嘿，我花了很多时间来修复以下代码中出现的错误。 该错误是由于内存不足（堆）造成的。 直到现在我没有找到任何解决方案（这是我第三天正在寻找它，真的很累:(） 有人请告诉我一个很好的解决方案。
activity_preview.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/setimage"
tools:context=".Preview" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:layout_above="@+id/ad"
android:layout_alignParentTop="true">
<ImageView
android:id="@+id/imageView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="fitXY" />
<ProgressBar
android:id="@+id/pbDownload"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_alignLeft="@+id/image"
android:layout_alignRight="@+id/image"
android:layout_below="@+id/textView1"
android:layout_marginTop="15dp" />
<Button
android:id="@+id/save"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/pbDownload"
android:text="Button"
android:visibility="gone" />
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="4.91"
android:visibility="invisible" />
</LinearLayout>
<com.google.ads.AdView
android:id="@+id/ad"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
ads:adUnitId="a152e9gh407f4ae69"
ads:loadAdOnCreate="true"
ads:adSize="BANNER"
android:layout_above="@+id/llbuttons"
android:layout_marginBottom="5dp"
/>
<LinearLayout
android:layout_width="match_parent"
android:id="@+id/llbuttons"
android:layout_height="70dp"
android:layout_alignLeft="@+id/scrollView1"
android:layout_alignParentBottom="true"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:weightSum="1" >
<Button
android:id="@+id/imageButton2"
android:layout_width="0dp"
android:layout_height="60dp"
android:background="@drawable/custom_setwall"
android:onClick="onclick_setwall"
android:scaleType="fitXY"
android:layout_weight="0.5"
android:layout_marginRight="5dp"/>
<Button
android:id="@+id/imageView5"
android:layout_width="0dp"
android:layout_height="60dp"
android:layout_marginRight="5dp"
android:layout_weight="0.25"
android:background="@drawable/custom_save"
android:onClick="onclick_save"
android:scaleType="fitXY" />
<Button
android:id="@+id/imageButton6"
android:layout_width="0dp"
android:layout_height="60dp"
android:background="@drawable/custom_share"
android:onClick="onclick_share"
android:scaleType="fitXY"
android:layout_weight="0.25"
/>
</LinearLayout>
</RelativeLayout>
Preview.java
package com.hb.nfswallpapers;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Random;
import com.google.ads.AdRequest;
import com.google.ads.AdView;
import com.hitbytes.nfswallpapers.ImageDownloader;
import com.hitbytes.nfswallpapers.ImageDownloader.ImageLoaderListener;
import android.media.MediaScannerConnection;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.WallpaperManager;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.support.v4.app.NotificationCompat;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.ImageView.ScaleType;
public class Preview extends Activity {
private ProgressBar pb;
private Button bnxt,bprv,bhome,save,bsave,photos;
private ImageView img;
private static Bitmap bmp;
private TextView percent;
private FileOutputStream fos;
private ImageDownloader mDownloader;
String imagesources;
int pindex,i;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_preview);
initViews();
Bundle extras = getIntent().getExtras();
imagesources = extras.getString("photourl");
/*--- instantiate our downloader passing it required components ---*/
mDownloader = new ImageDownloader(imagesources, pb, save, img, percent, Preview.this, bmp, new ImageLoaderListener() {
@Override
public void onImageDownloaded(Bitmap bmp) {
Preview.bmp = bmp;
/*--- here we assign the value of bmp field in our Loader class
* to the bmp field of the current class ---*/
}
});
/*--- we need to call execute() since nothing will happen otherwise ---*/
mDownloader.execute();
}
private void initViews() {
save = (Button) findViewById(R.id.save);
photos= (Button) findViewById(R.id.imageButton4);
bsave= (Button) findViewById(R.id.imageButton5);
//bnxt=(Button) findViewById(R.id.bnext);
//bprv=(Button) findViewById(R.id.bprev);
/*--- we are using 'this' because our class implements the OnClickListener ---*/
img = (ImageView) findViewById(R.id.imageView1);
img.setScaleType(ScaleType.FIT_XY);
pb = (ProgressBar) findViewById(R.id.pbDownload);
pb.setVisibility(View.INVISIBLE);
percent = (TextView) findViewById(R.id.textView1);
percent.setVisibility(View.INVISIBLE);
}
public void onclick_save(View v)
{
saveImageToSD();
}
public void onclick_share(View v)
{
Intent sharingIntent = new Intent(android.content.Intent.ACTION_SEND);
sharingIntent.setType("text/plain");
String shareBody = "Find more wallpapers & images https://play.google.com/store/apps/details?id=com.hitbytes.nfswallpapers";
sharingIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, imagesources+"\n\n");
sharingIntent.putExtra(android.content.Intent.EXTRA_TEXT, shareBody);
startActivity(Intent.createChooser(sharingIntent, "Share via"));
}
public void onclick_setwall(View v)
{
Random r = new Random();
int rand =r.nextInt(1750-1000) + 1000;
String ran=String.valueOf(rand);
String pin=String.valueOf(pindex);
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
/*--- you can select your preferred CompressFormat and quality.
* I'm going to use JPEG and 100% quality ---*/
bmp.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
// get the height and width of screen
int height = metrics.heightPixels;
int width = metrics.widthPixels;
WallpaperManager wallpaperManager = WallpaperManager.getInstance(this);
try {
wallpaperManager.setBitmap(bmp);
wallpaperManager.suggestDesiredDimensions(width, height);
Toast.makeText(this, "Wallpaper Set", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
e.printStackTrace();
}
}
private void saveImageToSD() {
/*--- this method will save your downloaded image to SD card ---*/
Random r = new Random();
int rand =r.nextInt(1750-1000) + 1000;
String ran=String.valueOf(rand);
String pin=String.valueOf(pindex);
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
/*--- you can select your preferred CompressFormat and quality.
