android - 具有透明状态栏的全屏 fragment (以编程方式)

Question

我有一个基于单个 Activity 和多个 fragment 的应用程序，有些 fragment 需要在进入 fragment 时显示为全屏，并在退出时从全屏退出。我目前正在使用标志在 Android Kitkat 中显示全屏，但我认为这不是最佳方式。我还阅读了 ImmersiveMode 但它在较低的 Android 版本中不起作用。目前我正在使用这些方法进行全屏进入和退出。

//This method not showing transparent status bar also navigation bar and not showing system icons either
public static void  setFullscreen(Activity activity) {
        if (Build.VERSION.SDK_INT > 10) {
            int flags = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN | View.SYSTEM_UI_FLAG_FULLSCREEN;
            boolean isImmersiveAvailable = android.os.Build.VERSION.SDK_INT >= 19;
            if (isImmersiveAvailable) {
                flags |= View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION |
                        View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
            }

            activity.getWindow().getDecorView().setSystemUiVisibility(flags);
        } else {
            activity.getWindow()
                    .setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
        }
    }

    public static void exitFullscreen(Activity activity) {
        if (Build.VERSION.SDK_INT > 10) {
            activity.getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
        } else {
            activity.getWindow()
                    .setFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN,
                            WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN);
        }
    }


 public static void ShowHideFullscreen(boolean isFullscreen,Context cntx){
        int newUiOptions = 0;
        if (isFullscreen){
            // BEGIN_INCLUDE (get_current_ui_flags)
            // The UI options currently enabled are represented by a bitfield.
            // getSystemUiVisibility() gives us that bitfield.
            int uiOptions = ((Activity)cntx).getWindow().getDecorView().getSystemUiVisibility();
            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.d(TAG, "Turning immersive mode mode off. ");
            } else {
                Log.d(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;
            }
            ((Activity)cntx).getWindow().getDecorView().setSystemUiVisibility(newUiOptions);

        }else {
            ((Activity)cntx).getWindow().clearFlags(newUiOptions);

        }
    }

这些是我们用来在带有隐藏操作栏的 fragment 中进入或退出全屏的方法。我们使用它们在 onCreate 上进入全屏并在 onPause 上退出，但有时它无法显示所需的结果。

我们也需要知道在较低的 API 上显示全屏 fragment 的最佳方式是什么(KITKAT)，以及在显示全屏时隐藏工具栏的最佳方式是什么，因为我们的代码 ((AppCompatActivity)Objects.requireNonNull( getActivity())).getSupportActionBar().hide();
有时会抛出 nullpointerexception。

我们的问题:

1. 在全屏 fragment 和透明导航栏上显示带有透明状态栏和绘图系统图标的全屏 fragment 。
2. 使用无需获取 NullpointerExepection 即可安全调用的方法隐藏和显示工具栏
3. 我们可以将 android Kitkat 定位为最低的 android 版本。

带有系统图标和透明导航栏的 fragment 全屏示例。

更新:我在我的 fragment onResume 上设置了 IMMERSIVE 模式，并通过这些方法将其重置回 onStop .

 private void hideSystemUI() {
        // Enables regular immersive mode.
        // For "lean back" mode, remove SYSTEM_UI_FLAG_IMMERSIVE.
        // Or for "sticky immersive," replace it with SYSTEM_UI_FLAG_IMMERSIVE_STICKY
        View decorView = getActivity().getWindow().getDecorView();
        decorView.setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                        // Set the content to appear under the system bars so that the
                        // content doesn't resize when the system bars hide and show.
                        | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        // Hide the nav bar and status bar
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN);
        ((AppCompatActivity) Objects.requireNonNull(getActivity())).getSupportActionBar().hide();

    }

    // Shows the system bars by removing all the flags
// except for the ones that make the content appear under the system bars.
    private void showSystemUI() {
        View decorView = getActivity().getWindow().getDecorView();
        decorView.setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
        ((AppCompatActivity) Objects.requireNonNull(getActivity())).getSupportActionBar().show();
    }

它以全屏显示我的 fragment 并隐藏状态栏(这不是我想要的)并且我的 fragment 属于 Navigation Drawer。当我从全屏 fragment 按下后退按钮时，它会在上一个 fragment 的工具栏上方显示我的状态栏。

Answer 1

我通过创建一个方法解决了这个问题，该方法在 onStop 清除所需的标志并在 onResume 添加标志

 @Override
    public void onResume() {
        super.onResume();
        App_Functions.transparentStatusBar(getActivity(),true,false);

    }

    @Override
    public void onStop() {
        super.onStop();
        App_Functions.transparentStatusBar(getActivity(),false,false);

    }

如果我想显示透明状态栏但导航栏应该相同，那么我在方法的第一个参数中使用 true 并清除该标志只需使用 false。与我使用 true 完全全屏和 false 清除全屏标志的方式相同

public static void transparentStatusBar(Activity activity, boolean isTransparent, boolean fullscreen) {
        if (isTransparent){
            activity.getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN | View.SYSTEM_UI_FLAG_LAYOUT_STABLE);
            ((AppCompatActivity) Objects.requireNonNull(activity)).getSupportActionBar().hide();
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                defaultStatusBarColor = activity.getWindow().getStatusBarColor();
                activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
                activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
                // FOR TRANSPARENT NAVIGATION BAR
                //activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
                activity.getWindow().setStatusBarColor(Color.TRANSPARENT);
                Log.d(TAG,"Setting Color Transparent "+Color.TRANSPARENT+ " Default Color "+defaultStatusBarColor);
            } else {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
                    Log.d(TAG,"Setting Color Trans "+Color.TRANSPARENT);
                    activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
                }
            }

        }else {
            if (fullscreen){
                View decorView = activity.getWindow().getDecorView();
                int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN;
                decorView.setSystemUiVisibility(uiOptions);

            }else {
                ((AppCompatActivity) Objects.requireNonNull(activity)).getSupportActionBar().show();
                activity.getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                    activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
                    activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
                    activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);
                    activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
                    activity.getWindow().setStatusBarColor(defaultStatusBarColor);

                }else {
                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
                        activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
                    }
                }

            }
                    }
    }

请随时推荐在所有平台上使用此方法的更好方法。