Question

这是我的布局文件。

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context=".ActivityMain">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/toolbarLayer"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

    <ListView
        android:id="@+id/users"
        android:layout_marginTop="40dp"
        android:padding="20dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/toolbarLayer"
        android:layout_above="@+id/button_add_new_user"
        />

    <Button
        android:id="@+id/button_add_new_user"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add New User"
        android:layout_alignParentBottom="true"
        />


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

我想在活动底部显示一个按钮。但上面的代码没有显示按钮。

任何人都可以帮我解决这里的问题吗？

Answer 1

这将正确对齐您的相对布局，包括工具栏下方的Listview（上方按钮）和按钮（父级底部对齐）。

<?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:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fitsSystemWindows="true"
      >

        <android.support.design.widget.AppBarLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/toolbarLayer"
            android:theme="@style/AppTheme.AppBarOverlay">

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                android:background="?attr/colorPrimary"
                app:popupTheme="@style/AppTheme.PopupOverlay" />

        </android.support.design.widget.AppBarLayout>
        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@+id/toolbarLayer"
            android:layout_marginTop="?attr/actionBarSize"
            >
            <ListView
                android:id="@+id/users"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_above="@+id/button_add_new_user"
                />

            <Button
                android:id="@+id/button_add_new_user"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="Add New User"
                android:layout_alignParentBottom="true"
                />
        </RelativeLayout>



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

Answer 2

将listview和按钮包裹在这样的relativelayout中：

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context=".ActivityMain">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/toolbarLayer"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>
<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <ListView
        android:id="@+id/users"

        android:layout_marginTop="40dp"
        android:padding="20dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/toolbarLayer"
        android:layout_above="@+id/button_add_new_user"
        />

    <Button
        android:id="@+id/button_add_new_user"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add New User"
        android:layout_alignParentBottom="true"
        />
</RelativeLayout>



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

现在应该可以了。

Answer 3

require(ggmap)

map.background <- get_map(c(lon = -122, lat = 47.5), map = "toner-background")
map.lines <- get_map(c(lon = -122, lat = 47.5), map = "toner-lines")
map.labels <- get_map(c(lon = -122, lat = 47.5), map = "toner-labels")

set.seed(127)
df <- data.frame(lon = rnorm(25, mean = -122.2, sd = 0.2),
                 lat = rnorm(25, mean = 47.5, sd = 0.1),
                 size = rnorm(25, mean = 15, sd = 5))

ggmap(map.background) +
  geom_point(data = df,
             aes(x = lon, y = lat, size = size),
             color = "blue", alpha = 0.8) + 
  scale_size_identity(guide = "none") + 
  inset_ggmap(map.lines) + 
  inset_ggmap(map.labels)

应用程式：popupTheme =＆＃34; @风格/ AppTheme.PopupOverlay＆＃34; /＆GT;

<android.support.design.widget.AppBarLayout
    android:id="@+id/toolbarLayer"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/AppTheme.AppBarOverlay">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"

Answer 4

使用此代码..

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/toolbarLayer">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

</android.support.design.widget.AppBarLayout>
<RelativeLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@+id/toolbarLayer"
    android:layout_marginTop="?attr/actionBarSize"
    >
    <ListView
        android:id="@+id/users"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_above="@+id/button_add_new_user"
        />

    <Button
        android:id="@+id/button_add_new_user"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Add New User"
        android:layout_alignParentBottom="true"
        />
</RelativeLayout>

按钮未显示在布局文件android中

4 个答案: