Android Java - Glide 在自定义适配器中不起作用

Question

我试图使用Glide将URL中的图像放入自定义adpader中的ImageView中。但它向我展示了一个无形的形象。当我尝试从可绘制文件夹中设置图像时，效果很好，但当我使用Glide时，它会消失。我在互联网上看到了另一个例子(Udacity(，它看起来是一样的，但我的应用程序没有显示图像。我找了很多，仍然没有找到解决方案。感谢所有帮助的人

MainActivity.class:

public class MainActivity extends AppCompatActivity {
//Authentication
private FirebaseAuth auth;
private FirebaseAuth.AuthStateListener authStateListener;
//Database
private FirebaseFirestore db;
String photo;
String LOG_TAG = "MainActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Authenticate();
showPosts();
ImageView imageView = findViewById(R.id.image);
}
private void Authenticate(){
//connect the app to Firebase
auth = FirebaseAuth.getInstance();
db = FirebaseFirestore.getInstance();
//check if the user is log in
authStateListener = new FirebaseAuth.AuthStateListener() {
@Override
public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
FirebaseUser user = firebaseAuth.getCurrentUser();
if (user == null) {
// Choose authentication providers
List<AuthUI.IdpConfig> providers = Arrays.asList(
new AuthUI.IdpConfig.EmailBuilder().build(),
new AuthUI.IdpConfig.GoogleBuilder().build());
// Create and launch sign-in intent
startActivityForResult(AuthUI.getInstance().createSignInIntentBuilder().setAvailableProviders(providers).build(), 1);
}
}
};
}
public void showPosts(){
final ArrayList<Post> posts = new ArrayList<>();
final PostAdapter postAdapter = new PostAdapter(this, posts);
ListView list = (ListView) findViewById(R.id.posts);
list.setAdapter(postAdapter);
CollectionReference ref = db.collection("posts");
//get post info
ref.limit(25).get().addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
@Override
public void onComplete(@NonNull Task<QuerySnapshot> task) {
for(QueryDocumentSnapshot doc : task.getResult()){
final String text = doc.getString("context");
String userId = doc.getString("userID");
photo = doc.getString("photo");
Log.e(LOG_TAG, photo);
DocumentReference userRef = db.collection("users").document(userId);
//get OP info
userRef.get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
String userFirstName = task.getResult().getString("firstName");
String userLastName = task.getResult().getString("lastName");
postAdapter.add(new Post(text, userFirstName + " " + userLastName, "url"));
}
});
}
}
});
}
public void addPost(View v){
startActivity(new Intent(this, AddPostActivity.class));
finish();
}
@Override
protected void onPause() {
super.onPause();
auth.removeAuthStateListener(authStateListener);
}
@Override
protected void onResume() {
super.onResume();
auth.addAuthStateListener(authStateListener);
}

Post.class:

public class Post {
private String mText;
private String mUserName;
private String mPhotoURL;
public Post(String text, String userName){
mText = text;
mUserName = userName;
}
public Post(String text, String userName, String photoURL){
mText = text;
mUserName = userName;
mPhotoURL = photoURL;
}
public String getText() {
return mText;
}
public String getUserName() {
return mUserName;
}
public String getPhotoURL() {
return mPhotoURL;
}
}

PostAdapter.class:

public PostAdapter(Activity context, ArrayList<Post> posts){
super(context, 0, posts);
}
@NonNull
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View listItemView = convertView;
if(listItemView == null){
listItemView = LayoutInflater.from(getContext()).inflate(R.layout.post_view, parent, false);
}
Post postItem = getItem(position);
TextView text = (TextView) listItemView.findViewById(R.id.textBox);
text.setText(postItem.getText());
TextView id = (TextView) listItemView.findViewById(R.id.userId);
id.setText(postItem.getUserName());
ImageView imageView = (ImageView) listItemView.findViewById(R.id.imageView);
if(postItem.getPhotoURL() != null){
Glide.with(imageView.getContext()).load(postItem.getPhotoURL()).into(imageView);
}else{
imageView.setVisibility(View.GONE);
}
return listItemView;
}

Answer 1

尝试添加侦听器，以便我们了解onLoadFailed回调中的Glide异常。

Glide.with(imageView.getContext())
.load(postItem.getPhotoURL())
.listener(new RequestListener<Drawable>() {
@Override
public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<Drawable> target, boolean isFirstResource) {
Log.e(TAG, "onLoadFailed: called ==" + e);
return false;
}
@Override
public boolean onResourceReady(Drawable resource, Object model, Target<Drawable> target, DataSource dataSource, boolean isFirstResource) {
Log.e(TAG, "onResourceReady: called");
return false;
}
}).into(imageView);

Answer 2

更改：

postAdapter.add(new Post(text, userFirstName + " " + userLastName, "url"));

收件人：

postAdapter.add(new Post(text, userFirstName + " " + userLastName, photo));

我建议您添加日志以查看URL是否为空：

Log.v("PhotoLog", "URL: "+ photo);

Answer 3

我发现了问题。我在ImageView 的宽度和高度中设置了固定值