如何使一个形状与左上方圆角和左下方圆角？

It looks like a bug http://code.google.com/p/android/issues/detail?id=939.

Finally I have to write something like this:

 <stroke android:width="3dp"
android:color="#555555"
/>


<padding android:left="1dp"
android:top="1dp"
android:right="1dp"
android:bottom="1dp"
/>


<corners android:radius="1dp"
android:bottomRightRadius="2dp" android:bottomLeftRadius="0dp"
android:topLeftRadius="2dp" android:topRightRadius="0dp"/>

I have to specify android:bottomRightRadius="2dp" for left-bottom rounded corner (another bug here).

You can also use extremely small numbers for your radius'.

<corners
android:bottomRightRadius="0.1dp" android:bottomLeftRadius="2dp"
android:topLeftRadius="2dp" android:topRightRadius="0.1dp" />

While this question has been answered already (it's a bug that causes bottomLeftRadius and bottomRightRadius to be reversed), the bug has been fixed in android 3.1 (api level 12 - tested on the emulator).

So to make sure your drawables look correct on all platforms, you should put "corrected" versions of the drawables (i.e. where bottom left/right radii are actually correct in the xml) in the res/drawable-v12 folder of your app. This way all devices using an android version >= 12 will use the correct drawable files, while devices using older versions of android will use the "workaround" drawables that are located in the res/drawables folder.

From the documentation:

NOTE: Every corner must (initially) be provided a corner radius greater than 1, or else no corners are rounded. If you want specific corners to not be rounded, a work-around is to use android:radius to set a default corner radius greater than 1, but then override each and every corner with the values you really want, providing zero ("0dp") where you don't want rounded corners.

E.g. you have to set an android:radius="<bigger than 1dp>" to be able to do what you want:

<corners
android:radius="2dp"
android:bottomRightRadius="0dp"
android:topRightRadius="0dp"/>

This bug is filed here. This is a bug of android devices having API level less than 12. You've to put correct versions of your layouts in drawable-v12 folder which will be used for API level 12 or higher. And an erroneous version(corners switched/reversed) of the same layout will be put in the default drawable folder which will be used by the devices having API level less than 12.

For example: I had to design a button with rounded corner at bottom-right.

In 'drawable' folder - button.xml: I had to make bottom-left corner rounded.

<shape>
<corners android:bottomLeftRadius="15dp"/>
</shape>

In 'drawable-v12' folder - button.xml: Correct version of the layout was placed here to be used for API level 12 or higher.

<shape>
<corners android:bottomLeftRadius="15dp"/>
</shape>

for others there are a solution for any API level , you can place a item on top of each other example :

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >


<!-- my firt item with 4 corners radius(8dp)
-->
<item>
<shape>
<solid
android:angle="270.0"
android:color="#3D689A" />


<corners android:topLeftRadius="8dp" />
</shape>
</item>
<!-- my second item is on top right for a fake corner radius(0dp)
-->
<item
android:bottom="30dp"
android:left="50dp">
<shape>
<solid android:color="#5C83AF" />
</shape>
</item>
<!-- my third item is on bottom left for a fake corner radius(0dp)
-->
<item
android:right="50dp"
android:top="30dp">
<shape>
<solid android:color="#5C83AF" />
</shape>
</item>


</layer-list>

the result with light color to show you the three items :

the final result :

Best regards.

try this

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="@color/upkia"/>
<corners android:radius="10dp"
android:topRightRadius="0dp"
android:bottomRightRadius="0dp" />
</shape>

This works for me

  <?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="@color/colorPrimary" />
<corners
android:bottomLeftRadius="0dp"
android:radius="@dimen/dimen_5dp"
android:topLeftRadius="0dp" />
</shape>