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java错误:无法实例化活动组件信息

我在运行应用程序时出现以下错误:

12-14 12:04:42.088: E/AndroidRuntime(331): FATAL EXCEPTION: main
12-14 12:04:42.088: E/AndroidRuntime(331): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.awesomefilebuilderwidget/com.example.awesomefilebuilderwidget.GridViewAdapter}: java.lang.InstantiationException: com.example.awesomefilebuilderwidget.GridViewAdapter
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread.performLaunchActivity(ActivityThread.java:1746)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1854)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread.access$1500(ActivityThread.java:135)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread$H.handleMessage(ActivityThread.java:1041)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.os.Handler.dispatchMessage(Handler.java:99)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.os.Looper.loop(Looper.java:150)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread.main(ActivityThread.java:4333)
12-14 12:04:42.088: E/AndroidRuntime(331):  at java.lang.reflect.Method.invokeNative(Native Method)
12-14 12:04:42.088: E/AndroidRuntime(331):  at java.lang.reflect.Method.invoke(Method.java:507)
12-14 12:04:42.088: E/AndroidRuntime(331):  at com.安卓.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
12-14 12:04:42.088: E/AndroidRuntime(331):  at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:597)
12-14 12:04:42.088: E/AndroidRuntime(331):  at dalvik.system.NativeStart.main(Native Method)
12-14 12:04:42.088: E/AndroidRuntime(331): Caused by: java.lang.InstantiationException: com.example.awesomefilebuilderwidget.GridViewAdapter
12-14 12:04:42.088: E/AndroidRuntime(331):  at java.lang.Class.newInstanceImpl(Native Method)
12-14 12:04:42.088: E/AndroidRuntime(331):  at java.lang.Class.newInstance(Class.java:1409)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.Instrumentation.newActivity(Instrumentation.java:1040)
12-14 12:04:42.088: E/AndroidRuntime(331):  at 安卓.app.ActivityThread.performLaunchActivity(ActivityThread.java:1738)
12-14 12:04:42.088: E/AndroidRuntime(331):  ... 11 more

下面是我的GridViewAdapter类:

package com.example.awesomefilebuilderwidget;

IMPORTS

public class GridViewAdapter extends BaseAdapter {
private Context Context;

// Keep all Images in array list
public ArrayList<Integer> drawables = new ArrayList<Integer>();

CheckBox mCheckBox=null;

// Constructor
public GridViewAdapter(Context c){
    Context = c;
    Log.d("GridViewAdapter", "Constructor is set");

    drawables.add(R.drawable.pattern1);
    Log.d("GridViewAdapter", "pattern1 added");

    drawables.add(R.drawable.pattern2);
    Log.d("GridViewAdapter", "pattern2 added");

    drawables.add(R.drawable.trashcan);
    Log.d("GridViewAdapter", "trashcan added");

    drawables.add(R.drawable.ic_launcher);
    Log.d("GridViewAdapter", "ic_launcher added");
}

public void setCheckBox(CheckBox checkbox){
    mCheckBox=checkbox;
}

@Override
// How many items are in the data set represented by this Adapter
public int getCount() {
    return drawables.size();
}

@Override
// Get the data item associated with the specified position in the
// data set
public Object getItem(int position) {
    return drawables.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

public boolean isSdReadable() {

    boolean mExternalStorageAvailable = false;
    String state = Environment.getExternalStorageState();

    if (Environment.MEDIA_MOUNTED.equals(state)) {
    // We can read and write the media
    mExternalStorageAvailable = true;
    Log.i("isSdReadable", "External storage card is readable.");
    } else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
    // We can only read the media
    Log.i("isSdReadable", "External storage card is readable.");
    mExternalStorageAvailable = true;
    } else {
    // Something else is wrong. It may be one of many other
    // states, but all we need to know is we can neither read nor write
    mExternalStorageAvailable = false;
    }

    return mExternalStorageAvailable;
    }

public Bitmap getThumbnail() {

    final String APP_PATH_SD_CARD = "/TEST/";
    final String APP_THUMBNAIL_PATH_SD_CARD = "thumbnails";
    String filename = "AFBWIcon.png";

    String fullPath = Environment.getExternalStorageDirectory().getAbsolutePath() + APP_PATH_SD_CARD + APP_THUMBNAIL_PATH_SD_CARD;
    Bitmap thumbnail = null;

