好久没有写东西了。备份下知识吧。免得忘记了 。
首先贴一段代码 －－ 这个是先生成一个本地的路径，将图片保存到这个文件中，然后扫描下sd卡。让系统相册重新加载下 。缺点就是只能保存到DCIM的文
件夹下边，暂时不知道怎么获取系统相机的路径，网上找了下说了好几个方法。其中有一条就是去读取本地的图片，然后根据一定的规则识别出本地相册的路径
保存下，不过觉得性能不是很好。谁有更好的方法可以提供下。
private class DownloadTask extends AsyncTask<String, Integer, String> {
private Context context;
private String filepath;
public int fileLength = 0;
public DownloadTask(Context context) {
this.context = context;
File cacheDir = new File(ImageLoader.getExternalCacheDir(context).getAbsolutePath() );
if(!cacheDir.exists()) {
cacheDir.mkdirs();
}
// filepath = ImageLoader.getExternalCacheDir(context).getAbsolutePath() + File.separator + "caihongjiayuan.jpg";
filepath = UIUtils.generateDownloadPhotoPath();
}
@SuppressWarnings("resource")
@Override
protected String doInBackground(String... sUrl) {
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, getClass()
.getName());
wl.acquire();
InputStream input = null;
OutputStream output = null;
HttpURLConnection connection = null;
try {
URL url = new URL(sUrl[0]);
connection = (HttpURLConnection) url.openConnection();
connection.setConnectTimeout(5000);
connection.setReadTimeout(20000);
connection.connect();
// expect HTTP 200 OK, so we don‘t mistakenly save error report
// instead of the file
if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
return "Server returned HTTP " + connection.getResponseCode() + " "
+ connection.getResponseMessage();
fileLength = connection.getContentLength();
input = connection.getInputStream();
output = new FileOutputStream(filepath);
byte data[] = new byte[4096];
long total = 0;
int count;
while ((count = input.read(data)) != -1) {
// allow canceling with back button
if (isCancelled())
return null;
total += count;
if (fileLength > 0) // only if total length is known
publishProgress((int)total);
output.write(data, 0, count);
}
} catch (Exception e) {
return null;
} finally {
try {
if (output != null)
output.close();
if (input != null)
input.close();
} catch (IOException ignored) {
}
if (connection != null)
connection.disconnect();
wl.release();
}
return filepath;
}
@Override
protected void onProgressUpdate(Integer... values) {
// TODO Auto-generated method stub
super.onProgressUpdate(values);
float progress = (float)values[0]/(float)fileLength;
mProgressInfo.setText(getString(R.string.download_progress_info,StringUtils.getKBUnitString(values[0]),StringUtils.getKBUnitString(fileLength)));
mProgressBar.setProgress((int)(progress * 100));
}
@Override
protected void onPostExecute(String result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
mDownloadView.setVisibility(View.GONE);
if (!TextUtils.isEmpty(result)) {
ImageUtils.scanFile(mCurrentActivity, filepath);
ToastUtils.showLongToast(mCurrentActivity, mCurrentActivity.getString(R.string.tips_img_save_path, filepath));
}else {
ToastUtils.showLongToast(mCurrentActivity, R.string.tips_download_photo_faile);
}
//
// Bitmap bitmap = BitmapFactory.decodeFile(filepath);
// boolean flag = ImageUtils.insertImageToAllbum(bitmap, mCurrentActivity);
// if (flag) {
//// ToastUtils.showLongToast(mCurrentActivity, R.string.tips_download_photo_success);
// }else {
// ToastUtils.showLongToast(mCurrentActivity, R.string.tips_download_photo_faile);
// }
}
}
参考了下别的文章，找到下边一个方法能解决大部分机型适配的问题，且可以将照片保存到系统相机拍完照的目录下。供大家参考。
private class DownloadTask extends AsyncTask<String, Integer, Boolean> { private Context context; public int fileLength = 0; private Bitmap bmp; public DownloadTask(Context context) { this.context = context; File cacheDir = new File(ImageLoader.getExternalCacheDir(context).getAbsolutePath() ); if(!cacheDir.exists()) { cacheDir.mkdirs(); } } @SuppressWarnings("resource") @Override protected Boolean doInBackground(String... sUrl) { PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE); PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, getClass() .getName()); wl.acquire(); InputStream input = null; ByteArrayOutputStream output = null; HttpURLConnection connection = null; try { URL url = new URL(sUrl[0]); connection = (HttpURLConnection) url.openConnection(); connection.setConnectTimeout(5000); connection.setReadTimeout(20000); connection.connect(); // expect HTTP 200 OK, so we don‘t mistakenly save error report // instead of the file if (connection.getResponseCode() != HttpURLConnection.HTTP_OK) return false; fileLength = connection.getContentLength(); input = connection.getInputStream(); output = new ByteArrayOutputStream(); byte data[] = new byte[4096]; long total = 0; int count; while ((count = input.read(data)) != -1) { // allow canceling with back button if (isCancelled()) return false; total += count; if (fileLength > 0) // only if total length is known publishProgress((int)total); output.write(data, 0, count); } bmp = BitmapFactory.decodeByteArray(output.toByteArray(),0 , output.toByteArray().length); return true; } catch (Exception e) { return false; } finally { try { if (output != null) output.close(); if (input != null) input.close(); } catch (IOException ignored) { } if (connection != null) connection.disconnect(); wl.release(); } } @Override protected void onProgressUpdate(Integer... values) { // TODO Auto-generated method stub super.onProgressUpdate(values); float progress = (float)values[0]/(float)fileLength; mProgressInfo.setText(getString(R.string.download_progress_info,StringUtils.getKBUnitString(values[0]),StringUtils.getKBUnitString(fileLength))); mProgressBar.setProgress((int)(progress * 100)); } @Override protected void onPostExecute(Boolean result) { // TODO Auto-generated method stub super.onPostExecute(result); mDownloadView.setVisibility(View.GONE); if (result.booleanValue() && ImageUtils.insertImageToAllbum(bmp, mCurrentActivity)) { }else { ToastUtils.showLongToast(mCurrentActivity, R.string.tips_download_photo_faile); } } }
两个方法的区别就是将FileOutputStream换成了ByteArrayOutputStream项目中主要是有显示下载进度条的需求，所以稍微复杂了点。
另外： ImageUtils 中insertImage 方法如下。
public static boolean insertImageToAllbum(Bitmap bitmap,Context mContext) {
if (bitmap != null) {
String uri = MediaStore.Images.Media.insertImage(mContext.getContentResolver(),bitmap, "", "");
if (!TextUtils.isEmpty(uri)) {
String filePath = getRealPathFromURI(Uri.parse(uri),mContext);
ToastUtils.showLongToast(mContext, mContext.getString(R.string.tips_img_save_path, filePath));
scanFile(mContext,filePath);
return true;
}
}
return false;
}
public static void scanFile(Context mContext,String path){
MediaScannerConnection.scanFile(mContext, new String[] { path }, null,
new MediaScannerConnection.OnScanCompletedListener() {
public void onScanCompleted(String path, Uri uri) {
}
});
}
方法scanFile是让系统重新加载SD卡的 。。
over，有疑问请留言，欢迎指正错误。