我有一个带有图像链接的数据库，我该如何从服务器上下载图像？在网格视图中显示它。 好吧，我已经完成了这段代码here 任何人都可以帮助我。
答案 0 :(得分：3)
由于您有URL（图像）列表并希望将它们加载到GridView中，您可以尝试：
答案 1 :(得分：2)
我在HomeActivity.java中使用了以下函数
public void loadGallery() throws Exception{
String jBannerString = executeHttpGet("http://sujanmaharjan.com.np/joomla/index.php?option=com_atomicongallery&folder=root");
// String jBannerString = executeHttpGet("http://localhost/new/himalmag/index.php?option=com_gk");
jBannerString = "{'earthquakes':" + jBannerString;
jBannerString = jBannerString + "}";
JSONArray r_jsBanner = null;
try
{
jObject = new JSONObject(jBannerString);
r_jsBanner = jObject.getJSONArray("earthquakes");
id = new String[r_jsBanner.length()];
thumb_image = new String[r_jsBanner.length()];
main_image = new String[r_jsBanner.length()];
for (int i =0; i < r_jsBanner.length() ; i++){
JSONObject arGallery = r_jsBanner.getJSONObject(i);
id[i]= i+"";
thumb_image[i]=arGallery.getString("thumbnail");
main_image[i]=arGallery.getString("url");
}
} catch(Exception es){
}
Message myMessage=new Message();
Bundle resBundle = new Bundle();
resBundle.putString("status", "SUCCESS");
myMessage.obj=resBundle;
handlerGallery.sendMessage(myMessage);
}
private Handler handlerGallery = new Handler() {
public void handleMessage(Message msg) {
// dialog.dismiss();
GkTab.gkTab.progressBar.setVisibility(View.GONE);
GridView gridGallery = (GridView)findViewById(R.id.gridGallery);
gridGallery.setAdapter(new ImageAdapter(HomeActivity.this,R.layout.gridview , thumb_image,1));
gridGallery.setOnItemClickListener(
new OnItemClickListener()
{
public void onItemClick(AdapterView<?> arg0, View arg1, int position , long id) {
Intent myintent =new Intent(getApplicationContext(), LayoutGallery.class);
myintent.putExtra("position",position);
myintent.putExtra("stringurl", main_image);
startActivity(myintent);
}
});
}
};
public String executeHttpGet(String httpUrl) throws Exception {
BufferedReader in = null;
StringBuffer sb = new StringBuffer("");
try {
/* HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 1000); // Connection timeout
HttpConnectionParams.setSoTimeout(httpParameters, 1000); // Socket timeout
*/
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet();
request.setURI(new URI(httpUrl));
HttpResponse response = client.execute(request);
in = new BufferedReader
(new InputStreamReader(response.getEntity().getContent()));
String line = "";
String NL = System.getProperty("line.separator");
while ((line = in.readLine()) != null) {
sb.append(line + NL);
}
in.close();
// parse(sb.toString());
}
finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
e.getMessage();
}
}
}
return sb.toString();
}
创建新的Activity LayoutGallery.java
public class LayoutGallery extends Activity {
CustomGallery galleryPictureImage;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//makes full screen and takes away title bar
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
//
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth();
int height = width*3/4;
setContentView(R.layout.gallerylayout);
Intent i = getIntent();
// Receiving the Data
int position= i.getIntExtra("position", 0);
String[] stringurl = i.getStringArrayExtra("stringurl");
galleryPictureImage = (CustomGallery)findViewById(R.id.picturegallerynew);
galleryPictureImage.setSpacing(50);
galleryPictureImage.setAdapter(new LazyGalleryAdapter(LayoutGallery.this,stringurl,null,width,height,1));
galleryPictureImage.setSelection(position);
}
}
创建CustomGallery.java
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.Gallery;
public class CustomGallery extends Gallery{
public CustomGallery(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
return super.onFling(e1, e2, 0, velocityY);
}
}
创建gallerylayout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
>
<com.np.sujanmaharjan.gk.CustomGallery
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/picturegallerynew"
android:fadingEdge="none"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:layout_gravity="center"
android:theme="@android:style/Theme.Black.NoTitleBar.Fullscreen" />
</LinearLayout>
创建LazyGalleryAdapter.java
package com.np.sujanmaharjan.gk;
import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;
public class LazyGalleryAdapter extends BaseAdapter{
private Activity activity;
private String[] data;
private static LayoutInflater inflater=null;
private ProgressBar mProgressBar;
public ImageLoader imageLoader;
public int width;
public int height;
public int imgwidth;
private String[] caption;
public int widthStatus=0;
public LazyGalleryAdapter(Activity a, String[] d) {
activity = a;
data=d;
inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader=new ImageLoader(activity.getApplicationContext());
}
public LazyGalleryAdapter(Activity a, String[] d,String[] c,int wid,int h,int mainGallery) {
activity = a;
caption= c;
data=d;
inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader=new ImageLoader(activity.getApplicationContext());
width=wid;
height=h;
if(mainGallery==1)
widthStatus=1; // for main gallery of picture
}
public int getCount() {
return data.length;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
public static class ViewHolder{
public TextView text;
public ImageView image;
public ProgressBar progressBar;
public LinearLayout ProgressContain;
public LinearLayout imageCaptionLayout;
}
public View getView(int position, View convertView, ViewGroup parent) {
View vi=convertView;
ViewHolder holder;
if(convertView==null){
vi = inflater.inflate(R.layout.gallerypage, null);
holder=new ViewHolder();
holder.image=(ImageView)vi.findViewById(R.id.imageGallery);
holder.progressBar = (ProgressBar)vi.findViewById(R.id.idProgressBar);
holder.ProgressContain = (LinearLayout)vi.findViewById(R.id.idProgressContain);
holder.imageCaptionLayout = (LinearLayout)vi.findViewById(R.id.imageCaptionLayout);
holder.text =(TextView)vi.findViewById(R.id.imageCaption);
imgwidth=width;
holder.image.getLayoutParams().width=imgwidth;
holder.image.getLayoutParams().height=imgwidth*2/3;
holder.image.setScaleType(ImageView.ScaleType.FIT_XY);
holder.ProgressContain.getLayoutParams().width=imgwidth;
holder.ProgressContain.getLayoutParams().height=imgwidth*2/3;
holder.ProgressContain.setBackgroundColor(0xFF414141);
vi.setTag(holder);
}
else
holder=(ViewHolder)vi.getTag();
if(caption[position].equals("")){
holder.text.setText("no caption");
holder.text.setVisibility(View.INVISIBLE);
holder.imageCaptionLayout.getBackground().setAlpha(0);
}
else{
holder.imageCaptionLayout.getBackground().setAlpha(100);
holder.text.setText(caption[position]+" ");
holder.text.setVisibility(View.VISIBLE);
}
holder.image.setTag(data[position]);
imageLoader.DisplayImage(data[position], activity, holder.image,holder.ProgressContain);
return vi;
}
}