Java NullPointer使用imageadapter将远程图像加载到android gallery
您好，我正在尝试将图像从服务器加载到图库中，但始终出现以下错误：Java NullPointer使用imageadapter将远程图像加载到android gallery,java,android,Java,Android,您好，我正在尝试将图像从服务器加载到图库中，但始终出现以下错误： 04-28 00:54:47.596: W/dalvikvm(715): threadid=1: thread exiting with uncaught exception (group=0x4001d800) 04-28 00:54:47.608: E/AndroidRuntime(715): FATAL EXCEPTION: main 04-28 00:54:47.608: E/AndroidRuntime(715): ja
04-28 00:54:47.596: W/dalvikvm(715): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
04-28 00:54:47.608: E/AndroidRuntime(715): FATAL EXCEPTION: main
04-28 00:54:47.608: E/AndroidRuntime(715): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.plateamobile/com.plateamobile.ProdDetails}: java.lang.NullPointerException
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.os.Handler.dispatchMessage(Handler.java:99)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.os.Looper.loop(Looper.java:123)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.main(ActivityThread.java:4627)
04-28 00:54:47.608: E/AndroidRuntime(715): at java.lang.reflect.Method.invokeNative(Native Method)
04-28 00:54:47.608: E/AndroidRuntime(715): at java.lang.reflect.Method.invoke(Method.java:521)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
04-28 00:54:47.608: E/AndroidRuntime(715): at dalvik.system.NativeStart.main(Native Method)
04-28 00:54:47.608: E/AndroidRuntime(715): Caused by: java.lang.NullPointerException
04-28 00:54:47.608: E/AndroidRuntime(715): at com.plateamobile.ProdDetails.set_info(ProdDetails.java:138)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.plateamobile.ProdDetails.onCreate(ProdDetails.java:49)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
04-28 00:54:47.608: E/AndroidRuntime(715): ... 11 more
package com.plateamobile;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;
import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.PropertyInfo;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapPrimitive;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.*;
import android.widget.Gallery.LayoutParams;
public class ProdDetails extends Activity {
private ImageSwitcher mSwitcher;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.prod_details);
Bundle extras = getIntent().getExtras();
((TextView)findViewById(R.id.prod_name)).setText(extras.getString("name"));
((TextView)findViewById(R.id.price_prod)).setText(new general().formatNumb(extras.getString("price")));
set_info();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.prod_details, menu);
return true;
}
public void set_info(){
ObjConexion object = new ObjConexion();
SoapObject request = new SoapObject(object.NameSpace(), "getProdinfo");
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
Bundle extras = getIntent().getExtras();
PropertyInfo idPro =new PropertyInfo();
idPro.setName("id");
idPro.setValue(extras.getString("id"));
idPro.setType(String.class);
request.addProperty(idPro);
envelope.setOutputSoapObject(request);
HttpTransportSE androidHttpTransport = new HttpTransportSE(object.Url());
androidHttpTransport.debug = true;
try {
androidHttpTransport.call("getProdinfo", envelope);
List<SoapPrimitive> response = (List<SoapPrimitive>) envelope.getResponse();
((TextView)findViewById(R.id.commerce)).setText(response.get(0).toString());
((TextView)findViewById(R.id.description)).setContentDescription(response.get(1).toString());
}catch (Exception e) {
e.printStackTrace();
Toast.makeText(this,e.getMessage().toString(),Toast.LENGTH_LONG).show();
}
request = new SoapObject(object.NameSpace(), "getProdImg");
envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
idPro =new PropertyInfo();
idPro.setName("id");
idPro.setValue(extras.getString("id"));
idPro.setType(Integer.class);
request.addProperty(idPro);
envelope.setOutputSoapObject(request);
androidHttpTransport = new HttpTransportSE(object.Url());
androidHttpTransport.debug = true;
ArrayList<SoapObject> imagesList = new ArrayList<SoapObject>();
try {
androidHttpTransport.call("getProdImg", envelope);
List<SoapObject> response = (List<SoapObject>) envelope.getResponse();
for (int cont=0; cont<response.size() ;cont++){
SoapObject responseChild = (SoapObject) response.get(cont);
imagesList.add(responseChild);
}
}catch (Exception e) {
e.printStackTrace();
if (e.getMessage() == null){
Toast.makeText(this,"Error en la conexion",Toast.LENGTH_LONG).show();
}else{
Toast.makeText(this,e.getMessage().toString(),Toast.LENGTH_LONG).show();
}
}
Gallery _gallery_ = (Gallery) findViewById(R.id.images_prod);
if (imagesList!=null){
_gallery_.setAdapter(new ImageAdapter(getApplicationContext(), imagesList));
}else{
Log.e("DEBUGTAG", "Remtoe Image Exception");
}
}
public void goBack(View v){
Intent intent = new Intent(ProdDetails.this, main_win.class);
startActivity(intent);
}
public class ImageAdapter extends BaseAdapter {