* I'm going to use JPEG and 100% quality ---*/
bmp.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
/*--- create a new file on SD card ---*/
File direct = new File(Environment.getExternalStorageDirectory() + "/NFS Wallpapers");
if (!direct.exists()) {
File wallpaperDirectory = new File("/sdcard/NFS Wallpapers/");
wallpaperDirectory.mkdirs();
}
File file = new File(new File("/sdcard/NFS Wallpapers/"), ran+pin+"Image.jpg");
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
/*--- create a new FileOutputStream and write bytes to file ---*/
try {
fos = new FileOutputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
try {
fos.write(bytes.toByteArray());
fos.close();
MediaScannerConnection.scanFile(this,
new String[] { file.toString() }, null,null);
Toast.makeText(this, "Image saved", Toast.LENGTH_SHORT).show();
NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(
this).setAutoCancel(true)
.setContentTitle("Download complete..!")
.setSmallIcon(R.drawable.ic_launcher)
.setContentText("Image successfully downloaded!");
NotificationCompat.BigPictureStyle bigPicStyle = new NotificationCompat.BigPictureStyle();
bigPicStyle.bigPicture(bmp);
bigPicStyle.setBigContentTitle("Download complete");
mBuilder.setStyle(bigPicStyle);
Intent intent1 = new Intent(Intent.ACTION_VIEW);
intent1.setDataAndType(Uri.fromFile(file), "image/jpeg");
PendingIntent resultPendingIntent = PendingIntent.getActivity(this, 0, intent1, PendingIntent.FLAG_UPDATE_CURRENT);
mBuilder.setContentIntent(resultPendingIntent);
NotificationManager mNotificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
// mId allows you to update the notification later on.
mNotificationManager.notify(100, mBuilder.build());
} catch (IOException e) {
e.printStackTrace();
}
}
}
ImageDownloader.java
package com.hitbytes.nfswallpapers;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.SystemClock;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
public class ImageDownloader extends AsyncTask<Void, Integer, Void> {
ProgressBar pb;
String url;
Button save;
Context c;
int progress;
ImageView img;
Bitmap bmp;
TextView percent;
ImageLoaderListener listener;
/*--- constructor ---*/
public ImageDownloader(String url, ProgressBar pb, Button save,
ImageView img, TextView percent, Context c, Bitmap bmp, ImageLoaderListener listener) {
/*--- we need to pass some objects we are going to work with ---*/
this.url = url;
this.pb = pb;
this.save = save;
this.c = c;
this.img = img;
img.setVisibility(View.VISIBLE);
this.percent = percent;
this.bmp = bmp;
this.listener = listener;
}
/*--- we need this interface for keeping the reference to our Bitmap from the MainActivity.
* Otherwise, bmp would be null in our MainActivity*/
public interface ImageLoaderListener {
void onImageDownloaded(Bitmap bmp);
}
@Override
protected void onPreExecute() {
progress = 0;
pb.setVisibility(View.VISIBLE);
percent.setVisibility(View.VISIBLE);
//Toast.makeText(c, "Loading images", Toast.LENGTH_SHORT).show();
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... arg0) {
bmp = getBitmapFromURL(url);
while (progress!=0) {
progress += 100;
publishProgress(progress);
/*--- an image download usually happens very fast so you would not notice
* how the ProgressBar jumps from 0 to 100 percent. You can use the method below
* to visually "slow down" the download and see the progress bein updated ---*/
}
save.setEnabled(true);
return null;
}
@Override
protected void onProgressUpdate(Integer... values) {
/*--- show download progress on main UI thread---*/
pb.setProgress(values[0]);
percent.setText("");
super.onProgressUpdate(values);
}
@Override
protected void onPostExecute(Void result) {
if (listener != null) {
listener.onImageDownloaded(bmp);
}
//Bitmap b = Bitmap.createScaledBitmap(bmp, 200, 200, false);
img.setImageBitmap(bmp);
save.setEnabled(true);
//Toast.makeText(c, "Download complete", Toast.LENGTH_SHORT).show();
super.onPostExecute(result);
}
public static Bitmap getBitmapFromURL(String link) {
/*--- this method downloads an Image from the given URL,
* then decodes and returns a Bitmap object
---*/
try {
URL url = new URL(link);
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
} catch (IOException e) {
e.printStackTrace();
Log.e("getBmpFromUrl error: ", e.getMessage().toString());
return null;
}
}
}
答案 0 :(得分：1)
请看一下这个链接：http://developer.android.com/training/displaying-bitmaps/load-bitmap.html它可能对您有帮助。
您可以尝试使用inJustDecodeBounds并在解码之前获取图像尺寸。喜欢：
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
InputStream input = connection.getInputStream();
BitmapFactory.decodeStream(input ,null,options);
然后设置最大宽度和高度并对其进行解码。上面有一个示例代码，您可以找到两种方法来执行此操作。
答案 1 :(得分：0)
此错误可以通过代码清理来解决，例如删除全局变量，堆上的字符串对象等。请查看是否可以将全局变量转换为局部变量。
ProgressBar pb;
String url;
Button save;
Context c;
int progress;
ImageView img;
Bitmap bmp;
TextView percent;
ImageLoaderListener listener;