AppManager

AppManager 主要是管理 Activity 和 App 的管理类；里面主要方法有：添加 Activity 到堆栈，结束 Activity ，退出 App 等；下面是这个管理类的代码：

import android.app.Activity;
import android.app.ActivityManager;
import android.content.Context;

import java.util.Stack;

/**
 * author: wu
 * date: on 2018/10/26.
 * describe:AppManager类，管理Activity和App
 */

public class AppManager {
    private static Stack<Activity> activityStack;
    private static AppManager instace;

    private AppManager() {
    }

    /**
     * 单一实例
     */
    public static AppManager getAppManager() {
        if (instace == null) {
            instace = new AppManager();
        }
        return instace;
    }

    /**
     * 添加Activity到堆栈
     */
    public void addActivity(Activity activity) {
        if (activityStack == null) {
            activityStack = new Stack<>();
        }
        activityStack.add(activity);
    }

    /**
     * 获取当前Activity（堆栈最后一个加入的）
     */
    public Activity currentActivity() {
        Activity activity = activityStack.lastElement();
        return activity;
    }

    /**
     * 结束当前Activity（堆栈最后一个加入的）
     */
    public void finishActivity() {
        Activity activity = activityStack.lastElement();
        finishActivity(activity);
    }

    /**
     * 结束指定activity
     */
    public void finishActivity(Activity activity) {
        if (activity != null) {
            activityStack.remove(activity);
            activity.finish();
            activity = null;
        }
    }

    /**
     * 结束指定类名的Activity
     */
    public void finishActivity(Class<?> clas) {
        for (Activity activity : activityStack) {
            if (activity.getClass().equals(clas)) {
                finishActivity(activity);
            }
        }
    }

    /**
     * 结束所有Activity
     */
    public void finishAllActivity() {
        for (int i = 0; i < activityStack.size(); i++) {
            if (activityStack.get(i) != null) {
                activityStack.get(i).finish();
            }
        }
        activityStack.clear();
    }

    /**
     * 退出程序
     */
    public void exitApp(Context context) {
        try {
            finishAllActivity();
            ActivityManager manager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
            manager.restartPackage(context.getPackageName());
            System.exit(0);
        } catch (Exception e) {
        }
    }
}

下面是 AppManager 类的简单用法，一般是在封装的 BaseActivity 中使用：

import android.app.Activity;
import android.os.Bundle;

import com.example.qd.blackwu.manager.AppManager;

/**
 * author: wu
 * date: on 2018/10/27.
 * describe: 基类BaseActivity
 */

public class BaseActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // 添加Activity到堆栈
        AppManager.getAppManager().addActivity(this);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        // 结束Activity&从堆栈中移除
        AppManager.getAppManager().finishActivity(this);
    }
}