Question

当我尝试旋转屏幕时，它不会删除数据，但是当我离开活动并返回时，计数器值会回到0。

我已经设置了保存数据的方法，但它仍然没有保存。这是为什么？

  package com.example.navjeevenmann.mytycoon;

  import android.content.Intent;
  import android.os.Bundle;
  import android.os.Handler;
 import android.support.v7.app.AppCompatActivity;
  import android.view.View;
   import android.widget.Button;
  import android.widget.TextView;


 public class MainActivity extends AppCompatActivity {
private Button myButton;
private int Counter = 0;
private Button myButton2;
private TextView myTextView;
Handler handler = new Handler();
private int add = 0;

@Override
protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (savedInstanceState != null) {
        Counter = savedInstanceState.getInt("Count");
        add = savedInstanceState.getInt("Add");
    }
    setContentView(R.layout.activity_main);
    myButton = (Button) findViewById(R.id.button);
    myButton2 = (Button) findViewById(R.id.button2);
    myTextView = (TextView) findViewById(R.id.textView);


    myButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Counter = ButtonCounter(Counter);
        }
    });
    myButton2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(getApplicationContext(), 
 SecondActivity.class);
            intent.putExtra("Count", Counter);
            startActivity(intent);
            finish();
        }

    });

    handler.postDelayed(new Runnable() {
        @Override
        public void run() {
            Counter = AutoCounter(Counter, add);
            Display(Counter, myTextView);
            handler.postDelayed(this, 100);
        }
    }, 10);


}

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    savedInstanceState.putInt("Count", Counter);
    savedInstanceState.putInt("Add", add);

    super.onSaveInstanceState(savedInstanceState);
}


public int ButtonCounter(int Counter) {
    Counter += 1;
    return Counter;
}

public int AutoCounter(int Counter, int add) {
    Counter += add;
    return Counter;
}

public void Display(int Counter, TextView myTextView) {
    String man = String.valueOf(Counter);
    myTextView.setText("$" + man);
}


}

Answer 1

我的代码就是这样......

@Override
protected void onSaveInstanceState(Bundle outState)
{
    super.onSaveInstanceState(outState);

    outState.putInt("Count", Counter);
}

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    if (savedInstanceState != null)
    {
        if (savedInstanceState.containsKey("Count"))
        {
            Counter = savedInstanceState.getInt("Count");
        }
    }
}

不同之处在于我没有创建最终的Bundle而且我在super.onSave之后保存它..这看起来很奇怪....

onsaveInstancestate不保存int值

1 个答案: