致命異常：Android開發的主要錯誤

Question

錯誤：

02-19 21:28:52.920: E/AndroidRuntime(17041): FATAL EXCEPTION: main
02-19 21:28:52.920: E/AndroidRuntime(17041): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.gamecik/com.example.gamecik.MainActivity}: java.lang.ClassCastException: com.google.android.gms.ads.AdView cannot be cast to android.widget.LinearLayout
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2304)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2358)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread.access$700(ActivityThread.java:165)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1326)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.os.Handler.dispatchMessage(Handler.java:99)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.os.Looper.loop(Looper.java:137)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread.main(ActivityThread.java:5450)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at java.lang.reflect.Method.invokeNative(Native Method)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at java.lang.reflect.Method.invoke(Method.java:525)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at dalvik.system.NativeStart.main(Native Method)
02-19 21:28:52.920: E/AndroidRuntime(17041): Caused by: java.lang.ClassCastException: com.google.android.gms.ads.AdView cannot be cast to android.widget.LinearLayout
02-19 21:28:52.920: E/AndroidRuntime(17041):    at com.example.gamecik.MainActivity.onCreate(MainActivity.java:32)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.Activity.performCreate(Activity.java:5369)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
02-19 21:28:52.920: E/AndroidRuntime(17041):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2267)

當我使用Admob代碼時，我的應用程序是錯誤的..如果我刪除了Admob代碼，我的應用程序就很好了。您（如果有意義），請回復並告訴我您需要什么信息，並感謝您的所有幫助

這是我的代碼：

我的活動

package com.example.gamecik;
import com.google.android.gms.ads.AdSize;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;

import android.os.Bundle;
import android.app.Activity;
import android.media.MediaPlayer;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.LinearLayout;


public class MainActivity extends Activity implements OnClickListener {

         private MediaPlayer mp;
         private AdView adView;
         private static final String AD_UNIT_ID = "ca-app-pub-1715534499344773/3123443647";

   @Override
   public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.activity_main);

      adView = new AdView(this);
      adView.setAdUnitId(AD_UNIT_ID);
      adView.setAdSize(AdSize.BANNER);

      LinearLayout layout = (LinearLayout)findViewById(R.id.adView);

      layout.addView(adView);

      AdRequest adRequest = new AdRequest.Builder().build();
      adView.loadAd(adRequest);


      // Add click listeners to all the ImageButtons

      View button1 = findViewById(R.id.sescalbuton);
      View button2 = findViewById(R.id.magnumsilah);
      View button3 = findViewById(R.id.Button03); 
      View button4 = findViewById(R.id.Button02);  
      button1.setOnClickListener(this);
      button2.setOnClickListener(this);
      button3.setOnClickListener(this);
      button4.setOnClickListener(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;
   }

   // Required method if OnClickListener is implemented

   @Override
   public void onClick(View v) {

      // Find which ImageButton was pressed and take appropriate action

      switch(v.getId()){

         // The cow button
         case R.id.sescalbuton:
             mp = MediaPlayer.create(this, R.raw.ak47);
         break;

         // The duck button
         case R.id.magnumsilah:
             mp = MediaPlayer.create(this, R.raw.magnum);
         break;

         // The sheep button                
         case R.id.Button03:
             mp = MediaPlayer.create(this, R.raw.shotgun);
         break;

         // The uzi               
         case R.id.Button02:
             mp = MediaPlayer.create(this, R.raw.uzi);
         break;

      } 

      mp.seekTo(0);
      mp.start();
   }
}

我的XML代碼：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:ads="http://schemas.android.com/apk/lib/com.google.android.gms.ads"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/wood"
    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" >

    <Button
        android:id="@+id/sescalbuton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/shotgun"
        android:layout_below="@+id/magnumsilah"
        android:background="@drawable/ak47" />

    <Button
        android:id="@+id/Button03"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/sescalbuton"
        android:layout_centerHorizontal="true"
        android:background="@drawable/sohtgun" />

    <Button
        android:id="@+id/Button02"
        android:layout_width="150dp"
        android:layout_height="110dp"
        android:layout_above="@+id/sescalbuton"
        android:layout_alignRight="@+id/sescalbuton"
        android:background="@drawable/guns" />

     <com.google.android.gms.ads.AdView 
         xmlns:ads="http://schemas.android.com/apk/res-auto"
         android:id="@+id/adView"
                         android:layout_width="wrap_content"
                         android:layout_height="wrap_content"
                         ads:adUnitId="ca-app-pub-1715534499344773/3123443647"
                         ads:adSize="BANNER"/>

     <ImageView
         android:id="@+id/imageView1"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignLeft="@+id/adView"
         android:layout_alignTop="@+id/adView"
         android:layout_marginTop="28dp"
         android:src="@drawable/supperweapon" />

     <Button
         android:id="@+id/magnumsilah"
         android:layout_width="150dp"
         android:layout_height="100dp"
         android:layout_alignLeft="@+id/imageView1"
         android:layout_below="@+id/imageView1"
         android:background="@drawable/magnum" />

</RelativeLayout>

請幫助我...什么問題？

Answer 1

如果我理解正確，鑄造不是您唯一的問題。 您正在嘗試將AdView添加到活動XML中不存在的LinearLayout中。 但是，相反，您在XML中添加了AdView，並且還動態地啟動了AdView，這沒有任何意義。 將您的onCreate（..）代碼更改為以下內容：

@Override
public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.activity_main);

  adView = (AdView) findViewById(R.id.adView);
  adView.setAdUnitId(AD_UNIT_ID);
  adView.setAdSize(AdSize.BANNER);

  AdRequest adRequest = new AdRequest.Builder().build();
  adView.loadAd(adRequest);

  //.... rest of your onCreate() code
}

Answer 2

查找布局文件中是否存在R.id.adview。 它不是LinearLayout，但是您正在嘗試將其強制轉換為一個。 這就是為什么它崩潰了。 可能是AdView？

Answer 3

問題似乎在這里，

LinearLayout layout = (LinearLayout)findViewById(R.id.adView);

我相信您會嘗試將您的AdView布局轉換為線性布局。

將R.id.adView更改為LinearLayout的ID。 如果不是這種情況，也請發布您的布局xml。

Answer 4

更改位置后嘗試清潔項目。 這對我有用！