    // Look for the file on the external storage
    try {
    if (isSdReadable() == true) {
    thumbnail = BitmapFactory.decodeFile(fullPath + "/" + filename);
    }
    } catch (Exception e) {
    Log.e("getThumbnail() on external storage", e.getMessage());
    }

    // If no file on external storage, look in internal storage
    if (thumbnail == null) {
    try {
    File filePath = Context.getFileStreamPath(filename);
    FileInputStream fi = new FileInputStream(filePath);
    thumbnail = BitmapFactory.decodeStream(fi);
    } catch (Exception ex) {
    Log.e("getThumbnail() on internal storage", ex.getMessage());
    }
    }
    return thumbnail;
    }



@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // Try to reuse the views
    ImageView view = (ImageView) convertView;
    @SuppressWarnings("unused")
    boolean checked = (mCheckBox==null)?false:(((CheckBox)  mCheckBox).isChecked());
    // if convert view is null then create a new instance else reuse it
    if (view == null) {
        view = new ImageView(Context);
        Log.d("GridViewAdapter", "new imageView added");
    }
    if(checked = true){
        isSdReadable();
        try {
            FileInputStream in = Context.openFileInput("BitmapImage");
            // Load back the image file to confirm it works
            Bitmap bitmap = BitmapFactory.decodeStream(in);
            view.setImageBitmap(bitmap);
            in.close();
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        // getThumbnail();
        catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    } else {
        Log.e("GridView", "Icons not for use");
    }
    view.setImageResource(drawables.get(position));
    view.setScaleType(ImageView.ScaleType.CENTER_CROP);
    view.setLayoutParams(new 安卓.widget.GridView.LayoutParams(70, 70));
    view.setTag(String.valueOf(position));
    return view;
}

}

这是我的清单:

<manifest xmlns:安卓="http://schemas.安卓.com/apk/res/安卓"
package="com.example.awesomefilebuilderwidget"
安卓:versionCode="1"
安卓:versionName="1.0" >

<uses-sdk
安卓:minSdkVersion="8"
安卓:targetSdkVersion="18" />

<uses-permission 安卓:name="安卓.permission.READ_EXTERNAL_STORAGE" />
<uses-permission 安卓:name="安卓.permission.WRITE_EXTERNAL_STORAGE" />

<application
安卓:allowBackup="true"
安卓:icon="@drawable/ic_launcher"
安卓:label="@string/app_name"
安卓:theme="@style/AppTheme" >

<receiver 安卓:name="com.example.awesomefilebuilderwidget.AFBWidget" 安卓:label="@string/app_name">
<intent-filter>
<action 安卓:name="安卓.appwidget.action.APPWIDGET_UPDATE"/>
</intent-filter>

<meta-data 安卓:name="安卓.appwidget.provider"
安卓:resource="@xml/widget_stuff"/>

</receiver>

<activity 安卓:name="com.example.awesomefilebuilderwidget.WidgetConfig" 安卓:label="@string/app_name">
<intent-filter>
<action 安卓:name="安卓.appwidget.action.APPWIDGET_CONFIGURE"/>

</intent-filter> 

</activity>   

<activity 安卓:name="com.example.awesomefilebuilderwidget.Drag_and_Drop_App" 安卓:label="@string/app_name" 安卓:windowSoftInputMode="stateHidden" 安卓:screenOrientation="portrait"></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.AppInfoAdapter" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.Feedback" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.GridView" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.SendMessageActivity" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.Utilities" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.Personalize" 安卓:label="@string/app_name" ></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.SwipeDetector" 安卓:label="@string/app_name"></activity>
<activity 安卓:name="com.example.awesomefilebuilderwidget.GridViewAdapter" 安卓:label="@string/app_name"></activity>

</application>

</manifest> 

我已经在SOF上四处查看了一下,但还没有找到任何有助于解决这个问题的方法。 是什么导致了这个错误

请注意,在我出现这个错误之前,这一切都很好


共 (2) 个答案

  1. # 1 楼答案

    它会崩溃,因为你在清单中指定了一个适配器类,删除它,你的应用程序就没有默认的启动活动 在舱单上你需要这样的东西:

    <activity android:name=".put your started activity name here"
                  android:label="@string/app_name">
     <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    

    指定所需的活动

  2. # 2 楼答案

    从清单中删除适配器类引用

    只能在清单中添加活动类