Complete example of Activity management tool class developed by Android

This article illustrates the Activity management tool class developed by Android. Share it for your reference, as follows:

This tool class is a little management of Activity, which is very suitable

package com.maobang.imsdk.util;
import java.util.Stack;
import android.app.Activity;
import android.app.ActivityManager;
import android.content.Context;
import android.graphics.drawable.Drawable;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.widget.ImageView;
import android.widget.ListView;
/**
 * Activity Management class 
 * Created by Administrator on 2016/11/24.
 */
public class ActivityPageManager {
  private static Stack<Activity> activityStack;
  private static ActivityPageManager instance;
  /**
   * constructor
   */
  private ActivityPageManager() {
  }
  /**
   * get the AppManager instance, the AppManager is singleton.
   */
  public static ActivityPageManager getInstance() {
    if (instance == null) {
      instance = new ActivityPageManager();
    }
    return instance;
  }
  /**
   * add Activity to Stack
   */
  public void addActivity(Activity activity) {
    if (activityStack == null) {
      activityStack = new Stack<Activity>();
    }
    activityStack.add(activity);
  }
  /**
   * remove Activity from Stack
   */
  public void removeActivity(Activity activity) {
    if (activityStack == null) {
      activityStack = new Stack<Activity>();
    }
    activityStack.remove(activity);
  }
  /**
   * get current activity from Stack
   */
  public Activity currentActivity() {
    Activity activity = activityStack.lastElement();
    return activity;
  }
  /**
   * finish current activity from Stack
   */
  public void finishActivity() {
    Activity activity = activityStack.lastElement();
    finishActivity(activity);
  }
  /**
   * finish the Activity
   */
  public void finishActivity(Activity activity) {
    if (activity != null) {
      activityStack.remove(activity);
      activity.finish();
      activity = null;
    }
  }
  /**
   * finish the Activity
   */
  public void finishActivity(Class<?> cls) {
    for (Activity activity : activityStack) {
      if (activity.getClass().equals(cls)) {
        finishActivity(activity);
      }
    }
  }
  /**
   * finish all Activity
   */
  public void finishAllActivity() {
    if(activityStack!=null&&activityStack.size()>0)
    {
      for (int i = 0, size = activityStack.size(); i < size; i++) {
        if (null != activityStack.get(i)) {
          activityStack.get(i).finish();
        }
      }
      activityStack.clear();
    }
  }
  /**
   * release all resourse for view
   * @param view
   */
  public static void unbindReferences(View view) {
    try {
      if (view != null) {
        view.destroyDrawingCache();
        unbindViewReferences(view);
        if (view instanceof ViewGroup){
          unbindViewGroupReferences((ViewGroup) view);
        }
      }
    } catch (Throwable e) {
      // whatever exception is thrown just ignore it because a crash is
      // always worse than this method not doing what it's supposed to do
    }
  }
  private static void unbindViewGroupReferences(ViewGroup viewGroup) {
    int nrOfChildren = viewGroup.getChildCount();
    for (int i = 0; i < nrOfChildren; i++) {
      View view = viewGroup.getChildAt(i);
      unbindViewReferences(view);
      if (view instanceof ViewGroup)
        unbindViewGroupReferences((ViewGroup) view);
    }
    try {
      viewGroup.removeAllViews();
    } catch (Throwable mayHappen) {
      // AdapterViews, ListViews and potentially other ViewGroups don't
      // support the removeAllViews operation
    }
  }
  @SuppressWarnings("deprecation")
  private static void unbindViewReferences(View view) {
    // set all listeners to null (not every view and not every API level
    // supports the methods)
    try {
      view.setOnClickListener(null);
      view.setOnCreateContextMenuListener(null);
      view.setOnFocusChangeListener(null);
      view.setOnKeyListener(null);
      view.setOnLongClickListener(null);
      view.setOnClickListener(null);
    } catch (Throwable mayHappen) {
    }
    // set background to null
    Drawable d = view.getBackground();
    if (d != null){
      d.setCallback(null);
    }
    if (view instanceof ImageView) {
      ImageView imageView = (ImageView) view;
      d = imageView.getDrawable();
      if (d != null){
        d.setCallback(null);
      }
      imageView.setImageDrawable(null);
      imageView.setBackgroundDrawable(null);
    }
    // destroy WebView
    if (view instanceof WebView) {
      WebView webview = (WebView) view;
      webview.stopLoading();
      webview.clearFormData();
      webview.clearDisappearingChildren();
      webview.setWebChromeClient(null);
      webview.setWebViewClient(null);
      webview.destroyDrawingCache();
      webview.destroy();
      webview = null;
    }
    if (view instanceof ListView) {
      ListView listView = (ListView) view;
      try {
        listView.removeAllViewsInLayout();
      } catch (Throwable mayHappen) {
      }
      ((ListView) view).destroyDrawingCache();
    }
  }
  /**
   * exit System
   * @param context
   */
  public void exit(Context context) {
    exit(context, true);
  }
  /**
   * exit System
   * @param context
   * @param isClearCache
   */
  @SuppressWarnings("deprecation")
  public void exit(Context context, boolean isClearCache) {
    try {
      finishAllActivity();
      if(context != null){
        ActivityManager activityMgr = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        activityMgr.restartPackage(context.getPackageName());
      }
//      if(isClearCache){
//        LruCacheManager.getInstance().evictAll();
//        CacheManager.clearAll();
//      }
      System.exit(0);
      android.os.Process.killProcess(android.os.Process.myPid());
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

For more readers interested in Android related content, please check the topics of this site: "Summary of activity Operation Skills of Android Programming", "Introduction and Advanced Tutorial of Android Development", "Summary of View Skills of Android View", "Summary of Android File Operation Skills", "Summary of Android Resource Operation Skills" and "Summary of Android Control Usage"

I hope this article is helpful to everyone's Android programming.