将文本从一种积极性转移到另一项活动

Question

I have to activitys, "Main" and "Shop" and i got a variable in "Shop" that i would like to use in my "Main"-Activity, how can i do that? Thanks for help. I would like to have the intCountValue2 in my "Main" class. That is my whole Shop code:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_shop);

    btnBuyClickMultiplier = (Button) findViewById(R.id.ClickMultiplierButton);
    txtMultiplierCounter= (TextView) findViewById(R.id.ClickMultiplier);

    btnBuyClickMultiplier.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String CountValue2= txtMultiplierCounter.getText().toString();
            int intCountValue2 = Integer.parseInt(CountValue2);
            intCountValue2++;
            txtMultiplierCounter.setText(String.valueOf(intCountValue2));
        }
    });

    configureBackButton1();
}

private void configureBackButton1() {
    Button BackButton1 = (Button) findViewById(R.id.BackButton1);
    BackButton1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            finish();
        }
    });
}

Answer 1

The easisest way to do it but not the best is to declare your variable "shop" as public and static like the following:

public static String shop;

And then you can just call that variable in your Main activity as the following:

ShopActivity.shop;

Answer 2

Before starting Android Programming, you must have a good knowledge about Object Oriented Programming. However, to solve your problem you may try to use Getter and Setter method concept (In this particular case, only getter is needed). To do this in your particular case:

• At first, in your Shop class declare a private variable (obviously outside any methods, like- onCreate() or so) like this:

   private int count; 

• Then, create a public method in Shop class like this:

   public int getCount() { return this.count; } 

• Now, in your onCreate() method of Shop class, inside the setOnClickListener of btnBuyClickMultiplier , set the value of count to intCountValue2 like this:

   btnBuyClickMultiplier.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String CountValue2= txtMultiplierCounter.getText().toString(); int intCountValue2 = Integer.parseInt(CountValue2); intCountValue2++; txtMultiplierCounter.setText(String.valueOf(intCountValue2)); count = intCountValue2; } }); 

• Finally, you can access the value of intCountValue2 variable from the instance of Shop class created inside Main class like this:

   Shop s = new Shop(); int intCountvalue2 = s.getCount(); 

Hope you understand.