嗨，我正在尝试学习 android 编程，我在这里使用了 android 教程：http: //developer.android.com/training/basics/firstapp/index.html但后来我要编辑它并添加我自己的位并通过使用 API 指南向他们学习。
我想做的第一个编辑是添加一个复选框，用户可以检查该复选框将在显示最后的内容时添加另一行文本。但是我不确定如何将复选框添加到代码中（在主活动中）并使其将数据发送到 DisplayMessageActivity 以告诉它在用户定义的另一行文本下添加另一行文本消息框，请帮忙（对不起，如果我没有解释清楚）
这是到目前为止 2 项活动的代码，如果有帮助的话，请对你的答案保持基本，我有一段时间没编程了，我之前用过 java，所以我还在做事情。
主要活动：
package com.hyper.benshelloworld;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.view.Menu;
import android.widget.CheckBox;
import android.widget.EditText;
/*
* private things can be directly accessed only within the class that defines them.
*•default (i.e., no access modifier) things can be accessed by any code in the same package as the defining class.
*•protected is like default, except subclasses outside of the defining package can also access the member.
*•public members are accessible to all code everywhere.
*/
public class MainActivity extends Activity {
public static final String EXTRA_MESSAGE = "com.hyper.benshelloworld.MESSAGE";
//defines the string EXTRA_MESSAGE
@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 sendMessage(View view){
Intent intent = new Intent(this, DisplayMessageActivity.class);
//calls on DisplayMessageActivity.class
EditText editText = (EditText) findViewById(R.id.EditText);
//makes the text box writable in.
String message = editText.getText().toString();
/*receives the typed message and makes it ready to be sent to the
* DisplayMessageActivity to be displayed*/
intent.putExtra(EXTRA_MESSAGE, message);
/*The most common use of intents is to start new activities (screens)within
* an application (line 41). The extras Bundle is a way of passing data between activities.
* Extras are entered as key value pairs so EXTRA_MESSAGE is a key is used to identify a
* particular value so it can be retrieved and used by another activity.
*/
startActivity(intent);
}
}
和 DisplayMessageActivity：
package com.hyper.benshelloworld;
/*
* private things can be directly accessed only within the class that defines them.
*•default (i.e., no access modifier) things can be accessed by any code in the same package as the defining class.
*•protected is like default, except subclasses outside of the defining package can also access the member.
*•public members are accessible to all code everywhere.
*/
import android.os.Build;
import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.support.v4.app.NavUtils;
import java.lang.String;
public class DisplayMessageActivity extends Activity {
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
//receives the intent sent in the MainActivity.class
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
//Uses the getStringExtra to receive the string message from MainActivity in the intent.
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
/*Sets up a text view to show the string "message" in and
*sets the size of the text
*/
if (message.equals("hello world")){
textView.setText("bit standard");
}
setContentView(textView);
//sets the activity to be showing the textView
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB){
/* If the android version is 3.0+,
* show the Up button in the action bar.
*/
getActionBar().setDisplayHomeAsUpEnabled(true);
}
}
@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_display_message, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// This ID represents the Home or Up button. In the case of this
// activity, the Up button is shown. Use NavUtils to allow users
// to navigate up one level in the application structure. For
// more details, see the Navigation pattern on Android Design:
//
// http://developer.android.com/design/patterns/navigation.html#up-vs-back
//
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
}