如何在ImageView中使用URL引用的图像?
当前回答
在我看来,最适合完成这项任务的现代图书馆是毕加索广场图书馆。它允许通过URL加载图像到ImageView,只需一行代码:
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").into(imageView);
其他回答
你必须先下载图像
public static Bitmap loadBitmap(String url) {
Bitmap bitmap = null;
InputStream in = null;
BufferedOutputStream out = null;
try {
in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);
final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
copy(in, out);
out.flush();
final byte[] data = dataStream.toByteArray();
BitmapFactory.Options options = new BitmapFactory.Options();
//options.inSampleSize = 1;
bitmap = BitmapFactory.decodeByteArray(data, 0, data.length,options);
} catch (IOException e) {
Log.e(TAG, "Could not load Bitmap from: " + url);
} finally {
closeStream(in);
closeStream(out);
}
return bitmap;
}
然后使用Imageview。setImageBitmap将位图设置为ImageView
这是一个迟到的回复,正如上面所建议的AsyncTask将会和谷歌一点后,我发现了一个解决这个问题的方法。
Drawable Drawable = Drawable. createfromstream ((InputStream) new URL(" URL ").getContent(), "src");
imageView.setImageDrawable(可拉的);
这是完整的功能:
public void loadMapPreview () {
//start a background thread for networking
new Thread(new Runnable() {
public void run(){
try {
//download the drawable
final Drawable drawable = Drawable.createFromStream((InputStream) new URL("url").getContent(), "src");
//edit the view in the UI thread
imageView.post(new Runnable() {
public void run() {
imageView.setImageDrawable(drawable);
}
});
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
}
不要忘记在你的AndroidManifest.xml中添加以下权限来访问互联网。
< uses-permission android: name = " android.permission。互联网" / >
我自己也试过,还没有遇到任何问题。
适用于任何容器中的imageView,比如listview grid view, normal layout
private class LoadImagefromUrl extends AsyncTask< Object, Void, Bitmap > {
ImageView ivPreview = null;
@Override
protected Bitmap doInBackground( Object... params ) {
this.ivPreview = (ImageView) params[0];
String url = (String) params[1];
System.out.println(url);
return loadBitmap( url );
}
@Override
protected void onPostExecute( Bitmap result ) {
super.onPostExecute( result );
ivPreview.setImageBitmap( result );
}
}
public Bitmap loadBitmap( String url ) {
URL newurl = null;
Bitmap bitmap = null;
try {
newurl = new URL( url );
bitmap = BitmapFactory.decodeStream( newurl.openConnection( ).getInputStream( ) );
} catch ( MalformedURLException e ) {
e.printStackTrace( );
} catch ( IOException e ) {
e.printStackTrace( );
}
return bitmap;
}
/** Usage **/
new LoadImagefromUrl( ).execute( imageView, url );
嗨,我有最简单的代码试试这个
public class ImageFromUrlExample extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView imgView =(ImageView)findViewById(R.id.ImageView01);
Drawable drawable = LoadImageFromWebOperations("http://www.androidpeople.com/wp-content/uploads/2010/03/android.png");
imgView.setImageDrawable(drawable);
}
private Drawable LoadImageFromWebOperations(String url)
{
try{
InputStream is = (InputStream) new URL(url).getContent();
Drawable d = Drawable.createFromStream(is, "src name");
return d;
}catch (Exception e) {
System.out.println("Exc="+e);
return null;
}
}
}
main。xml
<LinearLayout
android:id="@+id/LinearLayout01"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:id="@+id/ImageView01"
android:layout_height="wrap_content"
android:layout_width="wrap_content"/>
试试这个
带有异常处理和异步任务的版本:
AsyncTask<URL, Void, Boolean> asyncTask = new AsyncTask<URL, Void, Boolean>() {
public Bitmap mIcon_val;
public IOException error;
@Override
protected Boolean doInBackground(URL... params) {
try {
mIcon_val = BitmapFactory.decodeStream(params[0].openConnection().getInputStream());
} catch (IOException e) {
this.error = e;
return false;
}
return true;
}
@Override
protected void onPostExecute(Boolean success) {
super.onPostExecute(success);
if (success) {
image.setImageBitmap(mIcon_val);
} else {
image.setImageBitmap(defaultImage);
}
}
};
try {
URL url = new URL(url);
asyncTask.execute(url);
} catch (MalformedURLException e) {
e.printStackTrace();
}
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