FullscreenControlsManager.java

package com.google.android.stardroid.activities.util;

import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.Activity;
import android.os.Handler;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

import com.google.android.stardroid.util.MiscUtil;

import java.util.ArrayList;
import java.util.List;

/**
 * Manages the showing and hiding of controls and system UI in full screen mode.
 *
 * Created by johntaylor on 2/21/16.
 */
public class FullscreenControlsManager {
  private static final String TAG = MiscUtil.getTag(FullscreenControlsManager.class);
  /**
   * 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 = 1000;

  /**
   * Some older devices needs a small delay between UI widget updates
   * and a change of the status and navigation bar.
   */
  private static final int UI_ANIMATION_DELAY = 300;

  private Activity mActivity;
  private View mContentView;
  private List<View> mViewsToHide;
  private boolean mVisible;

  public FullscreenControlsManager(
          Activity parentActivity, View contentView,
          List<View> viewsToHide, List<View> viewsToTriggerHide) {
    mActivity = parentActivity;
    mVisible = true;
    mViewsToHide = new ArrayList(viewsToHide);
    mContentView = contentView;

    // Upon interacting with UI controls, delay any scheduled hide()
    // operations to prevent the jarring behavior of controls going away
    // while interacting with the UI.
    for (View buttonView : viewsToTriggerHide) {
      buttonView.setOnTouchListener(mDelayHideTouchListener);
    }
  }

  public void toggleControls() {
    Log.d(TAG, "Toggling the UI");
    toggle();
  }

  /**
   * Quickly exposes the controls so that the user knows they're there.
   */
  public void flashTheControls() {

    // Trigger the initial hide() shortly after the activity has been
    // created, to briefly hint to the user that UI controls
    // are available.
    delayedHide(1000);
  }

  public void delayHideTheControls() {
    delayedHide(AUTO_HIDE_DELAY_MILLIS);
  }

  /**
   * 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.
   */
  private final View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() {
    @Override
    public boolean onTouch(View view, MotionEvent motionEvent) {
      if (AUTO_HIDE) {
        delayedHide(AUTO_HIDE_DELAY_MILLIS);
      }
      return false;
    }
  };

  private void toggle() {
    if (mVisible) {
      hide();
    } else {
      show();
    }
  }

  private void hide() {
    // Hide UI first
    ActionBar actionBar = mActivity.getActionBar();
    if (actionBar != null) {
      actionBar.hide();
    }
    for (View view : mViewsToHide) {
      view.setVisibility(View.GONE);
    }
    mVisible = false;

    // Schedule a runnable to remove the status and navigation bar after a delay
    mHideHandler.removeCallbacks(mShowPart2Runnable);
    mHideHandler.postDelayed(mHidePart2Runnable, UI_ANIMATION_DELAY);
  }

  private final Runnable mHidePart2Runnable = new Runnable() {
    @SuppressLint("InlinedApi")
    @Override
    public void run() {
      // Delayed removal of status and navigation bar

      // Note that some of these constants are new as of API 16 (Jelly Bean)
      // and API 19 (KitKat). It is safe to use them, as they are inlined
      // at compile-time and do nothing on earlier devices.
      mContentView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE
              | View.SYSTEM_UI_FLAG_FULLSCREEN
              | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
              | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
              | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
              | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
    }
  };

  @SuppressLint("InlinedApi")
  private void show() {
    // Show the system bar
    mContentView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
            | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION);
    mVisible = true;

    // Schedule a runnable to display UI elements after a delay
    mHideHandler.removeCallbacks(mHidePart2Runnable);
    mHideHandler.postDelayed(mShowPart2Runnable, UI_ANIMATION_DELAY);
  }

  private final Runnable mShowPart2Runnable = new Runnable() {
    @Override
    public void run() {
      // Delayed display of UI elements
      ActionBar actionBar = mActivity.getActionBar();
      if (actionBar != null) {
        actionBar.show();
      }
      for (View view : mViewsToHide) {
        view.setVisibility(View.VISIBLE);
      }
    }
  };

  private final Handler mHideHandler = new Handler();

  private final Runnable mHideRunnable = new Runnable() {
    @Override
    public void run() {
      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);
  }
}