无法解析Android Studio中的符号HttpGet、HttpClient、HttpResponce

Question

我只是复制了http的所有jar文件，但是Android Studio不能导入所有这些jar文件，它给出一个错误:不能解析符号HttpGet、HttpClient、httpresponse。

public class MainActivity extends AppCompatActivity {

ArrayList<Product>  productslist;
ProductAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);


    productslist = new ArrayList<Product>();
    new JSONAsyncTask().execute("http://opencart.codeniques.com/myshop/?route=feed/web_api/products&id=60&key=test123");

    ListView listView = (ListView)findViewById(R.id.list);
    adapter = new ProductAdapter(getApplicationContext(),R.layout.row,productslist);

    listView.setAdapter(adapter);

    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Toast.makeText(getApplicationContext(),productslist.get(position).getName(),Toast.LENGTH_LONG).show();
        }
    });
}

class JSONAsyncTask extends AsyncTask<String,Void,Boolean>{

    ProgressDialog dialog;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        dialog = new ProgressDialog(MainActivity.this);
        dialog.setMessage("Loading, please wait");
        dialog.setTitle("Connecting server");
        dialog.show();
        dialog.setCancelable(false);
    }

    @Override
    protected Boolean doInBackground(String... params) {
        try{
            HttpGet httppost = new HttpGet(params[0]);
            HttpClient httpclient = new DefaultHttpClient();
            HttpResponse response = httpclient.execute(httppost);

            int status = response.getStatusLine().getStatusCode();

            if(status == 200){
                HttpEntity entity = response.getEntity();
                String data = EntityUtils.toString(entity);

                JSONObject jsono = new JSONObject(data);
                JSONArray jarray = jsono.getJSONArray("products");

                for (int i = 0; i < jarray.length(); i++) {
                    JSONObject object = jarray.getJSONObject(i);

                    Product actor = new Product();

                    actor.setId(object.getString("id"));
                    actor.setName(object.getString("name"));
                    actor.setDescription(object.getString("description"));
                    actor.setHref(object.getString("href"));
                    actor.setPrice(object.getString("pirce"));
                    actor.setImage(object.getString("thumb"));
                    actor.setSpecial(object.getString("special"));
                    actor.setRating(object.getString("rating"));

                    productslist.add(actor);
            }
                return  true;
            }
        }catch (JSONException e){
            Log.e("Error :",e.getMessage());
        }catch (ParseException e){
            Log.e("Error :",e.getMessage());
        }catch (IOException e){
            Log.e("Error :",e.getMessage());
        }catch (Exception e){
            Log.e("Error :",e.getMessage());
        }
        return  false;
    }
    @Override
    protected void onPostExecute(Boolean aBoolean) {
        dialog.cancel();
        adapter.notifyDataSetChanged();
        if(aBoolean == false){
            Toast.makeText(getApplicationContext(), "Unable to fetch data from server", Toast.LENGTH_LONG).show();
        }
    }
}}

apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "22.0.1"

defaultConfig {
    applicationId "android.catalyst.com.newjsonarray"
    minSdkVersion 16
    targetSdkVersion 23
    versionCode 1
    versionName "1.0"
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }}}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])

testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.0.1'
compile 'com.android.support:design:23.0.1'}

Answer 1

只需将此添加到依赖项中即可

compile 'org.apache.httpcomponents:httpcore:4.4.1'
compile 'org.apache.httpcomponents:httpclient:4.5'

最后

dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])    
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.0.1'
compile 'com.android.support:design:23.0.1'
compile 'org.apache.httpcomponents:httpcore:4.4.1'
compile 'org.apache.httpcomponents:httpclient:4.5'
}

并添加以下代码：

 android {
    useLibrary 'org.apache.http.legacy'
         }

供资

指定Apache HTTP Legacy library的要求如果应用程序的目标是API level 28（Android 9.0）或更高版本，则必须在AndroidManifest.xml元素中包含以下声明。

 <uses-library
      android:name="org.apache.http.legacy"
      android:required="false" />