如何对字符串数据使用 putExtra() 和 getExtra() [英] How to use putExtra() and getExtra() for string data

问题描述

谁能告诉我如何使用 getExtra() 和 putExtra() 来实现意图?实际上我有一个字符串变量，比如str，它存储一些字符串数据.现在，我想将此数据从一个活动发送到另一个活动.

Can someone please tell me how exactly to use getExtra() and putExtra() for intents? Actually I have a string variable, say str, which stores some string data. Now, I want to send this data from one activity to another activity.

  Intent i = new Intent(FirstScreen.this, SecondScreen.class);   
  String keyIdentifer  = null;
  i.putExtra(strName, keyIdentifer );

然后在 SecondScreen.java

and then in the SecondScreen.java

 public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.table);
        TextView userName = (TextView)findViewById(R.id.userName);
        Bundle bundle = getIntent().getExtras();

        if(bundle.getString("strName")!= null)
        {
            //TODO here get the string stored in the string variable and do 
            // setText() on userName 
        }

    }

我知道这是一个非常基本的问题，但不幸的是我被困在这里.请帮忙.

I know it is very basic question but unfortunately I am stuck here. Please help.

谢谢，

这里我试图从一个屏幕传递到另一个屏幕的字符串是动态的.那就是我有一个 editText，无论用户键入什么，我都可以在其中获取字符串.然后在 myEditText.getText().toString() 的帮助下.我将输入的值作为字符串获取，然后我必须传递这些数据.

Here the string which I am trying to pass from one screen to the other is dynamic. That is I have an editText where I am getting string whatever user types. Then with the help of myEditText.getText().toString() . I am getting the entered value as a string then I have to pass this data.

推荐答案

用这个来放置"文件...

Use this to "put" the file...

Intent i = new Intent(FirstScreen.this, SecondScreen.class);   
String strName = null;
i.putExtra("STRING_I_NEED", strName);

然后，要检索该值，请尝试以下操作:

Then, to retrieve the value try something like:

String newString;
if (savedInstanceState == null) {
    Bundle extras = getIntent().getExtras();
    if(extras == null) {
        newString= null;
    } else {
        newString= extras.getString("STRING_I_NEED");
    }
} else {
    newString= (String) savedInstanceState.getSerializable("STRING_I_NEED");
}

这篇关于如何对字符串数据使用 putExtra() 和 getExtra()的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！