我的Firebase图片在运行时未显示在我的应用程序上。这是我的文件选择代码：
import android.content.ContentResolver;
import android.content.Intent;
import android.media.Image;
import android.net.Uri;
import android.os.Handler;
import android.support.annotation.NonNull;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.webkit.MimeTypeMap;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.storage.FirebaseStorage;
import com.google.firebase.storage.OnProgressListener;
import com.google.firebase.storage.StorageReference;
import com.google.firebase.storage.StorageTask;
import com.google.firebase.storage.UploadTask;
import com.squareup.picasso.Picasso;
public class lost_file_select extends AppCompatActivity {
private static final int PICK_IMAGE_REQUEST = 1;
private FloatingActionButton mButtonChooseImage;
private Button mButtonUpload;
private EditText mEditTextFileDes;
private ImageView mImageView;
private ProgressBar mProgressBar;
private Uri mImageUri;
private StorageReference mStorageRef;
private DatabaseReference mDatabaseref;
private StorageTask mUploadTask;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_lost_file_select);
mButtonChooseImage = findViewById(R.id.button_choose_image_lost);
mButtonUpload = findViewById(R.id.button_upload_lost);
mEditTextFileDes = findViewById(R.id.edit_text_des_lost);
mImageView = findViewById(R.id.image_view_lost);
mProgressBar = findViewById(R.id.progress_bar_lost);
mStorageRef = FirebaseStorage.getInstance().getReference("uploads");
mDatabaseref = FirebaseDatabase.getInstance().getReference("uploads");
mButtonChooseImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
openImageChooser();
}
});
mButtonUpload.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mUploadTask != null && mUploadTask.isInProgress()) {
Toast.makeText(lost_file_select.this, "Patience, young grasshopper", Toast.LENGTH_SHORT).show();
}else {
uploadFile();
}
}
});
}
private void openImageChooser(){
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(intent, PICK_IMAGE_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null){
mImageUri = data.getData();
mImageView.setImageURI(mImageUri);
}
}
private String getFileExtension(Uri uri){
ContentResolver cR = getContentResolver();
MimeTypeMap mime = MimeTypeMap.getSingleton();
return mime.getExtensionFromMimeType(cR.getType(uri));
}
private void uploadFile(){
if (mEditTextFileDes.getText().toString() != null){
final StorageReference fileRefernce = mStorageRef.child(System.currentTimeMillis() + "." +getFileExtension(mImageUri));
mUploadTask = fileRefernce.putFile(mImageUri)
.addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
@Override
public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
@Override
public void run() {
mProgressBar.setProgress(0);
}
}, 500);
Toast.makeText(lost_file_select.this, "Uploaded successfully", Toast.LENGTH_SHORT).show();
Upload upload = new Upload(mEditTextFileDes.getText().toString().trim(), taskSnapshot.getStorage().getDownloadUrl().toString());
String uploadID = mDatabaseref.push().getKey();
mDatabaseref.child(uploadID).setValue(upload);
}
})
.addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception e) {
Toast.makeText(lost_file_select.this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
})
.addOnProgressListener(new OnProgressListener<UploadTask.TaskSnapshot>() {
@Override
public void onProgress(UploadTask.TaskSnapshot taskSnapshot) {
double progress = (100.0 * taskSnapshot.getBytesTransferred() / taskSnapshot.getTotalByteCount());
mProgressBar.setProgress((int) progress);
}
});
}else{
Toast.makeText(this, "No description written", Toast.LENGTH_SHORT).show();
}
}
}
这是我的上载课程：
public class Upload {
private String mDes;
private String mImageUrl;
public Upload(){
}
public Upload (String des, String imageUrl){
mDes = des;
mImageUrl = imageUrl;
}
public String getDes(){
return mDes;
}
public void setDes(String des){
mDes = des;
}
public String getImageUrl(){
return mImageUrl;
}
public void setImageUrl(String imageUrl){
mImageUrl = imageUrl;
}
}
这是我显示图像的活动的类别：
public class lost extends AppCompatActivity {
private RecyclerView mRecyclerView;
private ImageAdapter mAdapter;
private DatabaseReference mDatabaseRef;
private List<Upload> mUploads;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_lost);
FloatingActionButton fablost = findViewById(R.id.addlost);
fablost.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent lostfileselect = new Intent(lost.this, lost_file_select.class);
startActivity(lostfileselect);
}
});
mRecyclerView = findViewById(R.id.recycler_view_lost);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
mUploads = new ArrayList<>();
mDatabaseRef = FirebaseDatabase.getInstance().getReference("uploads");
mDatabaseRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
for (DataSnapshot postSnapshot : dataSnapshot.getChildren()){
Upload upload = postSnapshot.getValue(Upload.class);
mUploads.add(upload);
}
mAdapter = new ImageAdapter(lost.this, mUploads);
mRecyclerView.setAdapter(mAdapter);
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
Toast.makeText(lost.this, databaseError.getMessage(), Toast.LENGTH_SHORT).show();
}
});
}
}
最后这是我的ImageAdapter类：
import android.content.Context;
import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import com.squareup.picasso.Picasso;
import java.util.List;
public class ImageAdapter extends RecyclerView.Adapter <ImageAdapter.ImageViewHolder> {
private Context mContext;
private List<Upload> mUploads;
public ImageAdapter(Context context, List<Upload> uploads){
mContext = context;
mUploads = uploads;
}
@NonNull
@Override
public ImageViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View v = LayoutInflater.from(mContext).inflate(R.layout.entry, parent, false);
return new ImageViewHolder(v);
}
@Override
public void onBindViewHolder(@NonNull ImageViewHolder holder, int position) {
Upload uploadCurrent = mUploads.get(position);
holder.textViewDes.setText(uploadCurrent.getDes());
Picasso.with(mContext).load(uploadCurrent.getImageUrl()).placeholder(R.mipmap.ic_launcher).fit().centerCrop().into(holder.imageView);
}
@Override
public int getItemCount() {
return mUploads.size();
}
public class ImageViewHolder extends RecyclerView.ViewHolder{
public TextView textViewDes;
public ImageView imageView;
public ImageViewHolder(View itemView) {
super(itemView);
textViewDes = itemView.findViewById(R.id.text_view_description);
imageView = itemView.findViewById(R.id.image_view_upload);
}
}
}
我在Firebase存储中启用了Internet权限，但是占位符图像启动，而不是我要发布的图像。有人可以告诉我错误是什么以及如何解决吗？我是android工作室的新手，所以如果您有答案，请务必清楚解释！