java - Android 未捕获的异常

Question

09-30 02:32:31.474: D/ddm-heap(214): Got feature list request
09-30 02:32:31.634: D/AndroidRuntime(214): Shutting down VM
09-30 02:32:31.634: W/dalvikvm(214): threadid=3: thread exiting with uncaught exception   (group=0x4001b188)
09-30 02:32:31.634: E/AndroidRuntime(214): Uncaught handler: thread main exiting due to uncaught exception
09-30 02:32:31.654: E/AndroidRuntime(214): java.lang.RuntimeException: Unable to instantiate  activity ComponentInfo{com.mjcet.mjcet/com.mjcet.mjcet.MJCET}: java.lang.ClassNotFoundException: com.mjcet.mjcet.MJCET in loader dalvik.system.PathClassLoader@44e8c820
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2417)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread.access$2200(ActivityThread.java:119)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.os.Handler.dispatchMessage(Handler.java:99)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.os.Looper.loop(Looper.java:123)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread.main(ActivityThread.java:4363)
09-30 02:32:31.654: E/AndroidRuntime(214):  at java.lang.reflect.Method.invokeNative(Native Method)
09-30 02:32:31.654: E/AndroidRuntime(214):  at java.lang.reflect.Method.invoke(Method.java:521)
09-30 02:32:31.654: E/AndroidRuntime(214):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
09-30 02:32:31.654: E/AndroidRuntime(214):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
09-30 02:32:31.654: E/AndroidRuntime(214):  at dalvik.system.NativeStart.main(Native Method)
09-30 02:32:31.654: E/AndroidRuntime(214): Caused by: java.lang.ClassNotFoundException: com.mjcet.mjcet.MJCET in loader dalvik.system.PathClassLoader@44e8c820
09-30 02:32:31.654: E/AndroidRuntime(214):  at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
09-30 02:32:31.654: E/AndroidRuntime(214):  at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
09-30 02:32:31.654: E/AndroidRuntime(214):  at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
09-30 02:32:31.654: E/AndroidRuntime(214):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2409)
09-30 02:32:31.654: E/AndroidRuntime(214):  ... 11 more
09-30 02:32:31.684: I/dalvikvm(214): threadid=7: reacting to signal 3
09-30 02:32:31.684: E/dalvikvm(214): Unable to open stack trace file '/data/anr/traces.txt': Permission denied

以上是我对以下活动LOGINACTIVITY.java的调试输出

package com.agrim.mjcet;
import com.agrim.mjcet.R;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
//import android.widget.TextView;
import android.widget.Button;
import android.widget.EditText;
import android.view.View.OnClickListener;

public class LoginActivity extends Activity {
EditText txtUserName;
EditText txtPassword;
Button btnLogin;
    Button btnCancel;
    public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

   // setting default screen to login.xml

    setContentView(R.layout.main);
    txtUserName=(EditText)this.findViewById(R.id.txtUname);
    txtPassword=(EditText)this.findViewById(R.id.txtPwd);
    btnLogin=(Button)this.findViewById(R.id.btnLogin);
    btnLogin=(Button)this.findViewById(R.id.btnLogin);
    btnLogin.setOnClickListener(new OnClickListener()
    {

        public void onClick(View v) {
            // Switching to Register screen
            if((txtUserName.getText().toString()).equals(txtPassword.getText().toString()))
            {
                Intent myIntent = new Intent(getApplicationContext(),SampleActivity.class);
                startActivityForResult(myIntent, 0); 
            }
                                     }
    }
    );
}
    }

示例活动.java

package com.agrim.mjcet;
import com.agrim.mjcet.R;
import android.app.Activity;
import android.os.Bundle;  
import android.view.View;
import android.widget.TextView;

public class SampleActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Set View to register.xml
    setContentView(R.layout.lol);

    TextView HomeScreen = (TextView) findViewById(R.id.back);


