+id/button_folder"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toEndOf="@id/edit_message"
            android:background="@drawable/folder"
            android:onClick="onFolderClick" />

    </RelativeLayout>
</android.support.design.widget.CoordinatorLayout>

"layout_toEndOf" 定位不正确

"layout_toEndOf" not positioning correctly

xml

android

position

android-layout