Java 我的计划部队关闭了。致命异常：请参阅下面的日志和代码

logcat显示按钮不存在，但我没有发现任何错误。 当我单击主活动页面中的手电筒按钮时，应用程序强制关闭。 我是android编程新手。请帮忙

日志：

 02-04 21:36:29.182: E/AndroidRuntime(798): FATAL EXCEPTION: main
02-04 21:36:29.182: E/AndroidRuntime(798): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.iamtheonewhoknocks.toolkit/com.iamtheonewhoknocks.toolkit.FlashlightActivity}: java.lang.IllegalArgumentException: Button does not exist
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.os.Handler.dispatchMessage(Handler.java:99)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.os.Looper.loop(Looper.java:123)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread.main(ActivityThread.java:3683)
02-04 21:36:29.182: E/AndroidRuntime(798):  at java.lang.reflect.Method.invokeNative(Native Method)
02-04 21:36:29.182: E/AndroidRuntime(798):  at java.lang.reflect.Method.invoke(Method.java:507)
02-04 21:36:29.182: E/AndroidRuntime(798):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
02-04 21:36:29.182: E/AndroidRuntime(798):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
02-04 21:36:29.182: E/AndroidRuntime(798):  at dalvik.system.NativeStart.main(Native Method)
02-04 21:36:29.182: E/AndroidRuntime(798): Caused by: java.lang.IllegalArgumentException: Button does not exist
02-04 21:36:29.182: E/AndroidRuntime(798):  at com.android.internal.app.AlertController.setButton(AlertController.java:288)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.AlertDialog.setButton(AlertDialog.java:161)
02-04 21:36:29.182: E/AndroidRuntime(798):  at com.iamtheonewhoknocks.toolkit.FlashlightActivity.onCreate(FlashlightActivity.java:42)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
02-04 21:36:29.182: E/AndroidRuntime(798):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
02-04 21:36:29.182: E/AndroidRuntime(798):  ... 11 more

activity_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:background="#151515"
    android:orientation="horizontal"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:focusable="true"
    tools:context=".MainActivity" >

    <ImageButton
        android:id="@+id/flashButton"
        android:layout_width="60dip"
        android:layout_height="60dip"
        android:background="@drawable/flashlight"
        android:contentDescription="@string/flashlighticon"
        android:drawableTop="@drawable/flashlight" />

    <ImageButton
        android:id="@+id/convertorButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/flashButton"
        android:layout_centerHorizontal="true"
        android:background="@drawable/converter"
        android:contentDescription="@string/convertericon" />

    <ImageButton
        android:id="@+id/mglassButton"
        android:layout_width="60dip"
        android:layout_height="60dip"
        android:layout_alignLeft="@+id/compassButton"
        android:layout_alignTop="@+id/mirrorButton"
        android:background="@drawable/mglass"
        android:contentDescription="@string/mglassicon" />

     <ImageButton
         android:id="@+id/bubbleButton"
         android:layout_width="60dip"
         android:layout_height="60dip"
         android:layout_alignLeft="@+id/convertorButton"
         android:layout_below="@+id/flashButton"
         android:layout_marginTop="87dp"
         android:background="@drawable/bubble"
         android:contentDescription="@string/bubbleicon" />

     <ImageButton
         android:id="@+id/compassButton"
         android:layout_width="60dip"
         android:layout_height="60dip"
         android:layout_above="@+id/mirrorButton"
         android:layout_alignLeft="@+id/flashButton"
         android:background="@drawable/compass"
         android:contentDescription="@string/compassicon" />

     <ImageButton
         android:id="@+id/mirrorButton"
         android:layout_width="60dip"
         android:layout_height="60dip"
         android:layout_alignLeft="@+id/bubbleButton"
         android:layout_below="@+id/bubbleButton"
         android:layout_marginTop="83dp"
         android:background="@drawable/mirror"
         android:contentDescription="@string/mirroricon" />

     <ImageButton
         android:id="@+id/timerButton"
         android:layout_width="60dip"
         android:layout_height="60dip"
         android:layout_above="@+id/bubbleButton"
         android:layout_alignLeft="@+id/calcButton"
         android:background="@drawable/timer"
         android:contentDescription="@string/timericon" />

     <ImageButton
         android:id="@+id/calcButton"
         android:layout_width="60dip"
         android:layout_height="60dip"
         android:layout_above="@+id/mirrorButton"
         android:layout_alignParentRight="true"
         android:background="@drawable/calculator"
         android:contentDescription="@string/calcicon" />

