当我按照错误消息运行我的应用程序时，它会给出：
Unfortunately appName has stopped error
我有以下MainActivity.java文件：
package com.shubhammyapp1.myapp1;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.*;
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b = (Button)findViewById(R.id.button1);
b.setOnClickListener((OnClickListener) this);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void onClick(View arg0) {
EditText et1= (EditText)findViewById(R.id.ocinb);
EditText et2= (EditText)findViewById(R.id.ocint);
TextView tv1= (TextView) findViewById(R.id.textView1);
Double ocb=Double.parseDouble(et1.getText().toString());
Double oct=Double.parseDouble(et2.getText().toString());
Double ocr;
ocr=(ocb-oct)*0.15;
tv1.setText("The %OC is"+ocr);
}
}
/ *我的activiti_main.xml * /
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginTop="37dp"
android:text="1.Organic Carbon" />
<LinearLayout
android:id="@+id/linearLayout1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/ocinb"
android:layout_alignRight="@+id/ocinb"
android:layout_marginRight="33dp"
android:orientation="vertical" >
</LinearLayout>
<TextView
android:id="@+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="@+id/ocinb"
android:layout_alignLeft="@+id/textView1"
android:layout_below="@+id/ocinb"
android:layout_marginLeft="36dp"
android:text="B=" />
<EditText
android:id="@+id/ocinb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="@+id/ocint"
android:layout_below="@+id/textView1"
android:layout_marginTop="36dp"
android:layout_toRightOf="@+id/textView6"
android:ems="5"
android:inputType="numberSigned|numberDecimal" />
<EditText
android:id="@+id/ocint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/ocinb"
android:layout_marginTop="36dp"
android:layout_toRightOf="@+id/textView6"
android:ems="5"
android:inputType="numberSigned|numberDecimal" />
<TextView
android:id="@+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/ocinb"
android:layout_alignBottom="@+id/ocinb"
android:layout_alignLeft="@+id/textView1"
android:layout_marginLeft="15dp"
android:text="B=" />
<TextView
android:id="@+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/ocint"
android:layout_alignBottom="@+id/ocint"
android:layout_alignLeft="@+id/textView3"
android:text="T=" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/ocint"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:onClick="show"
android:text="Result" />
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginBottom="55dp"
android:layout_toRightOf="@+id/textView1"
android:text="TextView" />
</RelativeLayout>
/ 我的Androidmanifest.xml文件 /
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.shubhammyapp1.myapp1"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="9"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.shubhammyapp1.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
错误logcat：
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 0 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 1 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 2 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 3 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 4 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 5 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 6 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 7 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 8 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 9 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 10 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 11 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 12 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 13 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 14 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 15 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 16 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 17 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 18 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 19 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 20 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 21 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 22 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 23 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 24 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 25 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 26 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 27 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 28 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 29 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 30 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 31 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 32 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.773: W/dalvikvm(2415): PR_CAPBSET_DROP 33 failed: Invalid argument. Please make sure your kernel is compiled with file capabilities support enabled.
02-14 12:07:36.783: D/dalvikvm(2415): Not late-enabling CheckJNI (already on)
02-14 12:07:37.513: D/AndroidRuntime(2415): Shutting down VM
02-14 12:07:37.513: W/dalvikvm(2415): threadid=1: thread exiting with uncaught exception (group=0x414c4700)
02-14 12:07:37.673: E/AndroidRuntime(2415): FATAL EXCEPTION: main
02-14 12:07:37.673: E/AndroidRuntime(2415): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.shubhammyapp1.myapp1/com.shubhammyapp1.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.shubhammyapp1.MainActivity" on path: DexPathList[[zip file "/data/app/com.shubhammyapp1.myapp1-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.shubhammyapp1.myapp1-2, /system/lib]]
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2137)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread.access$600(ActivityThread.java:141)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.os.Handler.dispatchMessage(Handler.java:99)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.os.Looper.loop(Looper.java:137)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread.main(ActivityThread.java:5103)
02-14 12:07:37.673: E/AndroidRuntime(2415): at java.lang.reflect.Method.invokeNative(Native Method)
02-14 12:07:37.673: E/AndroidRuntime(2415): at java.lang.reflect.Method.invoke(Method.java:525)
02-14 12:07:37.673: E/AndroidRuntime(2415): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
02-14 12:07:37.673: E/AndroidRuntime(2415): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
02-14 12:07:37.673: E/AndroidRuntime(2415): at dalvik.system.NativeStart.main(Native Method)
02-14 12:07:37.673: E/AndroidRuntime(2415): Caused by: java.lang.ClassNotFoundException: Didn't find class "com.shubhammyapp1.MainActivity" on path: DexPathList[[zip file "/data/app/com.shubhammyapp1.myapp1-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.shubhammyapp1.myapp1-2, /system/lib]]
02-14 12:07:37.673: E/AndroidRuntime(2415): at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:53)
02-14 12:07:37.673: E/AndroidRuntime(2415): at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
02-14 12:07:37.673: E/AndroidRuntime(2415): at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
02-14 12:07:37.673: E/AndroidRuntime(2415): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2128)
02-14 12:07:37.673: E/AndroidRuntime(2415): ... 11 more
答案 0 :(得分：2)
我看到很多可能导致错误的事情，所以你应该发布你的logcat，以便我们知道是什么导致了它。但是，我看到肯定会导致错误的一件事。
android:onClick="show"
表示xml中的Button。我会得到MethodNotFoundException，我相信它是，因为您的代码中没有名为show(View view)的方法。如果以这种方式执行，则无需以编程方式设置OnClickListener。
删除onClick()功能和b.setOnClickListener((OnClickListener) this);，然后添加
public void show(View v)
{
// your code for button click here
}
另外，解析时应该进行一些错误检查。例如，这些行
Double ocb=Double.parseDouble(et1.getText().toString());
应该被try/catch包围或者进行其他错误检查，如果您还没有做某事，以防用户输入无效字符（如字母或根本没有）。
答案 1 :(得分：1)
在Android Manifest文件中，更改活动定义
android:name="com.shubhammyapp1.MainActivity"
android:label="@string/app_name"
到
android:name="com.shubhammyapp1.myapp1.MainActivity"
android:label="@string/app_name"
答案 2 :(得分：0)
请注意，logcat明确告诉您问题：找不到类。每当我收到此错误时，它都是由两件事之一引起的：
我的清单文件中类名中的拼写错误。
我的清单文件中包名不正确。
答案 3 :(得分：0)
// try this way
first of all i found some mistake on your activity code when you implements OnClickListener() wrong way to try correct them like this way
public class MyActivity extends Activity implements View.OnClickListener {
private EditText et1;
private EditText et2;
private TextView tv1;
private Button b;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
et1= (EditText)findViewById(R.id.ocinb);
et2= (EditText)findViewById(R.id.ocint);
tv1= (TextView) findViewById(R.id.textView1);
b = (Button)findViewById(R.id.button1);
b.setOnClickListener(this);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void onClick(View arg0) {
Double ocb=Double.parseDouble(et1.getText().toString());
Double oct=Double.parseDouble(et2.getText().toString());
Double ocr;
ocr=(ocb-oct)*0.15;
tv1.setText("The %OC is"+ocr);
}
}