带有图像的光标适配器加载很奇怪

Question

我有一个简单的CursorAdapter，可以获取标题和图像。

它显示标题，然后从互联网加载图像。

但是，当我调用图像加载器时，图像加载到错误的位置，并且它开始变得非常疯狂：请参阅此处。

我的完整代码在这里。

适配器RestaurantListActivityCursorAdapter

public class RestaurantListActivityCursorAdapter extends CursorAdapter {
/* Api variables */
String websiteURL   = "http://cicolife.com";
public RestaurantListActivityCursorAdapter(Context context, Cursor cursor) {
super(context, cursor, 0);
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
return LayoutInflater.from(context).inflate(R.layout.activity_main_list_item, parent, false);
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
// Extract properties from cursor
int get_Id = cursor.getInt(cursor.getColumnIndexOrThrow("_id"));
String getTitle = cursor.getString(cursor.getColumnIndexOrThrow("title"));
String getImage = cursor.getString(cursor.getColumnIndexOrThrow("image"));
// Name
TextView listViewTitle = (TextView) view.findViewById(R.id.listViewTitle);
listViewTitle.setText(getTitle);
// Img
ImageView listViewImage = (ImageView) view.findViewById(R.id.listViewImage);
if(getImage != null) {
if (!(getImage.equals(""))) {
String destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+ File.separatorChar+"/Android/data/com.nettport.restaurants/imgs";
File file = new File (destinationPath, getImage);
if (file.exists ()){
Bitmap myBitmap = BitmapFactory.decodeFile(file.getAbsolutePath());
listViewImage.setImageBitmap(myBitmap);
}
else {
String loadImage = websiteURL + "/_cache/" + getImage;
new HttpRequestImageLoadTask(context, loadImage, listViewImage, getImage,"imgs").execute();
}
}
}
}
}

图像加载器HttpRequestImageLoadTask

public class HttpRequestImageLoadTask extends AsyncTask<Void, Void, Bitmap> {
private String url;
private ImageView imageView;
private LinearLayout linearLayout;
private Resources resources;
private Context context;
private String storeDirectory;
private String imageName;
public interface TaskListener {
void onFinished(String result);
}
public HttpRequestImageLoadTask(Context ctx, String url, ImageView imageView, String imgName, String storeDirectory) {
this.context = ctx;
this.url = url;
this.imageView = imageView;
this.imageName = imgName;
this.storeDirectory = storeDirectory;
}
public HttpRequestImageLoadTask(Context ctx, String url, LinearLayout linearLayout, Resources resources, String imgName, String storeDirectory) {
this.context = ctx;
this.url = url;
this.linearLayout = linearLayout;
this.imageName = imgName;
this.storeDirectory = storeDirectory;
}
@Override
protected Bitmap doInBackground(Void... params) {
if (checkIfCacheExists(imageName)) {
String destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data/com.nettport.restaurants/" + storeDirectory;
File file = new File (destinationPath, imageName);
Bitmap myBitmap = BitmapFactory.decodeFile(file.getAbsolutePath());
return myBitmap;
} else {
try {
URL urlConnection = new URL(url);
HttpURLConnection connection = (HttpURLConnection) urlConnection
.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
saveImage(myBitmap);
return myBitmap;
} catch(Exception e){
e.printStackTrace();
}
}
return null;
}
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
if(imageView != null) {
imageView.setImageBitmap(result);
} else {
if(linearLayout != null){
BitmapDrawable background = new BitmapDrawable(resources, result);
linearLayout.setBackground(background);
}
}
}
public boolean checkIfCacheExists(String imgName){
String destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data/com.nettport.restaurants/" + storeDirectory;
File file = new File (destinationPath, imgName);
return file.exists();
}
private void saveImage(Bitmap finalBitmap) {
// Make dir
String destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data/com.nettport.restaurants/" + storeDirectory;
File folder = new File(destinationPath);
try {
if (!folder.exists()) {
// Make Android
destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android";
folder = new File(destinationPath);
if (!folder.exists()) {
folder.mkdir();
}
// Make Android/data
destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data";
folder = new File(destinationPath);
if (!folder.exists()) {
folder.mkdir();
}

// Make Android/data/com.nettport.restaurants
destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data/com.nettport.restaurants";
folder = new File(destinationPath);
if (!folder.exists()) {
folder.mkdir();
}
// Make Android/data/com.nettport.restaurants/storeDirectory
destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+File.separatorChar+"/Android/data/com.nettport.restaurants/" + storeDirectory;
folder = new File(destinationPath);
if (!folder.exists()) {
folder.mkdir();
}
}
} catch (Exception e){
Toast.makeText(context, "Could not create directory:n" + e.toString(), Toast.LENGTH_LONG).show();
}
if(imageName != null) {
File file = new File(destinationPath, imageName);
if (file.exists()) file.delete();
try {
FileOutputStream out = new FileOutputStream(file);
finalBitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
out.flush();
out.close();
} catch (Exception e) {
// Toast.makeText(context, "Cant save imagen" + e.toString(), Toast.LENGTH_LONG).show();
}
}
}
}

Answer 1

您没有在适配器中为ImageView设置任何else条件。我看到这里缺少几个else块。

if(getImage != null) {
if (!(getImage.equals(""))) {
String destinationPath = android.os.Environment.getExternalStorageDirectory().getPath()+ File.separatorChar+"/Android/data/com.nettport.restaurants/imgs";
File file = new File (destinationPath, getImage);
if (file.exists()){
Bitmap myBitmap = BitmapFactory.decodeFile(file.getAbsolutePath());
listViewImage.setImageBitmap(myBitmap);
} else {
String loadImage = websiteURL + "/_cache/" + getImage;
// Add nothing here when the image is being fetched
listViewImage.setImageBitmap(null);
new HttpRequestImageLoadTask(context, loadImage, listViewImage, getImage,"imgs").execute();
}
} else {
// Add an else block here when image is equals ""
listViewImage.setImageBitmap(null);
}
} else {
// Add an else block here when image is null
listViewImage.setImageBitmap(null);
}

在ImageView中加载图像时，您需要在适配器中指定每个可能的组合。

如果您有来自服务器的图像 URL，只需使用 Glide 在缓存中不可用时加载图像即可。