我正在创建一个Android应用，我希望多个人可以访问相同的号码，并能够通过两个按钮更改该号码

Question

I am creating an app where people report whether or not they have the flu that week. I already have the code that allows me to be able to add to the number of people who do have the flu and the number of people who don't have the flu by pressing buttons. It then creates a percentage of people who have the flu based on that data. But whenever I close out of the app, all of the data goes away. The same data also won't be able to be accessed by the other people with the app. Here is the code for the app.

public void fluButton()
{
    Button hasFluButton = (Button)findViewById(R.id.fluButton);

    hasFluButton.setOnClickListener(
            new View.OnClickListener()
            {
                @Override
                public void onClick(View v)
                {
                    TextView t1 = (TextView)findViewById(R.id.influenzaPercent);
                    NumberFormat defaultFormat = NumberFormat.getPercentInstance();
                    defaultFormat.setMinimumFractionDigits(2);

                    numPeopleWFlu += 1;

                    percentFlu = ((double)numPeopleWFlu) / (numPeopleWOFlu + numPeopleWFlu);
                    String percent = defaultFormat.format(percentFlu);
                    t1.setText(percent + " of people have had the flu this week.");
                }
            }
    );
}

public void noFluButton()
{
    Button hasNoFluButton = (Button)findViewById(R.id.noFluButton);

    hasNoFluButton.setOnClickListener(
            new View.OnClickListener()
            {
                @Override
                public void onClick(View v)
                {
                    TextView t1 = (TextView)findViewById(R.id.influenzaPercent);
                    NumberFormat defaultFormat = NumberFormat.getPercentInstance();
                    defaultFormat.setMinimumFractionDigits(2);

                    numPeopleWOFlu += 1;

                    percentFlu = ((double)numPeopleWFlu) / (numPeopleWOFlu + numPeopleWFlu);
                    String percent = defaultFormat.format(percentFlu);
                    t1.setText(percent + " of people have had the flu in missouri this year.");
                }
            }
    );
}`.

Answer 1

This answer will only provide you with a very vague solution as your question is broad.

Here's what you need to do, you need to rent a server and put all the data to that server.

Why do you need a server? Because you want lots of people to access the data as the same time. If you save the data to your app's SharedPreferences or something local, other people won't be able to get it.

So now you have a server, in your app, you retrieve the data from the server at the start of your app. There are lots of external libraries out there that can help you fetch something from the internet.

After you retrieved the data, you display it in some views and BOOM! You did the first part. The second part is to save the data to the server. When the user taps on a button or something, you save the data.

Sounds easy, huh?