Android: Ability to Auto-Hide the Title/Status Bars?

问题

I have a fullscreen drawing app that disables the title and status bars using the Android Theme.NoTitleBar.Fullscreen theme. One of the requests I am getting would be the ability to have these UI elements set to auto-hide, such that is the user touches near where they would be, they are shown. I can imagine ways to accomplish this using a custom Activity that emulates the title bar, but replacing the notification bar just isn't feasible.

So, just wondering if there is any way to auto-hide the OS standard title and status bars. I would imagine this is NO, as these elements look to be tied to the Activity in onCreate (or inflated from XML in onCreate), so once active, it wouldn't be possible to change their behavior.

回答1:

So, just wondering if there is any way to auto-hide the OS standard title and status bars.

None that I have seen.

Moreover, what your user is requesting can't be done generically -- what if there is a Button up "near where they would be"?

回答2:

Using android 3.1, one can set the visibility of the UI Status bar using

View.setSystemUiVisibility(View.STATUS_BAR_HIDDEN);

on touching where the status bar would be, the bar appears.

You can listen for this via the

View.setOnSystemUiVisibilityChangeListener 

method and then hide the bar again after some time

回答3:

I think the solution to your problem is right in the dummy Fullscreen project Android Studio has. Check it out:

    public class FullscreenActivity extends Activity {
        /**
         * Whether or not the system UI should be auto-hidden after
         * {@link #AUTO_HIDE_DELAY_MILLIS} milliseconds.
         */
        private static final boolean AUTO_HIDE = true;
        /**
         * If {@link #AUTO_HIDE} is set, the number of milliseconds to wait after
         * user interaction before hiding the system UI.
         */
        private static final int AUTO_HIDE_DELAY_MILLIS = 3000;

        /**
         * If set, will toggle the system UI visibility upon interaction. Otherwise,
         * will show the system UI visibility upon interaction.
         */
        private static final boolean TOGGLE_ON_CLICK = true;

        /**
         * The flags to pass to {@link SystemUiHider#getInstance}.
         */
        private static final int HIDER_FLAGS = SystemUiHider.FLAG_HIDE_NAVIGATION;

        /**
         * The instance of the {@link SystemUiHider} for this activity.
         */
        private SystemUiHider mSystemUiHider;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            setContentView(R.layout.activity_fullscreen);

            final View controlsView = findViewById(R.id.fullscreen_content_controls);
            final View contentView = findViewById(R.id.fullscreen_content);

            // Set up an instance of SystemUiHider to control the system UI for
            // this activity.
            mSystemUiHider = SystemUiHider.getInstance(this, contentView, HIDER_FLAGS);
            mSystemUiHider.setup();
            mSystemUiHider
                    .setOnVisibilityChangeListener(new SystemUiHider.OnVisibilityChangeListener() {
                        // Cached values.
                        int mControlsHeight;
                        int mShortAnimTime;

                        @Override
                        @TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
                        public void onVisibilityChange(boolean visible) {
                            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
                                // If the ViewPropertyAnimator API is available
                                // (Honeycomb MR2 and later), use it to animate the
                                // in-layout UI controls at the bottom of the
                                // screen.
                                if (mControlsHeight == 0) {
                                    mControlsHeight = controlsView.getHeight();
                                }
                                if (mShortAnimTime == 0) {
                                    mShortAnimTime = getResources().getInteger(
                                            android.R.integer.config_shortAnimTime);
                                }
                                controlsView.animate()
                                        .translationY(visible ? 0 : mControlsHeight)
                                        .setDuration(mShortAnimTime);
                            } else {
                                // If the ViewPropertyAnimator APIs aren't
                                // available, simply show or hide the in-layout UI
                                // controls.
                                controlsView.setVisibility(visible ? View.VISIBLE : View.GONE);
                            }

                            if (visible && AUTO_HIDE) {
                                // Schedule a hide().
                                delayedHide(AUTO_HIDE_DELAY_MILLIS);
                            }
                        }
                    });

            // Set up the user interaction to manually show or hide the system UI.
            contentView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    if (TOGGLE_ON_CLICK) {
                        mSystemUiHider.toggle();
                    } else {
                        mSystemUiHider.show();
                    }
                }
            });

            // Upon interacting with UI controls, delay any scheduled hide()
            // operations to prevent the jarring behavior of controls going away
            // while interacting with the UI.
            findViewById(R.id.dummy_button).setOnTouchListener(mDelayHideTouchListener);
        }

        @Override
        protected void onPostCreate(Bundle savedInstanceState) {
            super.onPostCreate(savedInstanceState);

            // Trigger the initial hide() shortly after the activity has been
            // created, to briefly hint to the user that UI controls
            // are available.
            delayedHide(100);
        }


        /**
         * Touch listener to use for in-layout UI controls to delay hiding the
         * system UI. This is to prevent the jarring behavior of controls going away
         * while interacting with activity UI.
         */
        View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() {
            @Override
            public boolean onTouch(View view, MotionEvent motionEvent) {
                if (AUTO_HIDE) {
                    delayedHide(AUTO_HIDE_DELAY_MILLIS);
                }
                return false;
            }
        };

        Handler mHideHandler = new Handler();
        Runnable mHideRunnable = new Runnable() {
            @Override
            public void run() {
                mSystemUiHider.hide();
            }
        };

        /**
         * Schedules a call to hide() in [delay] milliseconds, canceling any
         * previously scheduled calls.
         */
        private void delayedHide(int delayMillis) {
            mHideHandler.removeCallbacks(mHideRunnable);
            mHideHandler.postDelayed(mHideRunnable, delayMillis);
        }
}

来源：https://stackoverflow.com/questions/4904013/android-ability-to-auto-hide-the-title-status-bars