获取意图类加载器.我想在secondActivity中将textView中的textView设置为firstActivity的名称(实际上我需要类加载器的名称) [英] Get intent Class loader . I want to set text a textView in secondActivity to name of firstActivity (Actually I need class loader name)

问题描述

在从一种活动转到另一种活动的意图中，如何获得类加载器的名称? 我需要类加载器的名称. 如果我的意图不明确，请查看以下代码.

In going from an activity to another one by an intent, How can I get class loader name ? I need name of class loader. If my intention wasn't clear, Please look at this codes.

我为此问题创建了一个测试应用.它具有三个活动. ActivityA，ActivityB和ActivityC.我在ActivityA和ActivityB中都有一个启动activityC的按钮.

I created a test app for this Question. It has three activity. ActivityA , ActivityB and ActivityC. I have a button in ActivityA and ActivityB that start activityC.

ActivityA:

ActivityA:

 public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_a);

        Button btnGoFromActivityAToActivityC = (Button) findViewById(R.id.btnGoFromActivityAToActivityC);

        btnGoFromActivityAToActivityC.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(ActivityA.this, ActivityC.class);
                startActivity(intent);

            }
        });
    }

活动B:

public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_b);

        Button btnGoFromActivityBToActivityC = (Button) findViewById(R.id.btnGoFromActivityBToActivityC);

        btnGoFromActivityBToActivityC.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(ActivityB.this, ActivityC.class);
                startActivity(intent);

            }
        });
    }

ActivityC:

ActivityC:

 public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_c);

        TextView textViewNameOfFirstActivity = (TextView) findViewById(R.id.textViewNameOfFirstActivity);

   if (/*  if we came from ActivityA  */)
   {
       textViewNameOfFirstActivity.setText("You came from ActivityA");
   }

   else if (/*  if we came from ActivityB  */)
   {
       textViewNameOfFirstActivity.setText("You came from ActivityB");
   }
    }

看看ActivityC ...

Look at ActivityC...

我该怎么做?

推荐答案

ClassLoader不会告诉您Activity加载了什么内容.它用于加载类.

The ClassLoader isn't going to tell you what loaded your Activity; it's for loading Classes.

一种更好的方法是将某种信息发送到Activity C，告诉它谁打开了它.例如

A better approach would be to send some kind of info to Activity C that tells it who opened it. e.g.

活动A:

Intent intent = new Intent(ActivityA.this, ActivityC.class);
intent.putExtra("from", "Activity A");
startActivity(intent);

然后在Activity C的onCreate(Bundle)方法中，您将获得该值:

And then in your onCreate(Bundle) method of Activity C you would get that value:

@Override
public void onCreate(Bundle savedInstance){
    ....

    String fromActivity = getIntent().getStringExtra("from");

    textViewNameOfFirstActivity.setText(fromActivity);
}

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