    HomeScreen.setOnClickListener(new View.OnClickListener() {

        public void onClick(View arg0) {
                            // Closing registration screen
            // Switching to Login Screen/closing register screen
            finish();

        }
    });
}

}

这是我的 2 个布局

主文件

<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#000000"
android:stretchColumns="1">
<TableRow>
<TextView 
android:text="@string/user_name" 
android:textColor="#347235"
android:id="@+id/TextView01" 
android:layout_width="wrap_content" 
android:layout_marginLeft="25dip"
android:layout_height="wrap_content">
</TextView>

<EditText 
android:text="" 
android:inputType="text"    
android:id="@+id/txtUname" 
android:layout_weight="0.75"
android:layout_width="wrap_content" 
android:layout_marginRight="10dip"
android:layout_marginBottom="5dip"
android:background="#FFFFFF"
android:layout_height="wrap_content">
</EditText>
</TableRow>


<TableRow>
<TextView 
android:text="@string/password" 
android:textColor="#347235"
android:id="@+id/TextView02" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"
android:layout_marginLeft="25dip">
</TextView>


<EditText 
android:text="" 
android:inputType="textPassword"
android:id="@+id/txtPwd" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"
android:layout_marginRight="10dip"
android:layout_weight="1"
android:background="#FFFFFF"
android:gravity="center">
</EditText>
</TableRow>


<TableRow>

<Button
android:id="@+id/btnLogin"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#FFFFFF"
android:layout_marginTop="25dip"
android:layout_marginLeft="50dip"
android:onClick="onClickMyButton"
android:text="@string/login" />

<Button
android:id="@+id/btnCancel"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#FFFFFF"
android:layout_marginTop="25dip"
android:layout_marginLeft="100dip"
android:layout_marginRight="50dip"
android:text="@string/cancel" />

</TableRow>

<FrameLayout
android:layout_width="wrap_content"
android:layout_height="match_parent" >

<ImageView
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:scaleType="centerInside"
android:src="@drawable/logo_invert" 
android:contentDescription="@drawable/logo_invert"/>

</FrameLayout>

</TableLayout>

最后是 LOL.xml

    <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:background="#000000"
    android:layout_height="fill_parent" >
    <ImageView 
        android:layout_width="fill_parent"
        android:id="@+id/back"
        android:layout_height="match_parent"
        android:scaleType="centerInside"
        android:src="@drawable/lol"
        android:contentDescription="@drawable/lol">
    </ImageView>


    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="138dp"
        android:orientation="vertical"
        android:gravity="bottom" >

         <TextView
             android:id="@+id/TextView02"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_alignParentBottom="true"
             android:layout_centerHorizontal="true"
             android:text="@string/coming_soon"
             android:textColor="#347235" />

    </RelativeLayout>

</FrameLayout>

这是我的 Android Manifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mjcet.mjcet"
android:versionCode="1"
android:versionName="1.0" >

<uses-permission
    android:name="android.permission.INTERNET"></uses-permission>
<uses-sdk android:minSdkVersion="7" 
      android:targetSdkVersion="15"
      android:maxSdkVersion="16" />  
<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    >

    <activity
        android:name="MJCET"
        android:label="welcome to MJCET" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
 <activity android:name=".SampleActivity"></activity>
</application>

</manifest>

我在初始化时强制关闭.. 是的，这是我的第一个 android 应用程序 :)

score 1 · Accepted Answer

1

您需要在 AndroidManifest.xml 中添加 SampleActivity。

于 2012-09-29T21:40:52.253 回答

score 0 · Accepted Answer

0

看起来您的 AndroidManifest.xml 正在声明一个不存在的活动 (MJECT)。

于 2012-09-29T21:40:01.037 回答

score 0 · Accepted Answer

也许还有其他错误，但我首先发现的是，View带有 idback的ImageView. 您尝试访问并将其转换为TextView. 这肯定会导致ClassCastException.

java - Android 未捕获的异常

3 回答 3

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