protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_image);
imageView = (ImageView) findViewById(R.id.imageView);
Intent intent = getIntent();
Uri imageUri = intent.getData();
// Picasso.with(this).load(imageUri).into(imageView);
if(imageUri == null){
Log.d(TAG, "Check");
}
//BitmapFactory.Options options = new BitmapFactory.Options();
// options.inSampleSize = 8;
// bm = MediaStore.Images.Media.getBitmap(getContentResolver(),imageUri);
Bitmap bm = null;
try{
InputStream image;
try{
image = getContentResolver().openInputStream(imageUri);
bm = BitmapFactory.decodeStream(image);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
catch (Exception e){
e.printStackTrace();
}
//BitmapFactory.Options options = new BitmapFactory.Options();
// bm = BitmapFactory.decodeFile(file.getAbsolutePath(),options);
if ((bm == null)) {
prints("It doesn't work");
}
//Log.d(TAG,"Going to convert image.");
imageView.setImageBitmap(bm);
我已经查看了一堆StackOverFlow问题，我已经尝试了所有问题，正如您在评论代码中看到的那样。我试图在拍摄照片时获得一个未更改的位图。位图的像素位置对我的目标至关重要。图像质量很高，可能是更大的文件。我的位图始终为空，我确保我的Uri不是。有任何想法吗？
答案 0 :(得分：2)
我认为以下代码可以帮助您
private void setImage(String path, CircleImageView img) {
options = new DisplayImageOptions.Builder()
.cacheInMemory(true)
.cacheOnDisk(true)
.considerExifParams(true)
.bitmapConfig(Bitmap.Config.RGB_565)
.showImageOnLoading(R.drawable.user)
.showImageForEmptyUri(R.drawable.user)
.showImageOnFail(R.drawable.user)
.build();
ImageLoader.getInstance().displayImage(path, img, options, new SimpleImageLoadingListener() {
@Override
public void onLoadingStarted(String imageUri, View view) {
super.onLoadingStarted(imageUri, view);
}
@Override
public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
super.onLoadingFailed(imageUri, view, failReason);
}
@Override
public void onLoadingCancelled(String imageUri, View view) {
super.onLoadingCancelled(imageUri, view);
}
@Override
public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
super.onLoadingComplete(imageUri, view, loadedImage);
}
}, new ImageLoadingProgressListener() {
@Override
public void onProgressUpdate(String s, View view, int i, int i1) {
}
});
}
为SimpleImageLoadingListener()
答案 1 :(得分：0)
该文件的分辨率太大，无法制作位图。没有足够的内存来构造位图，因此返回null。
尝试使用非常小的图像文件查看。
答案 2 :(得分：0)
如果来自您的移动存储设备，您可以直接从URI获取Bitmap。
public Bitmap getBitmapFromURI(Uri uri){
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = getActivity().getContentResolver().query(uri, filePathColumn, null, null, null);
if(cursor!=null){
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
File f_image = new File(cursor.getString(columnIndex));
cursor.close();
BitmapFactory.Options o2 = new BitmapFactory.Options();
return BitmapFactory.decodeFile(f_image.getAbsolutePath(), o2);
}
return null;
}
如果文件太大而无法加载..您需要压缩图像并显示。为此，您还需要使用异步任务。
我制作了一个Image压缩器任务，你可以将它用于大图像
public class ConvertBase64Task extends AsyncTask<Void, Bitmap, Bitmap> {
private ByteArrayOutputStream baos = new ByteArrayOutputStream();
private File file;
private int CompressionRatio = 80; //You can change it by what ever ratio you want. in 0 to 100.
private boolean shouldrotate = true;
private ImageCompressiorListner imageCompressiorListner;
public ConvertBase64Task(File file) {
this.file = file;
}
public void setRotation(boolean isRotate) {
shouldrotate = isRotate;
}
public void setCompressionRatio(int Ratio) {
CompressionRatio = Ratio;
}
public void setImageCompressiorListner(ImageCompressiorListner imageCompressiorListner) {
this.imageCompressiorListner = imageCompressiorListner;
}
@Override
protected void onPreExecute(){
}
@Override
protected Bitmap doInBackground(Void... params) {
try {
//***** Fatching file
//*****Code for Orientation
Matrix matrix = new Matrix();
if (shouldrotate) {
ExifInterface exif1 = new ExifInterface(file.getAbsolutePath());
int orientation = exif1.getAttributeInt(
ExifInterface.TAG_ORIENTATION, 1);
Log.d("EXIF", "Exif: " + orientation);
if (orientation == 6) {
matrix.postRotate(90);
} else if (orientation == 3) {
matrix.postRotate(180);
} else if (orientation == 8) {
matrix.postRotate(270);
} else {
matrix.postRotate(0);
}
} else {
matrix.postRotate(0);
}
try {
BitmapFactory.Options option = new BitmapFactory.Options();
option.inJustDecodeBounds = true;
BitmapFactory.decodeFile(file.getAbsolutePath(), option);
int file_size = Integer.parseInt(String.valueOf(file.length() / 1024));
Log.e("ImageSize", "" + file_size);
int scale = 1;
if (file_size < 512) {
Log.e("image size is good", "image size is less");
} else if (file_size < 1024) {
Log.e("image size is 1 mb", "image size is heavy");
scale = 2;
} else if (file_size < 1536) {
Log.e("image size is 1.5 mb", "image size is heavy");
scale = 2;
} else if (file_size < 2048) {
Log.e("image size is 2 mb", "image size is heavy");
scale = 4;
} else {
Log.e("image size > 2 mb", "image size is heavy");
scale = 4;
}
Log.e("Scale", "Finaly Scaling with " + scale);
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
Bitmap pickimg = BitmapFactory.decodeFile(file.getAbsolutePath(), o2);
if (pickimg.getWidth() > 1280 || pickimg.getHeight() > 1000) {
int width = pickimg.getWidth();
int height = pickimg.getHeight();
while (width > 1280 || height > 700) {
width = (width * 90) / 100;
height = (height * 90) / 100;
}
pickimg = Bitmap.createScaledBitmap(pickimg, width, height, true);
} else {
pickimg = Bitmap.createBitmap(pickimg, 0, 0, pickimg.getWidth(), pickimg.getHeight(), matrix, true); // rotating bitmap
}
pickimg.compress(Bitmap.CompressFormat.JPEG, CompressionRatio, baos);
return pickimg;
} catch (OutOfMemoryError e) {
e.printStackTrace();
return null;
} catch (Exception e) {
e.printStackTrace();
return null;
}
} catch (Throwable e) {
e.printStackTrace();
return null;
}
}
@Override
protected void onPostExecute(Bitmap result) {
super.onPostExecute(result);
if (result != null) {
if(imageCompressiorListner!=null){
imageCompressiorListner.onImageCompressed(result);
}
} else {
if(imageCompressiorListner!=null){
imageCompressiorListner.onError();
}
}
}
public interface ImageCompressiorListner {
void onImageCompressed(Bitmap bitmap);
void onError();
}
}
您可以使用以下
ConvertBase64Task task = new ConvertBase64Task(File Object of Image);
task.setImageCompressiorListner(new ConvertBase64Task.ImageCompressiorListner() {
@Override
public void onImageCompressed(Bitmap bitmap) {
}
@Override
public void onError() {
}
});
task.execute();
希望这会帮助你。