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我創建了一個應用程序，允許用戶在外部存儲上創建相冊（文件夾）。現在我試圖從所述目錄中檢索圖像並將其顯示在GridView中。我使用AsyncTask遍歷使用listFiles（）的文件目錄，然後創建一個位圖，一旦我抓住每個圖像，回收它，然後再次使用它。我的問題是，我的GridView沒有顯示任何內容。我已經設置了幾個日誌中斷，LogCat顯示迭代確實發生並且圖像被檢索。這導致我認爲我在我的Adapter類中的某處發生了錯誤，它將位圖綁定到了網格，可能在getView中？或者，也許我錯了。任何幫助我做錯了什麼？我試圖儘可能地對代碼進行評論，而我忽略了不必要的部分。謝謝從GridView中的SD卡目錄加載圖像
public class AlbumGridView extends Activity implements OnItemClickListener {
private GridView sdcardImages;
private ImageAdapter imageAdapter;
private Display display;
private Bitmap bitmap;
private Bitmap b;
File[] imageList;
private static final String TAG = "AlbumGridView";
String path;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.album_view);
//display =
//((Object) getSystemService(Context.WINDOW_SERVICE))).getDefaultDisplay();
path = getIntent().getStringExtra("key");
Toast.makeText(this, path, Toast.LENGTH_SHORT).show();
setupViews();
setProgressBarIndeterminateVisibility(true);
loadImages();
}
protected void onDestroy() {
super.onDestroy();
final GridView grid = sdcardImages;
final int count = grid.getCount();
ImageView v = null;
for (int i = 0; i < count; i++) {
v = (ImageView) grid.getChildAt(i);
((BitmapDrawable) v.getDrawable()).setCallback(null);
}
}
// Set up the GridView
private void setupViews() {
sdcardImages = (GridView) findViewById(R.id.gvAlbumView);
// sdcardImages.setNumColumns(display.getWidth()/95);
sdcardImages.setClipToPadding(false);
sdcardImages.setOnItemClickListener(AlbumGridView.this);
imageAdapter = new ImageAdapter(getApplicationContext());
// imageAdapter.setImageList(path);
sdcardImages.setAdapter(imageAdapter);
}
private void addImage(LoadedImage... value) {
for (LoadedImage image : value) {
imageAdapter.addPhoto(image);
imageAdapter.notifyDataSetChanged();
}
}
// Save Bitmap images to a list and return that list
@Override
public Object onRetainNonConfigurationInstance() {
final GridView grid = sdcardImages;
final int count = grid.getChildCount();
final LoadedImage[] list = new LoadedImage[count];
for (int i = 0; i < count; i++) {
final ImageView v = (ImageView) grid.getChildAt(i);
list[i] = new LoadedImage(
((BitmapDrawable) v.getDrawable()).getBitmap());
}
return list;
}
private void loadImages() {
// TODO Auto-generated method stub
final Object data = getLastNonConfigurationInstance();
if (data == null) {
new LoadImagesFromSDCard().execute();
} else {
final LoadedImage[] photos = (LoadedImage[]) data;
if (photos.length == 0) {
new LoadImagesFromSDCard().execute();
}
for (LoadedImage photo : photos) {
addImage(photo);
}
}
}
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
}
/---------------------------------------- ---------------------------------------------/
//Adapter for the GridView
public class ImageAdapter extends BaseAdapter {
private Context mContext;
private ArrayList<LoadedImage> photos = new ArrayList<LoadedImage>();
private String path;
private Bitmap bitmap;
public ImageAdapter(Context context) {
mContext = context;
}
public void addPhoto(LoadedImage photo) {
photos.add(photo);
}
public int getCount() {
return photos.size();
}
public Object getItem(int position) {
return photos.get(position);
}
public long getItemId(int position) {
return position;
}
/*
* public File[] setImageList(String path) {
*
* //this.path = path; //this.imageList = imageList; //File imagesDir =
* new File(path); //imageList = imagesDir.listFiles();
*
* File imagesDir = new File(path); imageList = imagesDir.listFiles();
* for (File image : imageList) try { bitmap =
* BitmapFactory.decodeStream(image.toURL().openStream()); //use bitmap
* and recycle afterwards LoadedImage lm = new LoadedImage(bitmap);
* this.addPhoto(lm); bitmap.recycle();
*
* } catch (IOException e) { e.printStackTrace(); } return imageList;
*
* }
*/
public View getView(int position, View convertView, ViewGroup parent) {
final ImageView imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
} else {
imageView = (ImageView) convertView;
}
imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
imageView.setPadding(2, 2, 2, 2);
// imageView.setImageBitmap(photos.get(position).getBitmap());
try {
imageView
.setImageBitmap(BitmapFactory
.decodeStream(imageList[position].toURL()
.openStream()));
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return imageView;
}
}
/*-------------------------------------------------------------------------*/
//AsyncTask to get the images
class LoadImagesFromSDCard extends AsyncTask<Object, LoadedImage, Object> {
@Override
protected Object doInBackground(Object... arg0) {
// Load images from SD card in Background
// Display each image on the screen
File imagesDir = new File(path);
imageList = imagesDir.listFiles();
for (File image : imageList)
try {
if (bitmap != null) {
bitmap.recycle();
bitmap = null;
}
bitmap = BitmapFactory.decodeStream(image.toURL()
.openStream());
Log.e(TAG, "Grabbed Image " + image.getName());
// use bitmap then recycle after
LoadedImage lm = new LoadedImage(bitmap);
// addImage(lm);
// imageAdapter.addPhoto(lm);
// imageAdapter.setImageList(path);
// imageAdapter.addPhoto(lm);
// imageAdapter.setImageList(path);
// bitmap.recycle();
// addImage(lm);
// imageAdapter.addPhoto(lm);
Log.e(TAG, "Added Image " + lm.toString());
// imageAdapter.setImageList(path);
addImage(lm);
// bitmap.recycle();
// bitmap.recycle();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
沒關係。我想通了:) – 2012-01-06 04:03:10
也許你應該用解決方案更新你的問題，以防其他人遇到同樣的問題，並找到這篇文章。 – eightx2 2012-02-07 13:29:27
問題是什麼？ – jramirez 2012-04-10 21:58:36