全屏沉浸模式ImmersiveMode

2019-11-10 17:54:43

字體：大中小

來源：轉載

供稿：網友

在寫播放器的時候，遇到了關于全屏模式的坑。翻閱了網上一些資料和google 官方的demo后，終于把坑填完了。

全屏主要的干擾就是頂部狀態欄stateBar和部分手機的虛擬按鍵NavigationBar。

這是google demo的源碼：

    /**     * Detects and toggles immersive mode (also known as "hidey bar" mode).     */    public void toggleHideyBar() {        // BEGIN_INCLUDE (get_current_ui_flags)        // The UI options currently enabled are rePResented by a bitfield.        // getSystemUiVisibility() gives us that bitfield.        int uiOptions = getActivity().getWindow().getDecorView().getSystemUiVisibility();        int newUiOptions = uiOptions;        // END_INCLUDE (get_current_ui_flags)        // BEGIN_INCLUDE (toggle_ui_flags)        boolean isImmersiveModeEnabled =                ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);        if (isImmersiveModeEnabled) {            Log.i(TAG, "Turning immersive mode mode off. ");        } else {            Log.i(TAG, "Turning immersive mode mode on.");        }        // Navigation bar hiding:  Backwards compatible to ICS.        if (Build.VERSION.SDK_INT >= 14) {            newUiOptions ^= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;        }        // Status bar hiding: Backwards compatible to Jellybean        if (Build.VERSION.SDK_INT >= 16) {            newUiOptions ^= View.SYSTEM_UI_FLAG_FULLSCREEN;        }        // Immersive mode: Backward compatible to KitKat.        // Note that this flag doesn't do anything by itself, it only augments the behavior        // of HIDE_NAVIGATION and FLAG_FULLSCREEN.  For the purposes of this sample        // all three flags are being toggled together.        // Note that there are two immersive mode UI flags, one of which is referred to as "sticky".        // Sticky immersive mode differs in that it makes the navigation and status bars        // semi-transparent, and the UI flag does not get cleared when the user interacts with        // the screen.        if (Build.VERSION.SDK_INT >= 18) {            newUiOptions ^= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;        }        getActivity().getWindow().getDecorView().setSystemUiVisibility(newUiOptions);        //END_INCLUDE (set_ui_flags)    }
這個demo比較簡單，不做詳細的解釋。就簡單的介紹下Flag等意思。
getActivity().getWindow().getDecorView() //獲取當前頁面的跟布局。View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;//控制NavigationBar的隱藏于顯示。View.SYSTEM_UI_FLAG_FULLSCREEN;//控制stateBar的隱藏與顯示。View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;這個標簽比較有趣。其實這個標簽有兩個：View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY 和 View.SYSTEM_UI_FLAG_IMMERSIVE。這兩個標簽都必須和View.SYSTEM_UI_FLAG_HIDE_NAVIGATION、View.SYSTEM_UI_FLAG_FULLSCREEN 一起使用。下面分為3中情況：
1、只使用View.SYSTEM_UI_FLAG_HIDE_NAVIGATION 和 View.SYSTEM_UI_FLAG_FULLSCREEN 。
這種情況下，在進入全屏模式后，用戶有任何操作，SYSTEM_UI_FLAG_HIDE_NAVIGATION和SYSTEM_UI_FLAG_FULLSCREEN 就會被清除。狀態欄和虛擬按鍵會一直可見。除非再次設置SYSTEM_UI_FLAG_HIDE_NAVIGATION和SYSTEM_UI_FLAG_FULLSCREEN。在狀態欄和虛擬按鍵顯示變化時會調用View.OnSystemUiVisibilityChangeListener。
2、SYSTEM_UI_FLAG_IMMERSIVE 配合View.SYSTEM_UI_FLAG_HIDE_NAVIGATION 和 View.SYSTEM_UI_FLAG_FULLSCREEN使用。
用戶操作不會清除SYSTEM_UI_FLAG_HIDE_NAVIGATION和SYSTEM_UI_FLAG_FULLSCREEN。會一直保持全屏模式。顯示切換時也會觸發View.OnSystemUiVisibilityChangeListener。還有一個區別就是 ，全屏模式時，從原本狀態欄或者虛擬按鍵的位置 響屏幕內部滑動，會清除SYSTEM_UI_FLAG_HIDE_NAVIGATION和SYSTEM_UI_FLAG_FULLSCREEN，保持可見狀態，并且也會觸發View.OnSystemUiVisibilityChangeListener監聽。3.SYSTEM_UI_FLAG_IMMERSIVE_STICKY配合View.SYSTEM_UI_FLAG_HIDE_NAVIGATION 和 View.SYSTEM_UI_FLAG_FULLSCREEN使用。
用戶操作不會清除SYSTEM_UI_FLAG_HIDE_NAVIGATION和SYSTEM_UI_FLAG_FULLSCREEN。會一直保持全屏模式。顯示切換時也會觸發View.OnSystemUiVisibilityChangeListener。，全屏模式時，，從原本狀態欄或者虛擬按鍵的位置 響屏幕內部滑動， 狀態欄 和 虛擬按鍵欄會暫時可見，一段時間后自動隱藏。與SYSTEM_UI_FLAG_IMMERSIVE 不同的是，因為是臨時的顯示，所以不會觸發View.OnSystemUiVisibilityChangeListener?？赡苷f的有點混亂，可以參考下下面的表格。
個人覺得使用toggleHideyBar()來控制有點不順手，所以拆分成了showBar()和hideBar()。
    public void showBar(){        int uiOptions = getWindow().getDecorView().getSystemUiVisibility();        int newUiOptions = uiOptions;        boolean isImmersiveModeEnabled =                ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);        if (isImmersiveModeEnabled) {            Log.i(TAG, "Turning immersive mode mode off. ");                        //先取 非 后再 與， 把對應位置的1 置成0，原本為0的還是0                        if (Build.VERSION.SDK_INT >= 14) {                newUiOptions &= ~View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;            }                       if (Build.VERSION.SDK_INT >= 16) {                newUiOptions &= ~View.SYSTEM_UI_FLAG_FULLSCREEN;            }                    if (Build.VERSION.SDK_INT >= 18) {                newUiOptions &= ~View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;            }            getWindow().getDecorView().setSystemUiVisibility(newUiOptions);        }    }    public void hideBar() {        // The UI options currently enabled are represented by a bitfield.        // getSystemUiVisibility() gives us that bitfield.        int uiOptions = getWindow().getDecorView().getSystemUiVisibility();        int newUiOptions = uiOptions;        boolean isImmersiveModeEnabled =                ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);        if (!isImmersiveModeEnabled) {            Log.i(TAG, "Turning immersive mode mode on. ");                  if (Build.VERSION.SDK_INT >= 14) {                newUiOptions |= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;            }                     if (Build.VERSION.SDK_INT >= 16) {                newUiOptions |= View.SYSTEM_UI_FLAG_FULLSCREEN;            }            if (Build.VERSION.SDK_INT >= 18) {                newUiOptions |= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;            }            getWindow().getDecorView().setSystemUiVisibility(newUiOptions);        }    }暫時就寫這么多吧。