在Android项目中手动管理你的Activity

我们通常会使用系统自带的ActivityManager，但是在有些情况下使用起来不是太简洁。所以会自己来维护一个栈来管理这些activtiy

代码如下：

import java.util.Stack;

import android.app.Activity;
import android.util.Log;

public class ScreenManager
{
    private static final String TAG = "ScreenManager";
    private static Stack<Activity> activityStack;

    private static ScreenManager instance;

    /**
     * <单例方法>
     * <功能详细描述>
     * @return 该对象的实例
     * @see [类、类#方法、类#成员]
     */
    public static ScreenManager getScreenManager1()
    {
        if (instance == null)
        {
            instance = new ScreenManager();
        }
        return instance;
    }

    /**
     * <获取当前栈顶Activity>
     * <功能详细描述>
     * @return
     * @see [类、类#方法、类#成员]
     */
    public Activity currentActivity()
    {
        if (activityStack == null || activityStack.size() == 0)
        {
            return null;
        }
        Activity activity = activityStack.lastElement();

        Log.e(TAG, "get current activity:" + activity.getClass().getSimpleName());
        return activity;
    }

    /**
     * <将Activity入栈>
     * <功能详细描述>
     * @param activity
     * @see [类、类#方法、类#成员]
     */
    public void pushActivity(Activity activity)
    {
        if (activityStack == null)
        {
            activityStack = new Stack<Activity>();
        }
        Log.e(TAG, "push stack activity:" + activity.getClass().getSimpleName());
        activityStack.add(activity);
    }

    /**
     * <退出栈顶Activity>
     * <功能详细描述>
     * @param activity
     * @see [类、类#方法、类#成员]
     */
    public void popActivity(Activity activity)
    {
        if (activity != null)
        {
            activity.finish();
            Log.e(TAG, "remove current activity:" + activity.getClass().getSimpleName());
            activityStack.remove(activity);
            activity = null;
        }
    }

    /**
     * <退出栈中所有Activity,当前的activity除外>
     * <功能详细描述>
     * @param cls
     * @see [类、类#方法、类#成员]
     */
    public void popAllActivityExceptMain(Class cls)
    {
        while(true)
        {
            Activity activity = currentActivity();
            if (activity == null)
            {
                break;
            }
            if (activity.getClass().equals(cls))
            {
                break;
            }

            popActivity(activity);
        }
    }
}

具体使用：

 @Override
    protected void onCreate(Bundle savedInstanceState)
    {

        super.onCreate(savedInstanceState);

        ActivityManager am =  (ActivityManager)getSystemService("");
        am.
        ScreenManager.getScreenManager().pushActivity(this);
    }

    @Override
    protected void onDestroy()
    {
        super.onDestroy();
        ScreenManager.getScreenManager().popActivity(this);
    }


    /**
     * <退出系统>
     * <绑定退出按钮>
     * @param v
     * @see [类、类#方法、类#成员]
     */
    public void exitSystem(View v)
    {
        ScreenManager.getScreenManager().popAllActivityExceptMain(getClass());

        finish();
    }