这是我的 java 代码，用于在循环中通过 Php 从 Mysql 加载标题、描述、日期和图像。除图像外，一切都完美加载。当我加载图像时，加载对话框显示，我只能在背景中看到一张图像，但加载对话框仍在出现。我是 android 新手，所以我需要像您这样的专家帮助。
Java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Dialog;
import android.app.Fragment;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
public class News_events extends Fragment {
private String jsonResult;
private String url = "http://192.168.2.7/crescentnews/select.php";
HttpPost httppost;
StringBuffer buffer;
HttpResponse response;
HttpClient httpclient;
List<NameValuePair> nameValuePairs;
ProgressDialog dialog = null;
ImageView img;
Bitmap bitmap;
ProgressDialog pDialog;
InputStream is=null;
String result=null;
String line=null;
int code;
public News_events(){}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_news_events, container, false);
accessWebService();
return rootView;
}
// Async Task to access the web
private class JsonReadTask extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(1);
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(params[0]);
try {
httppost.setEntity(new UrlEncodedFormEntity(nameValuePair));
HttpResponse response = httpclient.execute(httppost);
jsonResult = inputStreamToString(
response.getEntity().getContent()).toString();
}
catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private StringBuilder inputStreamToString(InputStream is) {
String rLine = "";
StringBuilder answer = new StringBuilder();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
while ((rLine = rd.readLine()) != null) {
answer.append(rLine);
}
}
catch (IOException e) {
// e.printStackTrace();
Toast.makeText(getActivity().getApplicationContext(),
"Error..." + e.toString(), Toast.LENGTH_LONG).show();
}
return answer;
}
@Override
protected void onPostExecute(String result) {
display();
}
}// end async task
public void accessWebService() {
JsonReadTask task = new JsonReadTask();
// passes values for the urls string array
task.execute(new String[] { url });
}
// build hash set for list view
public void display() {
try {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("news_details");
LinearLayout MainLL= (LinearLayout)getActivity().findViewById(R.id.newslayout);
//LinearLayout headLN=(LinearLayout)findViewById(R.id.headsection);
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
final String head = jsonChildNode.optString("title");
final String details = jsonChildNode.optString("text");
final String date = jsonChildNode.optString("date");
final String image = jsonChildNode.optString("img");
//final String time = jsonChildNode.optString("time");
//img = new ImageView(this.getActivity());
//new LoadImage().execute("http://192.168.2.7/crescentnews/images/"+image);
img = new ImageView(this.getActivity());
LoadImage ldimg=new LoadImage();
ldimg.setImage(img);
ldimg.execute("http://192.168.2.7/crescentnews/images/"+image);
TextView headln = new TextView(this.getActivity());
headln.setText(head); // News Headlines
headln.setTextSize(20);
headln.setTextColor(Color.BLACK);
headln.setGravity(Gravity.CENTER);
headln.setBackgroundResource(R.drawable.menubg);
headln.setPadding(10, 20, 10, 0);
headln.setWidth(100);
headln.setClickable(true);
headln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
//Toast.makeText(getBaseContext(), head, Toast.LENGTH_SHORT).show();
Intent intent = new Intent(getActivity().getApplicationContext(),MainActivity.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
// intent.putExtra("time",time.toString());
startActivity(intent);
}
});
ImageView photo=new ImageView(this.getActivity());
//dateln.setBackgroundColor(Color.parseColor("#f20056"));
photo.setBackgroundColor(Color.parseColor("#000000"));
photo.setPadding(0, 0, 10, 10);
photo.setClickable(true);
// Drawable drawable = LoadImageFromWebOperations("http://192.168.2.7/crescentnews/images/"+pic);
// userpic.setImageDrawable(drawable);
TextView dateln = new TextView(this.getActivity());
dateln.setText(date); // News Headlines
dateln.setTextSize(12);
dateln.setTextColor(Color.BLACK);
dateln.setGravity(Gravity.RIGHT);
//dateln.setBackgroundColor(Color.parseColor("#f20056"));
dateln.setBackgroundColor(0x00000000);
dateln.setPadding(0, 0, 10, 10);
dateln.setWidth(100);
dateln.setClickable(true);
dateln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(), MainActivity.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
// intent.putExtra("time",time.toString());
startActivity(intent);
}
});
View sep=new View(this.getActivity());
sep.setBackgroundColor(Color.parseColor("#252525"));
sep.setMinimumHeight(10);
TextView detailsln = new TextView(this.getActivity());
detailsln.setText(details); // News Details
detailsln.setTextSize(12);
detailsln.setTextColor(Color.BLACK);
detailsln.setGravity(Gravity.LEFT);
detailsln.setPadding(10, 10, 10, 10);
MainLL.addView(headln);
MainLL.addView(dateln);
MainLL.addView(photo);
MainLL.addView(img);
MainLL.addView(detailsln);
MainLL.addView(sep);
detailsln.setClickable(true);
detailsln.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(getActivity().getApplicationContext(), MainActivity.class);
intent.putExtra("head",head.toString());
intent.putExtra("details",details.toString());
intent.putExtra("date",date.toString());
// intent.putExtra("time",time.toString());
startActivity(intent);
}
});
}
} catch (JSONException e) {
Toast.makeText(getActivity().getApplicationContext(), "Error" + e.toString(),
Toast.LENGTH_SHORT).show();
}
}
private class LoadImage extends AsyncTask<String, String, Bitmap> {
ImageView img;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading Image ....");
pDialog.show();
}
public void setImage(ImageView img ){
this.img=img;
}
protected Bitmap doInBackground(String... args) {
try {
bitmap = BitmapFactory.decodeStream((InputStream)new URL(args[0]).openStream());
}
catch (Exception e) { e.printStackTrace(); }
return bitmap;
}
protected void onPostExecute(Bitmap image) {
if(image != null){
img.setImageBitmap(image);
pDialog = new ProgressDialog(getActivity());
pDialog.dismiss();
}
pDialog.dismiss();
}
}
最佳答案
您的代码似乎没问题。
还要检查一些选项，例如 volley
尝试以下内容
private class LoadImage extends AsyncTask<String, String, Bitmap> {
ImageView img;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading Image ....");
pDialog.show();
}
public void setImage(ImageView img ){
this.img=img;
}
protected Bitmap doInBackground(String... args) {
try {
bitmap = BitmapFactory.decodeStream((InputStream)new URL(args[0]).openStream());
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
protected void onPostExecute(Bitmap image) {
if(image != null){
img.setImageBitmap(image);
}
pDialog.dismiss();
}
}
调用这个
img = new ImageView(this.getActivity());
LoadImage ldimg=new LoadImage();
ldimg.setImage(img);
ldimg.execute("http://192.168.2.7/crescentnews/images/"+image);
解雇dialog显示 dialog在 for loop 之前只有一次并在 for loop 之后关闭它
希望对你有帮助:)
关于java - 从php mysql循环加载图像时对话框不断出现，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27653480/