Android 错误：android.widget.TextView.<init>
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【中文标题】Android 错误：android.widget.TextView.<init>【英文标题】：Android Error: android.widget.TextView.<init> 【发布时间】：2013-05-01 06:36:30 【问题描述】：我想在 ma Galaxy S2 中运行该应用程序，但我发现了这个错误。我发布了logcat。请告诉我有什么问题？以及如何解决？谢谢
05-07 11:23:38.820: D/androidRuntime(8900): Shutting down VM
05-07 11:23:38.820: W/dalvikvm(8900): threadid=1: thread exiting with uncaught exception (group=0x40c3f1f8)
05-07 11:23:38.820: E/AndroidRuntime(8900): FATAL EXCEPTION: main
05-07 11:23:38.820: E/AndroidRuntime(8900): java.lang.RuntimeException: Unable to instantiate activity ComponentInfocom.example.aaaaa/com.example.aaaaa.MainActivity: java.lang.NullPointerException
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1892)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1993)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread.access$600(ActivityThread.java:127)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1159)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.os.Handler.dispatchMessage(Handler.java:99)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.os.Looper.loop(Looper.java:137)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread.main(ActivityThread.java:4507)
05-07 11:23:38.820: E/AndroidRuntime(8900): at java.lang.reflect.Method.invokeNative(Native Method)
05-07 11:23:38.820: E/AndroidRuntime(8900): at java.lang.reflect.Method.invoke(Method.java:511)
05-07 11:23:38.820: E/AndroidRuntime(8900): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
05-07 11:23:38.820: E/AndroidRuntime(8900): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
05-07 11:23:38.820: E/AndroidRuntime(8900): at dalvik.system.NativeStart.main(Native Method)
05-07 11:23:38.820: E/AndroidRuntime(8900): Caused by: java.lang.NullPointerException
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.content.ContextWrapper.getResources(ContextWrapper.java:81)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.view.View.<init>(View.java:2721)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.view.View.<init>(View.java:2769)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.widget.TextView.<init>(TextView.java:573)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.widget.TextView.<init>(TextView.java:566)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.widget.TextView.<init>(TextView.java:561)
05-07 11:23:38.820: E/AndroidRuntime(8900): at com.example.aaaaa.MainActivity.<init>(MainActivity.java:28)
05-07 11:23:38.820: E/AndroidRuntime(8900): at java.lang.Class.newInstanceImpl(Native Method)
05-07 11:23:38.820: E/AndroidRuntime(8900): at java.lang.Class.newInstance(Class.java:1319)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.Instrumentation.newActivity(Instrumentation.java:1026)
05-07 11:23:38.820: E/AndroidRuntime(8900): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1883)
05-07 11:23:38.820: E/AndroidRuntime(8900): ... 11 more
这是 MainActivity.java 我认为错误在 TextView view = new TextView(this); 中，因为我在 MainActivity 中没有 TextView，但我想从另一个类 (setting.java) 中的 textview 中提取数据
import java.util.ArrayList;
import java.util.List;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.ItemizedOverlay;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.OverlayItem;
public class MainActivity extends MapActivity
String num;
TextView view = new TextView(this);
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Bundle extra = getIntent().getExtras();
num = extra.getString("label");
final TextView view = new TextView(this);
Uri uriSMSURI = Uri.parse("content://sms/inbox");
Cursor cur = getContentResolver().query(uriSMSURI, null, null, null,null);
String sms = "";
while (cur.moveToNext())
String spn ="+21629188153";
String phNum =cur.getString(2);
if (spn.equals(phNum))
sms +=cur.getString(12);
String a =sms.substring(0,10);
String b =sms.substring(11,21);
MapView maMap;
MapController monControler;
maMap = (MapView)findViewById(R.id.myGmap);
maMap.setBuiltInZoomControls(true);
GeoPoint point = new GeoPoint (microdegrees(Double.parseDouble(a)),microdegrees(Double.parseDouble(b)));
MonOverlay object = new MonOverlay(getResources().getDrawable(R.drawable.marker_voisinage_rouge));
object.addPoint(point);
maMap.getOverlays().add(object);
maMap.setSatellite(true);
monControler = maMap.getController();
monControler.setZoom(12);
monControler.setCenter(point);
Button monBouton = (Button)findViewById(R.id.envoie_sms);
monBouton.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
View monBoutton = null;
// TODO Auto-generated method stub
Intent monIntent = new Intent(MainActivity.this,SendSms.class);
startActivity(monIntent);
);
Button mnBouton = (Button)findViewById(R.id.setting);
mnBouton.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
View monBoutton = null;
// TODO Auto-generated method stub
setContentView(R.layout.setting);
);
Button myBouton = (Button)findViewById(R.id.aff);
myBouton.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
View monBoutton = null;
// TODO Auto-generated method stub
view.setText(num);
setContentView(view);
);
private int microdegrees (double value)
return (int)(value*1000000);
@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;
@Override
protected boolean isRouteDisplayed()
// TODO Auto-generated method stub
return false;
public class MonOverlay extends ItemizedOverlay<OverlayItem>
List<GeoPoint> points = new ArrayList<GeoPoint>();
public MonOverlay(Drawable arg0)
super(boundCenterBottom(arg0));
// TODO Auto-generated constructor stub
@Override
protected OverlayItem createItem(int i)
GeoPoint point = points.get(i);
return new OverlayItem(point,"titre","description");
@Override
public int size()
return points.size();
public void addPoint (GeoPoint point)
this.points.add(point);
populate();
这是 Setting.java，我想将 s1 = num.getText().toString(); 传递给 MainActivity.java
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class setting extends Activity
Button sauvg;
EditText num;
String s1;
@Override
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.setting);
sauvg = (Button)findViewById(R.id.ok);
num = (EditText)findViewById(R.id.editText1);
sauvg.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View v)
Intent t = new Intent(setting.this, MainActivity.class);
s1 = num.getText().toString();
t.putExtra("label",s1);
startActivity(t);
// TODO Auto-generated method stub
);
【问题讨论】：
能否提供MainActivity代码？ 我编辑了问题MainActivity 的第 28 行发生了什么？您正在将 null 传递给方法
对不起，我没听懂你的意思。请给我解释一下
【参考方案1】：
错误在这里：
public class MainActivity extends MapActivity
String num;
TextView view = new TextView(this); // <- HERE
你不能在那里创建视图，但你应该在onCreate方法中移动创建，像这样：
公共类 MainActivity 扩展 MapActivity
String num;
TextView view;
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.view = new TextView(this);
Bundle extra = getIntent().getExtras();
注意变量名：我看到你有2个叫做“view”，这不是错误（一个是onCreate中的局部变量，另一个是实例变量）但很容易出错。
顺便说一句，您不能直接访问其他 Activity 中的 TextView。如果你想在活动之间共享数据，你应该使用 Intents 或 Message&Handler
编辑
如果 MainActivity 是您的应用启动时要启动的第一个 Activity，我想您的应用会崩溃。发生这种情况是因为您应该在使用前检查调用意图是否有额外内容，如下所示：
Bundle extra = getIntent().getExtras();
if (extra != null)
num = extra.getString("label");
【讨论】：
它对我有帮助，但我无法从其他类中提取我的 cariable !! 我又编辑了一次我的问题。请帮我传递变量，谢谢以上是关于Android 错误：android.widget.TextView.<init>的主要内容，如果未能解决你的问题，请参考以下文章
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