android 清空之前task中的activity

开发过程有个场景：关闭之前所有activity,跳转到登录页

以前是activity都放到一个list里面，退出应用的时候遍历列表，逐个finish

换种实现方式

跳转登录页的intent添加两个flag 

Intent.FLAG_ACTIVITY_CLEAR_TASK

Intent.FLAG_ACTIVITY_NEW_TASK

Intent intent = new Intent(this, TestCActivity.class);
		intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
		intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
		startActivity(intent);

当然如果登录页的launchMode为singleTask的话，就不需要

Intent.FLAG_ACTIVITY_NEW_TASK

(要么在manifest文件中声明，要么在intent中添加flag,二者择一即可)

看下google文档

* If set in an Intent passed to {@link Context#startActivity Context.startActivity()},
     * this flag will cause any existing task that would be associated with the
     * activity to be cleared before the activity is started.  That is, the activity
     * becomes the new root of an otherwise empty task, and any old activities
     * are finished.  This can only be used in conjunction with {@link #FLAG_ACTIVITY_NEW_TASK}.

cet-4的基本能看懂吧~

备注apilevel要大于11