使用Picasso和okhttp以及AsyncTask載入網路圖片
阿新 • • 發佈：2019-01-22
效果：
程式碼地址：
依賴：
compile 'com.squareup.picasso:picasso:2.5.2' compile 'com.squareup.okhttp3:okhttp:3.6.0'
許可權：
<uses-permission android:name="android.permission.INTERNET"/>
程式碼
1.PicassoOne
package com.example.picassoone; import android.app.ProgressDialog; import android.os.AsyncTask; importandroid.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.annotation.Nullable; import android.support.v7.app.AppCompatActivity; import android.util.Log; import android.view.View; import android.view.ViewGroup; import android.widget.AbsListView; import android.widget.BaseAdapter;import android.widget.Button; import android.widget.ImageView; import android.widget.ListView; import android.widget.TextView; import com.squareup.picasso.Picasso; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import java.io.ByteArrayOutputStream; import java.io.IOException;import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.net.HttpURLConnection; import java.net.URL; import java.util.ArrayList; import java.util.List; import okhttp3.OkHttpClient; import okhttp3.Request; import okhttp3.Response; /** * Created by Administrator on 2017/4/15 0015. * 使用Picasso和okhttp以及AsyncTask載入網路圖片 */ public class PicassoOne extends AppCompatActivity implements View.OnClickListener { private static final String TAG = "GsonUtils"; private static final int SUCCESS = 1; private static final int ERROR = 1; private ListView listView; private Button button; private Button asynctask; private ProgressDialog progressDialog; @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.picasso_one); initView(); progressDialog = new ProgressDialog(PicassoOne.this); } private void initView() { listView = (ListView) findViewById(R.id.listView); button = (Button) findViewById(R.id.button); button.setOnClickListener(this); asynctask = (Button) findViewById(R.id.asynctask); asynctask.setOnClickListener(this); } private MyBaseAdapter myBaseAdapter; private MyOnScrollListener myOnScrollListener; private Handler handler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); if (msg.what == SUCCESS) { Log.d(TAG, "SUCCESS"); String json = (String) msg.obj; //伺服器的資料獲取成功 try { String iconUrlTest = new JSONObject(json).getJSONArray("info").getJSONObject(0).getString("icon"); Log.d(TAG, "iconUrlTest=" + iconUrlTest); } catch (JSONException e) { e.printStackTrace(); } List<InfoItem> infoItemList = new ArrayList<>(); try { JSONArray infos = new JSONObject(json).getJSONArray("info"); for (int i = 0; i < infos.length(); i++) { InfoItem infoItem = new InfoItem(); JSONObject info = infos.getJSONObject(i); infoItem.setIcon(info.getString("icon")); infoItem.setName(info.getString("name")); infoItem.setSize(info.getString("size")); infoItemList.add(infoItem); } } catch (JSONException e) { e.printStackTrace(); Log.d(TAG, "JSONException=" + e.toString()); } //使用Picasso展示圖片 myBaseAdapter = null; isUtf8 = false; myBaseAdapter = new MyBaseAdapter(infoItemList); listView.setAdapter(myBaseAdapter); myOnScrollListener = new MyOnScrollListener(); listView.setOnScrollListener(myOnScrollListener); } } }; boolean isUtf8 = false; @Override public void onClick(View v) { switch (v.getId()) { case R.id.button: Log.d(TAG, "button"); //開啟子執行緒 new Thread(new Runnable() { @Override public void run() { String url = "http://mobileapi.72g.com/index.php?tp=andv4/index_new&op=jifen&point=100"; OkHttpClient okHttpClient = new OkHttpClient(); Request request = new Request.Builder() .url(url) .get() .build(); try { Response response = okHttpClient.newCall(request).execute(); // if (response.isSuccessful()) { //獲取資料成功 String json = response.body().string(); Message message = Message.obtain(); message.obj = json; message.what = SUCCESS; handler.sendMessage(message); } } catch (IOException e) { e.printStackTrace(); Log.d(TAG, "IOException=" + e.toString()); } } }).start(); break; case R.id.asynctask: progressDialog.setTitle("loading..."); String url_get = "http://mobileapi.72g.com/index.php?tp=andv4/index_new&op=jifen&point=100"; //使用AsyncTask來處理網路請求 MyAsyncTask myAsyncTask = new MyAsyncTask(); myAsyncTask.execute(url_get); break; } } /** * listview的介面卡 */ class MyBaseAdapter extends BaseAdapter { private List<InfoItem> infoItemList; public MyBaseAdapter(List<InfoItem> infoItemList) { this.infoItemList = infoItemList; } @Override public int getCount() { return infoItemList.size(); } @Override public Object getItem(int i) { return infoItemList.get(i); } @Override public long getItemId(int i) { return 0; } @Override public View getView(int i, View view, ViewGroup viewGroup) { ViewHolder viewHolder = null; if (null == view) { view = getLayoutInflater().inflate(R.layout.list_item, viewGroup, false); viewHolder = new ViewHolder(); viewHolder.name = (TextView) view.findViewById(R.id.name); viewHolder.size = (TextView) view.findViewById(R.id.size); viewHolder.icon = (ImageView) view.findViewById(R.id.icon); view.setTag(viewHolder); } else { viewHolder = (ViewHolder) view.getTag(); } InfoItem infoItem = infoItemList.get(i); String name = infoItem.getName(); //需要把GBK的亂碼轉換成UTF-8 Log.d(TAG, "isUtf8=" + isUtf8); if (!isUtf8) { try { name = new String(name.getBytes("gbk"), "utf-8"); } catch (UnsupportedEncodingException e) { e.printStackTrace(); Log.d(TAG, "UnsupportedEncodingException=" + e.toString()); } } viewHolder.name.setText(name); viewHolder.size.setText(infoItem.getSize()); //picasso展示圖片;fit為圖片的寬高填充父窗體 Picasso.with(viewGroup.getContext()) .load(infoItem.getIcon()) .fit() .placeholder(R.drawable.loading) .into(viewHolder.icon); return view; } } private static class ViewHolder { TextView name; TextView size; ImageView icon; } /** * 當手指快速滑動的時候，Picasso不進行圖片資源的載入展示，可以大大節約記憶體資源 */ class MyOnScrollListener implements AbsListView.OnScrollListener { @Override public void onScrollStateChanged(AbsListView absListView, int i) { Picasso picasso = Picasso.with(absListView.getContext()); //當處於觸控滑動的時候，或者處於停滯的時候 if (i == SCROLL_STATE_IDLE || i == SCROLL_STATE_TOUCH_SCROLL) { picasso.resumeTag(absListView.getContext()); } else { Log.d(TAG, "picasso.pauseTag"); picasso.pauseTag(absListView.getContext()); } } @Override public void onScroll(AbsListView absListView, int i, int i1, int i2) { } } class MyAsyncTask extends AsyncTask<String, Void, List<InfoItem>> { //在準備載入前 @Override protected void onPreExecute() { super.onPreExecute(); progressDialog.show(); } /** * 在後臺執行 * * @param strings * @return */ @Override protected List<InfoItem> doInBackground(String... strings) { try { URL url = new URL(strings[0]); HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection(); urlConnection.setRequestMethod("GET"); InputStream inputStream = urlConnection.getInputStream(); int responseCode = urlConnection.getResponseCode(); Log.d(TAG, "responseCode=" + responseCode); //請求伺服器資料成功 if (responseCode == 200) { //InputStream 轉換成 String ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); int len = 0; byte[] buffers = new byte[1024]; while ((len = inputStream.read(buffers)) != -1) { byteArrayOutputStream.write(buffers, 0, len); } String json = byteArrayOutputStream.toString(); Log.d(TAG, "json=" + json); //解析json資料,儲存到集合中 try { String iconUrlTest = new JSONObject(json).getJSONArray("info").getJSONObject(0).getString("icon"); Log.d(TAG, "iconUrlTest=" + iconUrlTest); } catch (JSONException e) { e.printStackTrace(); } List<InfoItem> infoItemList = new ArrayList<>(); try { JSONArray infos = new JSONObject(json).getJSONArray("info"); for (int i = 0; i < infos.length(); i++) { InfoItem infoItem = new InfoItem(); JSONObject info = infos.getJSONObject(i); infoItem.setIcon(info.getString("icon")); infoItem.setName(info.getString("name")); infoItem.setSize(info.getString("size")); infoItemList.add(infoItem); } //解析json資料成功，返回集合 return infoItemList; } catch (JSONException e) { e.printStackTrace(); Log.d(TAG, "JSONException=" + e.toString()); } } } catch (IOException e) { e.printStackTrace(); Log.d(TAG, "IOException=" + e.toString()); } return null; } /** * 在ui主執行緒中執行 * * @param infoItems */ @Override protected void onPostExecute(List<InfoItem> infoItems) { super.onPostExecute(infoItems); //清空之前的快取 myBaseAdapter = null; isUtf8 = true; if (null != infoItems) { //展示圖片 myBaseAdapter = new MyBaseAdapter(infoItems); listView.setAdapter(myBaseAdapter); progressDialog.dismiss(); myOnScrollListener = new MyOnScrollListener(); listView.setOnScrollListener(myOnScrollListener); } } } }
2.InfoItem資料類
package com.example.picassoone; /** * Created by Administrator on 2017/4/17 0017. */ public class InfoItem { private String name; private String size; private String icon; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSize() { return size; } public void setSize(String size) { this.size = size; } public String getIcon() { return icon; } public void setIcon(String icon) { this.icon = icon; } }
佈局
1.主介面<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <Button android:id="@+id/button" android:layout_width="match_parent" android:layout_height="60dp" android:text="開啟子執行緒載入資料"/> <Button android:id="@+id/asynctask" android:layout_width="match_parent" android:layout_height="60dp" android:text="使用asynctask載入資料"/> <ListView android:id="@+id/listView" android:layout_width="match_parent" android:layout_height="match_parent" /> </LinearLayout>
2listview條目介面
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <TextView android:id="@+id/name" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="name"/> <TextView android:id="@+id/size" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="size"/> <ImageView android:id="@+id/icon" android:layout_width="match_parent" android:layout_height="150dp" /> </LinearLayout>
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