在我的主要应用程序的活动,我下载了一些用户数据在 ONSTART()
。当我打开设置和我打了返回
按钮,我完成了设置活动
,我返回到主活动。问题是,正在重新下载的数据。
In my main Activity of the app, I download some user data at the onStart()
. When I open the Settings and I hit the Back
button, I finish the Settings Activity
and I return to the main Activity. The problem is that the data is being re-downloaded.
那么,怎样才能避免重新下载数据的?
So, how can avoid the re-downloading of data?
我有,虽然约 startActivityForResult
,但我不知道如何使用它,我不明白它是如何工作的。
I've though about startActivityForResult
but I don't know how to use it and I do not understand how it works.
感谢你在前进!
在这样的主活动类中定义一个静态变量:
Define a static variable in your main activity class like this:
public static bool download = true;
当您从设置返回的值更改为false,如:
When you are returning from settings change its value to false like:
MainActivity.download = false;
和把你的下载方法的if语句像这里面的:
And put your download method inside an if statement like this:
if (download) {
yourdownloadcode();
}