Android Picasso - 图片无法加载到listview

Question

出于某种原因，当使用Picasso库从服务器检索图像URL时，无法将图像加载到列表视图但是，imageURL确实传递给了PicassoClient类。有10个图像，每个图像的大小约为20kB。

仅供参考，我已提到许多例子，但问题无法解决。请提供一些建议，说明如何解决这些问题。

search activity.Java

public class searchActivity extends AppCompatActivity{
final static String urlAddress = "http://10.0.2.2/Herb/herblist.php"; 
ListView lv = (ListView) findViewById(R.id.HerbListView);

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_search);
    Downloader dl = new Downloader(searchActivity.this, urlAddress, lv);
    dl.execute();
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            startActivity(new Intent(searchActivity.this, searchDetail.class));
        }
    });
}

}

data parser.Java

public class DataParser extends AsyncTask<Void,Void,Integer> {
Context c;
String jsonData;
ListView lv;
ProgressDialog pd;
ArrayList<Herb> herb=new ArrayList<>();
public DataParser(Context c, String jsonData, ListView lv) {
    this.c = c;
    this.jsonData = jsonData;
    this.lv = lv;
}

@Override
protected void onPostExecute(Integer result) {
    super.onPostExecute(result);
    pd.dismiss();
    ...
    CustomAdapter adapter=new CustomAdapter(c,herb);
    lv.setAdapter(adapter);     
}
private int parseData()
{
    try
    {
        JSONArray ja=new JSONArray(jsonData);
        JSONObject jo=null;
        herb.clear();
        Herb Herb;
        for(int i=0;i<ja.length();i++)
        {
            jo=ja.getJSONObject(i);
            int id=jo.getInt("h_id");
            String name=jo.getString("h_name");
            String imageUrl=jo.getString("h_image");
            Herb=new Herb();
            Herb.setId(id);
            Herb.setName(name);
            Herb.setImageUrl(imageUrl);
            herb.add(Herb);
        }
        return 1;
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return 0;
}

}

custom adapter.Java

public class CustomAdapter extends BaseAdapter {
Context c;
ArrayList<Herb> herbs;
LayoutInflater inflater;
public CustomAdapter(Context c, ArrayList<Herb> herbs) {
    this.c = c;
    this.herbs = herbs;
    inflater= (LayoutInflater) c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    if(convertView==null)
    {
        convertView=inflater.inflate(R.layout.model,parent,false);
    }
    TextView nametxt= (TextView) convertView.findViewById(R.id.herbtitle);
    ImageView img= (ImageView) convertView.findViewById(R.id.thumbnail);

    Herb herb = herbs.get(position);
    nametxt.setText(herb.getName());

    PicassoClient.downloadImage(c,herb.getImageUrl(),img);
    return convertView;
}

}

Picasso client.Java

public class PicassoClient {
public static void downloadImage(Context c, String imageUrl, ImageView img){
    if (imageUrl.length() > 0 && imageUrl != null) {
        Picasso.with(c).load(imageUrl).into(img);
        //Picasso.with(c).setLoggingEnabled(true);
    } else {
        Picasso.with(c).load(R.drawable.ic_menu_gallery).into(img);
    }
}

}

content_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.example.User.herb_recognition_test.searchActivity"
    tools:showIn="@layout/activity_search">
    <ListView
        android:id="@+id/HerbListView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>
</RelativeLayout>

model.hml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="match_parent"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_margin="10dp"
card_view:cardCornerRadius="5dp"
card_view:cardElevation="5dp"
android:layout_height="150dp">
<LinearLayout
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:id="@+id/thumbnail"
        android:padding="10dp"
        android:scaleType="fitXY"
        />
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Name"
        android:id="@+id/herbtitle"
        android:padding="10dp"
        android:textColor="@color/colorAccent"
        android:layout_alignParentLeft="true"
        />
</LinearLayout>
</android.support.v7.widget.CardView>

创建listview时生成错误logcat

D/EGL_emulation: eglMakeCurrent: 0x9cad3880: ver 3 1 (tinfo 0x9ca5e890)
D/EGL_emulation: eglMakeCurrent: 0x9cad3880: ver 3 1 (tinfo 0x9ca5e890)
D/EGL_emulation: eglMakeCurrent: 0x9cad3880: ver 3 1 (tinfo 0x9ca5e890)
.searchActivity: +741ms
W/SurfaceFlinger: couldn't log to binary event log: overflow.
W/Settings: Setting airplane_mode_on has moved from android.provider.Settings.System to android.provider.Settings.Global, returning read-only value.
D/skia: ---- fAsset->read(8192) returned 0
D/skia: --- SkAndroidCodec::NewFromStream returned null

Answer 1

尝试使用它首先键入一行而不调用另一个过程。然后检查它是否有效。

乍一看它看起来应该有效，但你有很多条件，也许其中一个是错的，所以它不允许使用毕加索。

试试这一行。 Picasso.with（YOUR_CONTEXT）.load（YOUR_URL）.fit（）代入（YOUR_IMAGEVIEW）。

顺便说一句，你错过了fit（）函数。

Answer 2

似乎由于存储图像的服务器的IP地址而出现此问题。我应该将IP地址放在数字（例如192.168.x.x）而不是localhost。