     <TextView
         android:id="@+id/textView1"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignLeft="@+id/flashButton"
         android:layout_below="@+id/flashButton"
         android:layout_marginTop="19dp"
         android:gravity="center"
         android:text="@string/flashlighticon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView4"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignLeft="@+id/compassButton"
         android:layout_below="@+id/compassButton"
         android:layout_marginTop="17dp"
         android:gravity="center"
         android:text="@string/compassicon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView6"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignBaseline="@+id/textView5"
         android:layout_alignBottom="@+id/textView5"
         android:layout_alignRight="@+id/calcButton"
         android:gravity="center"
         android:text="@string/calcicon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView7"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignLeft="@+id/mglassButton"
         android:layout_below="@+id/mglassButton"
         android:layout_marginTop="16dp"
         android:gravity="center"
         android:text="@string/mglassicon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView8"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignBaseline="@+id/textView7"
         android:layout_alignBottom="@+id/textView7"
         android:layout_alignLeft="@+id/mirrorButton"
         android:layout_alignRight="@+id/textView5"
         android:gravity="center"
         android:text="@string/mirroricon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView3"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignBaseline="@+id/textView2"
         android:layout_alignBottom="@+id/textView2"
         android:layout_alignLeft="@+id/timerButton"
         android:layout_alignRight="@+id/timerButton"
         android:gravity="center"
         android:text="@string/timericon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView2"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignBaseline="@+id/textView1"
         android:layout_alignBottom="@+id/textView1"
         android:layout_centerHorizontal="true"
         android:gravity="center"
         android:text="@string/convertericon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

     <TextView
         android:id="@+id/textView5"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignBaseline="@+id/textView4"
         android:layout_alignBottom="@+id/textView4"
         android:layout_alignRight="@+id/textView2"
         android:gravity="center"
         android:text="@string/bubbleicon"
         android:textAppearance="?android:attr/textAppearanceSmall" />

</RelativeLayout>

activity_flashlight.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:background="#000000"
    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=".FlashlightActivity" >

    <ImageButton
        android:id="@+id/btnSwitch"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:background="@drawable/flashlight_off"
        android:contentDescription="@null" />

</RelativeLayout>

}

清单文件

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.iamtheonewhoknocks.toolkit"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <uses-permission android:name="android.permission.CAMERA" />

    <uses-feature android:name="android.hardware.camera" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.iamtheonewhoknocks.toolkit.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>
        <activity
            android:name="com.iamtheonewhoknocks.toolkit.FlashlightActivity"
            android:label="@string/title_activity_flashlight" >
        </activity>
        <activity
            android:name="com.iamtheonewhoknocks.toolkit.CalculatorActivity"
            android:label="@string/title_activity_calculator" >
        </activity>
        <activity
            android:name="com.iamtheonewhoknocks.toolkit.TimerActivity"
            android:label="@string/title_activity_timer" >
        </activity>
        <activity
            android:name="com.iamtheonewhoknocks.toolkit.BubbleActivity"
            android:label="@string/title_activity_bubble" >
        </activity>
    </application>

</manifest>

---

您应该更改此部分

alert.setButton(0,"OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // closing the application
            finish();
        }
    });

到

---

出现错误是因为值0为。

请查看文档中的内容

此方法在API级别3中被弃用。 将setButton（int、CharSequence、android.content.DialogInterface.OnClickListener）与按钮“”一起使用

因此，不应直接传递int（0），而应使用DialogInterface.BUTTON_正数。此外，您还可以直接使用

alert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // closing the application
            finish();
        }
    });

---

FlashlightActivity的第42行是什么？此外，您可能希望尝试清理和重建项目。您是否已在清单文件中添加闪光灯活动？我已尝试清理我的项目。我已添加清单文件。请查看是否有任何更正。

alert.setButton（0

为什么不阅读该方法的文档，因为错误是一个illegalargumentexception，文档很可能定义了该方法的参数的合法值…不客气！如果您愿意，请将其标记为closed。我怎么做？我不熟悉这个。抱歉。很简单，@nandu:在我的answe旁边r应该有一个透明的复选标记。选择该复选标记可将答案标记为已接受（您也可以阅读本主题以进一步了解该过程：）

alert.setButton(0,"OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // closing the application
            finish();
        }
    });

alert.setButton(DialogInterface.BUTTON_POSITIVE,"OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // closing the application
            finish();
        }
    });

alert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int which) {
            // closing the application
            finish();
        }
    });