Java 为TextView赋值时出现空指针异常
我只想将值从一个活动传递到另一个活动,但无法从视图中找到Textview值。。我只是通过一个文本框将一条消息从主活动传递到此活动,我在这里看到了文本框的值,但无法将其分配给textView 这是我的密码Java 为TextView赋值时出现空指针异常,java,android,eclipse,android-layout,android-intent,Java,Android,Eclipse,Android Layout,Android Intent,我只想将值从一个活动传递到另一个活动,但无法从视图中找到Textview值。。我只是通过一个文本框将一条消息从主活动传递到此活动,我在这里看到了文本框的值,但无法将其分配给textView 这是我的密码 public class DisplayMessageActivity extends Activity { private TextView textView; @Override protected void onCreate(Bundle savedInstanceState) {
public class DisplayMessageActivity extends Activity {
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_message);
if (savedInstanceState == null) {
getFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
textView = (TextView) findViewById(R.id.displayText);
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
textView.setText(message);
}
XML
请帮帮我。此
文本视图不属于活动布局。将TextView
的初始化移动到placeholder fragment
的onCreateView
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_display_message, container, false);
TextView textView = (TextView) rootView.findViewById(R.id.displayText);
return rootView;
}
活跃
if (savedInstanceState == null) {
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
Bundle bundle = new Bundle();
bundle.putString("key", message);
PlaceholderFragment fragobj = new PlaceholderFragment();
fragobj.setArguments(bundle);
getFragmentManager().beginTransaction()
.add(R.id.container, fragobj).commit();
}
然后
您已从活动扩展,也可以使用此
TextView textView = (TextView) findViewById(R.id.displayText);
//in onCreate method
请发布堆栈跟踪。另外,您的XML是否位于布局文件夹中名为activity\u display\u message.XML
的文件中?感谢您的快速响应。。我不知道如何设置textview的值,但是如何从另一个片段获取意图值。。因为getIntent()给出了错误。。表示Intent=getIntent()的代码;字符串消息=intent.getStringExtra(MainActivity.EXTRA_消息)@asast1必须将值从活动传递到片段。
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_display_message, container, false);
TextView textView = (TextView) rootView.findViewById(R.id.displayText);
String strtext = getArguments().getString("key");
textView.setText(strtext);
return rootView;
}
View view = inflater.inflate(R.layout.fragment_display_message, container, false);
TextView textView = (TextView) view.findViewById(R.id.displayText);
return view; //in onCreate method
TextView textView = (TextView) findViewById(R.id.displayText);
//in onCreate method