android 当文件夹路径从n层按back键退回到n-19层的时候，file manager自动退出

当文件夹路径从n层按back键退回到n-19层的时候，file manager自动退出，比如在63层按back 键退回到44层的时候，file manager自动退出。



1.FileManager默认设计, FileManager种只记录最多20条操作路径的记录, 如果超出就会把最早加入的记录删除. 贵司可以参考alps/mediatek/packages/apps/FileManager/src/com/mediatek/filemanager/FileInfoManager.java中这部分的代码．

/** Max history size */

private static final int MAX_LIST_SIZE = 20;

private final List<NavigationRecord> mNavigationList = new LinkedList<NavigationRecord>();

/**

* This method gets the previous navigation directory path

*

* @return the previous navigation path

*/

protected NavigationRecord getPrevNavigation() {

while (!mNavigationList.isEmpty()) {

NavigationRecord navRecord = mNavigationList.get(mNavigationList.size() - 1);

removeFromNavigationList();

String path = navRecord.getRecordPath();

if (!TextUtils.isEmpty(path)) {

if (new File(path).exists() || MountPointManager.getInstance().isRootPath(path)) {

return navRecord;

}

}

}

return null;

}

/**

* This method adds a navigationRecord to the navigation history

*

* @param navigationRecord the Record

*/

protected void addToNavigationList(NavigationRecord navigationRecord) {

if (mNavigationList.size() <= MAX_LIST_SIZE) {

mNavigationList.add(navigationRecord);

} else {

mNavigationList.remove(0);

mNavigationList.add(navigationRecord);

}

}

/**

* This method removes a directory path from the navigation history

*/

protected void removeFromNavigationList() {

if (!mNavigationList.isEmpty()) {

mNavigationList.remove(mNavigationList.size() - 1);

}

}





2.对于20条操作路径的history record, 贵司可以修改，只需要把FileInfo.Manager.java中的MAX_LIST_SIZE设为需要的最大路径记录数。这样修改带来的影响是，file manager APK可能会用到更多的内存，因为List<NavigationRecord> mNavigationList需要记录更多的路径数。

alps/mediatek/packages/apps/FileManager/src/com/mediatek/filemanager/FileInfoManager.java中这部分的代码．

/** Max history size */

private static final int MAX_LIST_SIZE = xxx;