Android NoteX Q9: PopupWindow setOutsideTouchable 失效

设置为true后点击外部还是会被dismiss掉，这是为什么？

/**
 * 
Controls whether the pop-up will be informed of touch events outside
 * of its window.  This only makes sense for pop-ups that are touchable
 * but not focusable, which means touches outside of the window will
 * be delivered to the window behind.  The default is false.
 *
 * 
If the popup is showing, calling this method will take effect only
 * the next time the popup is shown or through a manual call to one of
 * the {@link #update()} methods.
 *
 * @param touchable true if the popup should receive outside
 * touch events, false otherwise
 *
 * @see #isOutsideTouchable()
 * @see #isShowing()
 * @see #update()
 */
public void setOutsideTouchable(boolean touchable) {
mOutsideTouchable = touchable;
}

从官方api的解释来看，当focusable=false时，设置setOutsideTouchable才有意义。那么设置了focusable=true时，就没有意义，因为focusable=true会拿走焦点事件，outside拿不到焦点，则的outside的touch就无用处了。

那如何实现既设置focusable=true，也要外部(outside)点击不被dismiss呢？

var isForceDismiss = false
override fun dismiss() {
if (isForceDismiss) {
super.dismiss()
isForceDismiss = true
    }
}

改写popupwindow的dismiss方法，做个逻辑判断即可。