为什么我使用ActionBar Sherlock和较旧的Android版本在onCreate（）上出现错误？

Question

*更新：我不知道为什么，但删除一些未使用的导入显然已修复它。 *

在较旧的Android版本（例如2.2）上启动我的应用程序时，我会收到以下错误日志...

但我没有在较新的Android版本上收到任何错误。

"at my.package.MainActivity.onCreate(MainActivity.java:12)"

是我的activity_main.xml被加载的地方，所以我认为我的

有问题

<fragment>

的logcat

09-06 14:18:47.037: E/AndroidRuntime(5887): FATAL EXCEPTION: main
09-06 14:18:47.037: E/AndroidRuntime(5887): java.lang.RuntimeException: Unable to start activity ComponentInfo{my.package/my.package.MainActivity}: java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x2
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1768)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread.access$1500(ActivityThread.java:123)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.os.Looper.loop(Looper.java:130)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread.main(ActivityThread.java:3835)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at java.lang.reflect.Method.invokeNative(Native Method)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at java.lang.reflect.Method.invoke(Method.java:507)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at dalvik.system.NativeStart.main(Native Method)
09-06 14:18:47.037: E/AndroidRuntime(5887): Caused by: java.lang.UnsupportedOperationException: Can't convert to dimension: type=0x2
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.content.res.TypedArray.getDimensionPixelSize(TypedArray.java:463)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.view.ViewGroup$MarginLayoutParams.<init>(ViewGroup.java:3692)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.widget.LinearLayout$LayoutParams.<init>(LinearLayout.java:1400)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.widget.LinearLayout.generateLayoutParams(LinearLayout.java:1326)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.widget.LinearLayout.generateLayoutParams(LinearLayout.java:47)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.view.LayoutInflater.rInflate(LayoutInflater.java:625)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.view.LayoutInflater.inflate(LayoutInflater.java:320)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.view.LayoutInflater.inflate(LayoutInflater.java:276)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at com.actionbarsherlock.internal.ActionBarSherlockCompat.setContentView(ActionBarSherlockCompat.java:857)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at com.actionbarsherlock.app.SherlockFragmentActivity.setContentView(SherlockFragmentActivity.java:251)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at my.package.MainActivity.onCreate(MainActivity.java:12)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
09-06 14:18:47.037: E/AndroidRuntime(5887):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)
09-06 14:18:47.037: E/AndroidRuntime(5887):     ... 11 more

MainActivity.java

package my.package;

import android.os.Bundle;
import com.actionbarsherlock.app.SherlockFragmentActivity;

public class MainActivity extends SherlockFragmentActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
    }
}

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<fragment
    android:id="@+id/mainFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    class="my.package.MainFragment" />
</LinearLayout>

MainFragment.java

package my.package;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.content.Intent;
import com.actionbarsherlock.app.SherlockFragment;

public class MainFragment extends SherlockFragment {

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_main, container, false);

    Button button = (Button) view.findViewById(R.id.bmibutton1);
    button.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            updateDetail();
        }
    });

    return view;
}

// May also be triggered from the Activity
public void updateDetail() {
    BmiFragment fragment = (BmiFragment) getFragmentManager()
            .findFragmentById(R.id.bmiFragment);

    if (fragment != null && fragment.isInLayout()) {
    } else {
        Intent intent = new Intent(getActivity().getApplicationContext(),
                BmiActivity.class);

        startActivity(intent);
    }
}
}

fragment_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" >

<Button
    android:id="@+id/bmibutton1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"
    android:text="BMI" />

<Button
    android:id="@+id/whtrbutton2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignRight="@+id/bmibutton1"
    android:layout_below="@+id/bmibutton1"
    android:text="WHtR" />

</RelativeLayout>

的AndroidManifest.xml

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

<uses-sdk
    android:minSdkVersion="7"
    android:targetSdkVersion="15" />

<application
    android:icon="@drawable/icon"
    android:label="@string/app_name"
    android:theme="@style/Theme.Sherlock.Light.DarkActionBar" >
    <activity android:name=".MainActivity" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".BmiActivity"
        android:label="@string/title_activity_bmi" >
    </activity>
</application>

</manifest>

Answer 1

我不知道为什么，但删除一些未使用的进口显然已修复它。