您好我正在尝试学习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。
我想要做的第一个编辑是添加一个复选框，用户可以检查在显示最终内容时会添加另一行文本。但是我不确定如何在代码中添加复选框（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，如果我没有清楚解释）
这里是2个活动的代码到目前为止，如果它有帮助，请基本与你的答案我没有编程一段时间和Ive大麦使用java之前所以我仍然得到了解决方案。
MainActivity：
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);
}
}
答案 0 :(得分：0)
你可以在附加内容中放入多个内容：
public class MainActivity extends Activity {
// ...
public void sendMessage(View view){
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.EditText);
String message = editText.getText().toString();
Bundle bundle = new Bundle();
bundle.putString(DisplayMessageActivity.KEY_BUNDLE_SOME_VALUE, message);
bundle.putString(DisplayMessageActivity.KEY_BUNDLE_SOME_OTHER_VALUE, someOtherValue);
intent.putExtras(bundle);
startActivity(intent);
}
// ...
}
在接收活动中：
public class DisplayMessageActivity extends Activity {
public static final String KEY_BUNDLE_SOME_VALUE = "some_value";
public static final String KEY_BUNDLE_SOME_OTHER_VALUE = "some_other_value";
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle bundle = getIntent().getExtras();
String string1 = "";
String string2 = "";
if (bundle != null) {
if (bundle.containsKey(KEY_BUNDLE_SOME_VALUE) {
string1 = bundle.getString(KEY_BUNDLE_SOME_VALUE);
}
if (bundle.containsKey(KEY_BUNDLE_SOME_OTHER_VALUE) {
string2 = bundle.getString(KEY_BUNDLE_SOME_OTHER_VALUE);
}
}
// ...
}
// ...
}
在捆绑密钥的接收活动中添加公共常量是个好主意。这将有助于防止你通过拼写错误犯错误:)如果你决定更新它们，他们就是1点。