问居中浮动窗口/活动？

EN

Style:
<style name="Theme.FloatingWindow.Popup.ClosableOnTouch" parent="Theme.AppCompat.Light.NoActionBar" >
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowCloseOnTouchOutside">true</item>
</style>

public void setupDisplay(){
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND,
            WindowManager.LayoutParams.FLAG_DIM_BEHIND);
    getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
    WindowManager.LayoutParams params = getWindow().getAttributes();
    params.alpha = 1.0f;    // lower than one makes it more transparent
    params.dimAmount = 0.75f;  // set it higher if you want to dim behind the window
    getWindow().setAttributes(params);
    Display display = getWindowManager().getDefaultDisplay();
    Point size = new Point();
    display.getSize(size);
    int width = size.x;
    int height = size.y;
    getWindow().setLayout((int) (width * .9), (int) (height * .7));
}