java的ArrayList排序

紀錄一下，在android常用到
例如最新的文章的排序要在最高層～

ArrayList myData = new ArrayList();

升冪 ascending
Collections.sort(myData, new Comparator() {
@Override
public int compare(News n1, News n2) {
return n1.Id - n2.Id;
}
});


descending 降冪
Collections.sort(myData,
Collections.reverseOrder(new Comparator() {
@Override
public int compare(News n1, News n2) {
return n1.Id - n2.Id;
}
}));

在app中開啟外部app

筆記一下開外部app的寫法

private void startOthersApp(String packagename) {
Intent i = new Intent(Intent.ACTION_MAIN);
PackageManager manager = getPackageManager();
try {
i = manager.getLaunchIntentForPackage(packagename);

if (i == null)
throw new PackageManager.NameNotFoundException();
else {
i.addCategory(Intent.CATEGORY_LAUNCHER);
i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(i);
}
} catch (PackageManager.NameNotFoundException e) {
}
}