无法使用 Picasso 从 url 加载图像？

Question

我正在尝试使用 Picasso 加载图像，但没有渲染。

代码的想法是从设备中选择一个图像。稍后我们将其上传到服务器并展示给用户。

实现了前两部分，但问题是图像没有显示在相应的图像视图中。

这是布局文件-

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
  android:orientation="vertical"

    tools:context=".MainActivity">

    <Button
        android:id="@+id/b_img"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="top"
        android:text="Select image"
      />

    <ImageView
        android:id="@+id/profileImage"
        android:layout_width="match_parent"
        android:layout_height="400dp"
        android:layout_below="@+id/b_img"
        />
</LinearLayout>

MainActivity 类：

public class MainActivity extends AppCompatActivity {


    private Button bSelectImg;
    private StorageReference storageReference;
    private static final int g_img = 1;
    private ProgressDialog progressDialog;
    private ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {....

        storageReference = FirebaseStorage.getInstance().getReference();
        progressDialog = new ProgressDialog(this);
        bSelectImg = (Button)findViewById(R.id.b_img);
        imageView =(ImageView)findViewById(R.id.profileImage);

        bSelectImg.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
         Intent intent= new Intent(Intent.ACTION_PICK);
         intent.setType("image/*");
         startActivityForResult(intent , g_img);
            }
        });
    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode,resultCode,data);

        if(requestCode == g_img && requestCode != RESULT_OK ) {

            Uri uri = data.getData();

            progressDialog.setMessage("uploading.....");
            progressDialog.show();

            StorageReference filepath = storageReference.child("Photos").child(uri.getLastPathSegment());

            filepath.putFile(uri).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                @Override
                public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {

                    Task<Uri> downloadUrl = storageReference.getDownloadUrl();

                    Log.i("urlimagexcx",""+downloadUrl);

                    Picasso.with(MainActivity.this)
                            .load(downloadUrl.toString())
                            .into(imageView);

                  Toast.makeText(MainActivity.this,"Upload is don",Toast.LENGTH_LONG).show();
                  progressDialog.dismiss();
             }
           });
        }
    }
}

在app级别的gradle文件中，我使用的是Picasso 2.5.2版-

    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.google.firebase:firebase-core:16.0.8'
    implementation 'com.google.firebase:firebase-auth:16.2.0'
    implementation 'com.google.firebase:firebase-database:16.1.0'
    implementation 'com.google.firebase:firebase-storage:16.1.0'
   // implementation 'com.squareup.picasso:picasso:2.71828'
    implementation 'com.squareup.picasso:picasso:2.5.2'


/// 
 dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'com.google.gms:google-services:4.2.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }

Answer 1

我认为问题是因为您没有正确检索 url。 在 onSuccess 中上传图片后，请尝试这样做：

        filepath.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
                            @Override
                            public void onSuccess(final Uri uri) {
                                String downloadUrl = uri.toString();

                               Picasso.with(MainActivity.this)
                               .load(downloadUrl)
                               .into(imageView);
                            //continue closing brackets here...

经过进一步检查，我注意到您的 onActivityResult 也可能有问题。 这对我来说似乎不对。

   if(requestCode == g_img && requestCode != RESULT_OK ) 

应该是：

   if(requestCode == g_img && resultCode == RESULT_OK )