因此​​，对于这个我想需要2整数值在主要活动提供的2 EditTexts用户输入并添加在一起。然后，我希望Android应用程序切换到第二个活动，并在盒子的EditText显示有进入2盒的EditText从previous 2值的总和（主）活动。

我觉得我在正确的轨道上，但我不是很肯定如何获得在第二个活动的总和。我试着束和搞乱这样的，但是我还是不太明白。

的* *重新编辑，以反映一些建议。第二届活动仍然没有显示总...我想这是某种形式的转换错误。

***，我几乎可以肯定它是与第二Activity..the首先查找我的权利

**完美！这是一个转换错误。感谢所有的帮助：D

 进口android.os.Bundle;进口android.app.Activity;进口android.content.Intent;进口android.view.Menu;进口android.view.View;进口android.widget.EditText;公共类MainActivity扩展活动{    @覆盖    保护无效的onCreate（捆绑savedInstanceState）    {        super.onCreate（savedInstanceState）;        的setContentView（R.layout.activity_main）;    }    @覆盖    公共布尔onCreateOptionsMenu（菜单菜单）    {        //充气菜单;如果是present这增加了项目操作栏。        。getMenuInflater（）膨胀（R.menu.activity_main，菜单）;        返回true;    }    公共无效的OnClick（视图V）//安卓的onClick =onclick事件添加到activity_main.xml中这个按钮    {        意向意图=新意图（MainActivity.this，Summation.class）;    V1的EditText =（EditText上）findViewById（R.id.editText1）;    V2的EditText =（EditText上）findViewById（R.id.editText2）;    INT第一=的Integer.parseInt（v1.getText（）的toString（））;    INT秒=的Integer.parseInt（v2.getText（）的toString（））;    字符串总和=将String.valueOf（第一+第二）;    intent.putExtra（求和，总和）;    startActivity（意向）;    }} 

第二个活动类

 进口android.app.Activity;进口android.content.Intent;进口android.os.Bundle;进口android.widget.EditText;公共类求和扩展活动{    //第二项活动    @覆盖    保护无效的onCreate（捆绑savedInstanceState）    {        super.onCreate（savedInstanceState）;        的setContentView（R.layout.activity_2）;        字符串总和=（getIntent（）getExtras（）的getString（总和））;        的EditText ADDSUM =（EditText上）findViewById（R.id.editText1）;        addsum.setText（总和）;    }} 

解决方案

您不能直接从指定的EditText你的 INT 值。您需要分配像

 的EditText eText1 =（EditText上）findViewById（R.id.yourfirstedittext） 

和与你的第二个相同。然后得到的值

INT firstNum =的Integer.parseInt（eText1.getValue.toString（））

和当然与第二相同。然后，您可以添加这两个整数在一起，轻松地与通过他们intent.putExtra（苏木，总和）然后。让他们在你的第二个活动与 getIntent（）

 意图CI = getIntent（）;最终诠释总和= ci.getIntExtra（求和，yourDefaultIntValue） 

如果您传递作为 INT 你需要做这种方式并获得了字符串价值在 INT 。但是，如果你通过为字符串那么你的罚款

So for this I am trying to take 2 integer values the user inputs in the 2 EditTexts provided in the main activity and add them together. Then, I want the android application to switch to the 2nd Activity and in the EditText box there display the sum of the 2 values entered into the 2 EditText boxes from the previous(main) Activity.

I think I'm on the right track, but I'm not quite certain how to obtain the sum in the second activity. I've tried messing with bundles and such, but I still can't quite figure it out.

**Re-edited to reflect some suggestions. The 2nd activity still does not show the total...I'm thinking it's a conversion error of some sort.

***I'm almost positive it has something to do with the 2nd Activity..the first looks right to me

**PERFECT! It was a conversion error. Thanks all for the help :D

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;


public class MainActivity extends Activity 
{   

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

    @Override
    public boolean onCreateOptionsMenu(Menu menu) 
    {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    public void OnClick(View v) //android:onClick="OnClick"   added to activity_main.xml for this button
    {
        Intent intent = new Intent(MainActivity.this, Summation.class);
    EditText v1 = (EditText)findViewById(R.id.editText1);
    EditText v2 = (EditText)findViewById(R.id.editText2);   
    int first =  Integer.parseInt(v1.getText().toString());
    int second = Integer.parseInt(v2.getText().toString());
    String sum = String.valueOf(first + second);
    intent.putExtra("sum", sum);
    startActivity(intent);          
    }
}

Second Activity Class

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.EditText;

public class Summation extends Activity 
{
    //Second Activity 

    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {   
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_2);        
        String sum = (getIntent().getExtras().getString("sum"));
        EditText addsum = (EditText)findViewById(R.id.editText1);
        addsum.setText(sum);

    }   
}

You can't assign your int value straight from edittext. You need to assign the edit texts like

EditText eText1 = (EditText) findViewById(R.id.yourfirstedittext)

and the same with your second. Then get the values

int firstNum = Integer.parseInt(eText1.getValue.toString())

and of course the same with the second. You can then add these two ints together and simply pass them with intent.putExtra("sume, sum). Then get them in your second Activity with getIntent()

Intent ci = getIntent();
final int sum = ci.getIntExtra("sum", yourDefaultIntValue)

If you are passing as an int you will need to do it this way and get the String value of the int. But if you pass as a String then you are fine