我正在使用 UIL 在列表视图中加载图像。
当我长按列表视图中的图像时，我会显示一个对话框来修改该图片，并使用相机将其替换为新图片。
如果我拍一张新照片，当对话框被关闭时，我的列表视图仍会显示旧图像（因为它已被缓存）。如果我在转到列表视图时关闭并重新启动我的应用程序，那么新图像就在那里。
这就是我设置 UIL 的方式：
// Get singletone instance of ImageLoader
imageLoader = ImageLoader.getInstance();
//set display options for image loader
DisplayImageOptions displayOptions = new DisplayImageOptions.Builder()
.cacheInMemory()
.displayer(new FadeInBitmapDisplayer(500)) //fade in images
.resetViewBeforeLoading()
.build();
//set image loader options
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(this).defaultDisplayImageOptions(displayOptions).build();
// Initialize ImageLoader with configuration.
imageLoader.init(config);
如果我删除.cacheInMemory()一切正常。我只是想知道仅在打开对话框时是否可以清除缓存。我试图myImageView.invalidate()在打开对话框时选择并调用 ImageView，但没有成功。
图像从文件加载：
// Load and display image asynchronously
imageLoader.displayImage(file_prefix + image_path, image);
有什么建议么？
编辑：长按图像时创建上下文菜单的代码，我试图清除那里的缓存：
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
//get info about item selected
AdapterView.AdapterContextMenuInfo info;
try {
// Casts the incoming data object into the type for AdapterView objects.
info = (AdapterView.AdapterContextMenuInfo) menuInfo;
} catch (ClassCastException e) {
// If the menu object can't be cast, logs an error.
Log.e("no info", "bad menuInfo", e);
return;
}
Cursor cursor = (Cursor) getListAdapter().getItem(info.position);
if (cursor == null) {
// For some reason the requested item isn't available, do nothing
return;
}
//remove selected image from cache (if it is an image)
imageUrl = cursor.getString(cursor.getColumnIndex("image_path"));
if (!imageUrl.equalsIgnoreCase("")) {
MemoryCacheUtil.removeFromCache(imageUrl, imageLoader.getMemoryCache());
}
Log.i("imageUrl", imageUrl);
//get defect row ID and text content to pass it to defect activity
defect_row_id = cursor.getLong(cursor.getColumnIndex("_id"));
defect_txt = cursor.getString(cursor.getColumnIndex("defect"));
MenuInflater inflater = getMenuInflater();
Log.i("cursor", DatabaseUtils.dumpCursorToString(cursor));
//set project identifier in context menu header, mapping cursor sequence of values
menu.setHeaderTitle(getString(R.string.select_an_option));
inflater.inflate(R.menu.menu_defect_row, menu);
}
选择菜单项（编辑或删除）时
@Override
public boolean onContextItemSelected(MenuItem item) {
//AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
switch (item.getItemId()) {
case R.id.edit:
//open defect activity with the specified image and defect pre-loaded
Intent editDefectIntent = new Intent(this, DefectActivity.class);
editDefectIntent.putExtra("defect_row_id", defect_row_id);
editDefectIntent.putExtra("imageUrl", imageUrl);
startActivity(editDefectIntent);
return true;
case R.id.delete:
askDeleteConfirm();
return true;
default:
return false;
}
}//onContextItemSelected
编辑：显示图像列表的代码
@Override
public void onResume() {
super.onResume();
//open connection to db
db = new DBAdapter(this);
db.open();
Log.i("DefectListActivity -> onResume", "called");
// get all defects for this unit
defectList = db.getAllDefectsByUnit(unit_id);
// create an array adapter and let it to display our row
defects = new SimpleCursorAdapter(this, R.layout.defect_row, defectList, new String[] { "defect", "image_path" }, new int[] { R.id.defect, R.id.image }, 0);
//set custom view using ViewBinder
SimpleCursorAdapter.ViewBinder binder = new SimpleCursorAdapter.ViewBinder() {
@Override
public boolean setViewValue(View view, Cursor cursor, int columnIndex) {
int placeholder_id = getResources().getIdentifier("placeholder", "drawable", getPackageName());
//get column name
String name = cursor.getColumnName(columnIndex);
//for the thumbnail column,if we have an image replace the placeholder
if ("image_path".equals(name)) {
ImageView image = (ImageView) view.findViewById(R.id.image);
//Bitmap thumbnail;
String image_path = cursor.getString(columnIndex);
Log.i("image_path ->", image_path);
if (!image_path.equalsIgnoreCase("")) {
// Load and display image asynchronously
imageLoader.displayImage(file_prefix + image_path, image);
} else {
image.setImageResource(placeholder_id);
}
return true;
}
//for the defect column, just add the text to the view
if ("defect".equals(name)) {
String defect_text = cursor.getString(columnIndex);
TextView defect_holder = (TextView) view.findViewById(R.id.defect);
defect_holder.setText(defect_text);
return true;
}
return false;
}
};
defects.setViewBinder(binder);
setListAdapter(defects);
}//onResume