1、判断当前应用是否在前台

private fun isForeground(context: Context): Boolean {

val am = context.getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager

val tasks = am.getRunningTasks(1)

if (tasks != null && !tasks.isEmpty()) {

val topActivity = tasks[0].topActivity

if (topActivity.packageName == context.packageName) {

return true

}

}

return false

}

2、把当前应用切换到前台

private fun moveTaskToFront() {

val mAm = context.getSystemService(ACTIVITY_SERVICE) as ActivityManager

//获得当前运行的task

val taskList = mAm.getRunningTasks(100)

for (rti in taskList) {

//找到当前应用的task，并启动task的栈顶activity，达到程序切换到前台

if (rti.topActivity.packageName == context.packageName) {

mAm.moveTaskToFront(rti.id, 0)

return

}

}

}

3、添加权限