步驟：

• 在res下新建anim文件夾
• 在文件夾里新建pop_in.xml和pop_out.xml文件
• 在style文件中配置動(dòng)畫
• 在代碼中引用

代碼：
pop_in：

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration = "1000"
        android:fromYDelta="100%p"
        />
</set>

pop_out：

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration = "1000"
        android:toYDelta="50%p"
        />
</set>

style：

    <style name="pop_anim">
        <!--進(jìn)入動(dòng)畫-->
        <item name="android:windowEnterAnimation">@anim/pop_in</item>
        <!--退出動(dòng)畫-->
        <item name="android:windowExitAnimation">@anim/pop_out</item>
    </style>

activity中調(diào)用：

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button button = (Button) findViewById(R.id.btn);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                showPopWindow();
            }
        });
    }

    private void showPopWindow() {
        View inflate = LayoutInflater.from(this).inflate(R.layout.popwindow, null);

        PopupWindow popupWindow = new PopupWindow(inflate, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);

        // 設(shè)置popWindow彈出窗體可點(diǎn)擊，這句話必須添加，并且是true
        popupWindow.setFocusable(true);

        popupWindow.setAnimationStyle(R.style.pop_anim);

        popupWindow.showAtLocation(findViewById(R.id.start), Gravity.BOTTOM,0,0);
    }
}

demo下載