Android studio使用android:style/Theme.Dialog报错:You need to use a Theme.AppCompat theme (or descendant)

查找缘由是在activity java代码部分继承了compatactivity

public class DialogActivity extends AppCompatActivity

可是在AndroidManifest.xml里面肯定义成Dialog,

<activity android:name=".DialogActivity"
    android:theme="@android:style/Theme.Dialog">
</activity>

解决方法是修改activity java代码,继承Activity便可:

public class DialogActivity extends Activity