Android 如何在线性布局的顶部绘制边框
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How to draw a border at top of the linear layout
提问by n179911
I have followed the example in for the gradient dividers: http://www.connorgarvey.com/blog/?p=34
我遵循了梯度分隔符的示例：http: //www.connorgarvey.com/blog/?p= 34
I have tried to draw a horizontal line at the BOTTOM of my linear layout.
我试图在我的线性布局的底部画一条水平线。
Here is my linear layout file:
这是我的线性布局文件：
<LinearLayout android:id="@+id/test" android:layout_width="fill_parent"
android:layout_height="wrap_content>
<ImageView android:id="@+id/icon1"
android:layout_width="32dip"
android:layout_height="32dip"
/>
And I did add
我确实添加了
<View
android:background="@drawable/black_white_gradient"
android:layout_width="fill_parent"
android:layout_height="1dp"
android:layout_above="@id/test"
/>
But i don't see any line at the top of the LinearLayout. And when I go to Hierarchy View and see he View (for the hort separator), the getWidth() is 0 while getHeight() is 1.
但是我在 LinearLayout 的顶部没有看到任何行。当我转到层次结构视图并看到他的视图（用于 hort 分隔符）时，getWidth() 为 0，而 getHeight() 为 1。
Can you please tell me what am I missing?
你能告诉我我错过了什么吗？
Thank you.
谢谢你。
采纳答案by hwii77
I think the orientation might be missing in the parent linearlayout view;
我认为父线性布局视图中可能缺少方向；
<LinearLayout android:orientation="vertical"
Or if you use RelativeLayout instead of LinearLayout, you can set 's layout_alignParentBottom;
或者，如果您使用 RelativeLayout 而不是 LinearLayout，则可以设置 's layout_alignParentBottom;
<View android:layout_alignParentBottom="true"
回答by 1HaKr
With the code you posted ,its perfectly fine.But the fact that the size is 1dpmay not be showing it . increase the size or as you want only a line use this default line drawable from android
使用您发布的代码，它完全1dp没问题。但尺寸的事实可能没有显示出来。增加大小或者你只想要一条线，使用这个默认的可从 android 绘制的线
android:background="@android:drawable/divider_horizontal_bright"
// this for white background only
I hope this will help you get what you want
我希望这会帮助你得到你想要的
回答by bdhac
It will not be visible if the height is 1dp. Try 2dp instead:
如果高度为 1dp，它将不可见。改为尝试 2dp：
<View
android:background="@drawable/black_white_gradient"
android:layout_width="fill_parent"
android:layout_height="2dp"
android:layout_above="@id/test"
/>
<View
android:background="@drawable/black_white_gradient"
android:layout_width="fill_parent"
android:layout_height="2dp"
android:layout_above="@id/test"
/>
回答by Ronald
The black border is only shown if the size is at least 2dp. Try removing the border, and set the solid color to black:
仅当尺寸至少为 2dp 时才会显示黑色边框。尝试移除边框，并将纯色设置为黑色：
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="#000" />
</shape>
Than you can use a height of 1dp again.
比你可以再次使用 1dp 的高度。