/** The parent context */
private Context myContext;
/** URL-Strings to some remote images. */
private ArrayList<SoapObject> pckg_data;
/** Simple Constructor saving the 'parent' context. */
public ImageAdapter(Context c, ArrayList<SoapObject> data) {
this.myContext = c;
this.pckg_data = data;
}
/** Returns the amount of images we have defined. */
public int getCount() { return this.pckg_data.size(); }
/* Use the array-Positions as unique IDs */
public Object getItem(int position) { return position; }
public long getItemId(int position) { return position; }
/** Returns a new ImageView to
* be displayed, depending on
* the position passed. */
public View getView(int position, View convertView, ViewGroup parent) {
ImageView i = new ImageView(this.myContext);
try {
/* Open a new URL and get the InputStream to load data from it. */
URL aURL = new URL(pckg_data.get(position).getPropertyAsString(1));
URLConnection conn = aURL.openConnection();
conn.connect();
InputStream is = conn.getInputStream();
/* Buffered is always good for a performance plus. */
BufferedInputStream bis = new BufferedInputStream(is);
/* Decode url-data to a bitmap. */
Bitmap bm = BitmapFactory.decodeStream(bis);
bis.close();
is.close();
/* Apply the Bitmap to the ImageView that will be returned. */
i.setImageBitmap(bm);
} catch (IOException e) {
Log.e("DEBUGTAG", "Remtoe Image Exception", e);
}
/* Image should be scaled as width/height are set. */
i.setScaleType(ImageView.ScaleType.FIT_CENTER);
/* Set the Width/Height of the ImageView. */
i.setLayoutParams(new Gallery.LayoutParams(150, 150));
return i;
}
/** Returns the size (0.0f to 1.0f) of the views
* depending on the 'offset' to the center. */
public float getScale(boolean focused, int offset) {
/* Formula: 1 / (2 ^ offset) */
return Math.max(0, 1.0f / (float)Math.pow(2, Math.abs(offset)));
}
}
}
package com.platemobile；
导入java.io.BufferedInputStream；
导入java.io.IOException；
导入java.io.InputStream；
导入java.net.HttpURLConnection；
导入java.net.MalformedURLException；
导入java.net.URL；
导入java.net.URLConnection；
导入java.util.ArrayList；
导入java.util.List；
导入org.ksoap2.SoapEnvelope；
导入org.ksoap2.serialization.PropertyInfo；
导入org.ksoap2.serialization.SoapObject；
导入org.ksoap2.serialization.SoapPrimitive；
导入org.ksoap2.serialization.SoapSerializationEnvelope；
导入org.ksoap2.transport.HttpTransportSE；
导入android.os.Bundle；
导入android.app.Activity；
导入android.content.Context；
导入android.content.Intent；
导入android.graphics.Bitmap；
导入android.graphics.BitmapFactory；
导入android.util.Log；
导入android.view.LayoutInflater；
导入android.view.Menu；
导入android.view.view；
导入android.view.ViewGroup；
导入android.widget.*；
导入android.widget.Gallery.LayoutParams；
公共类ProdDetails扩展活动{
专用图像切换器；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.prod_详细信息）；
Bundle extras=getIntent（）.getExtras（）；
（（TextView）findviewbyd（R.id.prod_name））.setText（extras.getString（“name”）；
（（TextView）findviewbyd（R.id.price_prod））.setText（new-general（）.formatNumb（extras.getString（“price”）））；
set_info（）；
}
@凌驾
公共布尔onCreateOptions菜单（菜单）{
getMenuInflater（）.充气（R.menu.prod_详细信息，菜单）；
返回true；
}
公共无效集_info（）{
ObjConexion对象=新的ObjConexion（）；
SoapObject请求=新的SoapObject（object.NameSpace（），“getProdinfo”）；
SoapSerializationEnvelope=新的SoapSerializationEnvelope（SoapEnvelope.VER11）；
Bundle extras=getIntent（）.getExtras（）；
PropertyInfo idPro=新的PropertyInfo（）；
idPro.setName（“id”）；
idPro.setValue（extras.getString（“id”））；
idPro.setType（String.class）；
请求。addProperty（idPro）；
envelope.setOutputSoapObject（请求）；
HttpTransportSE androidHttpTransport=新的HttpTransportSE（object.Url（））；
androidHttpTransport.debug=true；
试一试{
androidHttpTransport.call（“getProdinfo”，信封）；
列表响应=（列表）信封.getResponse（）；
（（TextView）findViewById（R.id.commerce））.setText（response.get（0.toString（））；
（（TextView）findViewById（R.id.description））.setContentDescription（response.get（1.toString（））；
}捕获（例外e）{
e、 printStackTrace（）；
Toast.makeText（例如，getMessage（）.toString（），Toast.LENGTH_LONG）.show（）；
}
request=newsoapobject（object.NameSpace（），“getProdImg”）；
信封=新的SoapSerializationEnvelope（SoapEnvelope.VER11）；
Idro=新属性info（）；
idPro.setName（“id”）；
idPro.setValue（extras.getString（“id”））；
idPro.setType（Integer.class）；
请求。addProperty（idPro）；
envelope.setOutputSoapObject（请求）；
androidHttpTransport=newHttpTransportSE（object.Url（））；
androidHttpTransport.debug=true；
ArrayList imagesList=新的ArrayList（）；
试一试{
androidHttpTransport.call（“getProdImg”，信封）；
列表响应=（列表）信封.getResponse（）；
对于（int cont=0；cont第一次创建应用时，没有调用它的intent
。因此Bundle extras=getIntent（）.getExtras（）；
会导致NullPointerException
将语句括在try
块中
try
{
Bundle extras = getIntent().getExtras();
}
catch(Exception E){
//do nothing
}
但这不是正确的方法
如果要再次调用此活动，我建议您使用onNewIntent（）
方法并将此活动设置为singleTop
（（TextView）findViewById（R.id.price_prod））.setText（new general（）.formatNum（extras.getString（“price”））；我解决了这个问题真正的问题是当我将适配器设置到库时。将getApplicationContext（）
更改为ProdDetails。这