Question

我只为照片构建自定义图库。我用这个类从sdcard拍照：

public class Photos {
public static final String PHOTO_BUCKET_NAME =
    Environment.getExternalStorageState().toString() + "/DCIM/Camera";
public static final int PHOTO_BUCKET_ID = getBucketId(PHOTO_BUCKET_NAME);

public static int getBucketId(String path) {
    return path.toLowerCase().hashCode();
}

public static List<String> getPhotos(Context context) {
    final String[] projection = {MediaStore.Images.Media.DATA};
    final String selection = MediaStore.Images.Media.BUCKET_ID;
    Cursor c = context.getContentResolver().query(Images.Media.EXTERNAL_CONTENT_URI, projection, selection, null, null);
    List<String> result = new ArrayList<String>(c.getCount());
    if (c.moveToFirst()) {
        int dataColumn = c.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        do {
            String data = c.getString(dataColumn);
            result.add(data);
        } while (c.moveToNext());
    }
    c.close();
    return result;
}

将适配器设置为gallery：

public class ImageAdapter extends BaseAdapter {
    int GalItemBg;
    private Context mContext;
    private List<String> photoList;

    public ImageAdapter(Context c) {
        mContext = c;
        photoList = Photos.getPhotos(c);
        TypedArray typArray = obtainStyledAttributes(R.styleable.GalleryTheme);
        GalItemBg = typArray.getResourceId(R.styleable.GalleryTheme_android_galleryItemBackground, 0);
        typArray.recycle();
    }

    @Override
    public int getCount() {
        return photoList.size();
    }

    @Override
    public Object getItem(int position) {
        return position;
    } 

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView i = new ImageView(mContext);

        Bitmap bm = BitmapFactory.decodeFile(photoList.get(position));
        i.setImageBitmap(bm);
        i.setLayoutParams(new Gallery.LayoutParams(80,70));
        i.setScaleType(ImageView.ScaleType.FIT_XY);
        i.setBackgroundResource(GalItemBg);

        return i;
    }
}

} 没什么特别的。当我运行我的应用程序时，一切都很好。之后，我启动相机并拍摄一些照片，这次我的应用程序在后台运行。当我回到我的应用程序时，我需要看到新照片。怎么做？

尝试：在onResume方法中更新适配器，如下所示：

Gallery g;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    g = (Gallery) findViewById(R.id.gallery);
    g.setAdapter(new ImageAdapter(this));
}
 @Override
public void onResume() {
    g.setAdapter(new ImageAdapter(this));
}

应用程序崩溃。可能是我做错了什么？

logcat的：

02-09 08:12:33.719: ERROR/AndroidRuntime(276): Uncaught handler: thread main exiting due to uncaught exception
02-09 08:12:34.129: ERROR/AndroidRuntime(276): java.lang.RuntimeException: Unable to resume activity {ru.home.tabexample/ru.home.tabexample.TabAct}: java.lang.RuntimeException: Unable to resume activity {ru.home.tabexample/ru.home.tabexample.FirstTab}: android.app.SuperNotCalledException: Activity {ru.home.tabexample/ru.home.tabexample.FirstTab} did not call through to super.onResume()
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2950)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2965)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2516)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.access$2200(ActivityThread.java:119)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.os.Looper.loop(Looper.java:123)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.main(ActivityThread.java:4363)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at java.lang.reflect.Method.invokeNative(Native Method)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at java.lang.reflect.Method.invoke(Method.java:521)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at dalvik.system.NativeStart.main(Native Method)
02-09 08:12:34.129: ERROR/AndroidRuntime(276): Caused by: java.lang.RuntimeException: Unable to resume activity {ru.home.tabexample/ru.home.tabexample.FirstTab}: android.app.SuperNotCalledException: Activity {ru.home.tabexample/ru.home.tabexample.FirstTab} did not call through to super.onResume()
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2950)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:170)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.LocalActivityManager.dispatchResume(LocalActivityManager.java:518)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityGroup.onResume(ActivityGroup.java:58)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1149)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.Activity.performResume(Activity.java:3763)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2937)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     ... 12 more
02-09 08:12:34.129: ERROR/AndroidRuntime(276): Caused by: android.app.SuperNotCalledException: Activity {ru.home.tabexample/ru.home.tabexample.FirstTab} did not call through to super.onResume()
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.Activity.performResume(Activity.java:3765)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2937)
02-09 08:12:34.129: ERROR/AndroidRuntime(276):     ... 18 more

Answer 1

你必须在onResume方法中调用super.onResume。

您可以在例外消息中看到此消息：android.app.SuperNotCalledException: Activity {ru.home.tabexample/ru.home.tabexample.FirstTab} did not call through to super.onResume()

活动基类还使用onResume方法重新初始化东西。如果在类中实现它但忽略了super.onResume（）调用，则无法在基类中进行初始化。

如何将我的应用与照片同步

1 个答案: