更新了更多代码
我正在尝试抓取刚拍摄的照片并以编程方式将其设置为ImageView。
按下图片按钮，
picture_button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
takePhoto(mTextureView);
}
});
它运行takePhoto方法：
public void takePhoto(View view) {
try {
mImageFile = createImageFile();
final ImageView latest_picture = (ImageView) findViewById(R.id.latest_picture);
final RelativeLayout latest_picture_container = (RelativeLayout) findViewById(R.id.latest_picture_container);
final String mImageFileLocationNew = mImageFileLocation.replaceFirst("^/", "");
Toast.makeText(getApplicationContext(), "" + mImageFile, Toast.LENGTH_SHORT).show();
Uri uri = Uri.fromFile(mImageFile);
Toast.makeText(getApplicationContext(), ""+uri, Toast.LENGTH_LONG).show();
latest_picture.setImageURI(uri);
latest_picture_container.setVisibility(View.VISIBLE);
} catch (IOException e){
e.printStackTrace();
}
lockFocus();
captureStillImage();
}
运行createImageFile()和captureStillImage()
private void captureStillImage() {
try {
CaptureRequest.Builder captureStillBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureStillBuilder.addTarget(mImageReader.getSurface());
int rotation = getWindowManager().getDefaultDisplay().getRotation();
captureStillBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation));
CameraCaptureSession.CaptureCallback captureCallback = new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, TotalCaptureResult result) {
super.onCaptureCompleted(session, request, result);
//Toast.makeText(getApplicationContext(), "Image Taken", Toast.LENGTH_SHORT).show();
unLockFocus();
}
};
mCameraCaptureSession.capture(captureStillBuilder.build(), captureCallback, null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
File createImageFile() throws IOException {
String timestamp = new SimpleDateFormat("yyyyMMdd").format(new Date());
String subFolder = "";
if(pref_session_unique_gallery.equals("yes")){
if(event_name != null){
subFolder = event_name;
} else {
subFolder = timestamp;
}
} else {
subFolder = "_GEN";
}
if(event_name == null){
event_name = "";
} else {
event_name = event_name + "_";
}
String imageFileName = "CPB_"+event_name+timestamp+"_";
File storageDirectory = new File(Environment.getExternalStorageDirectory() + File.separator + "CPB" + File.separator + subFolder);
storageDirectory.mkdir();
File image = File.createTempFile(imageFileName, ".jpg", storageDirectory);
mImageFileLocation = image.getAbsolutePath();
return image;
}
并且图像保存在此处：
private static class ImageSaver implements Runnable {
private final Image mImage;
private ImageSaver(Image image) {
mImage = image;
}
@Override
public void run() {
ByteBuffer byteBuffer = mImage.getPlanes()[0].getBuffer();
byte[] bytes = new byte[byteBuffer.remaining()];
byteBuffer.get(bytes);
FileOutputStream fileOutputStream = null;
try {
fileOutputStream = new FileOutputStream(mImageFile);
fileOutputStream.write(bytes);
} catch (IOException e) {
e.printStackTrace();
} finally {
mImage.close();
if(fileOutputStream != null){
try {
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
我在createImageFile()之后获得了正确的图像路径，并将其烘烤以显示每次都是什么。但即使setVisibility上的latest_picture_container工作正常......如果我评论InputStream，Bitmap和setImageBitmap，那么latest_picture_container显示正常。不知道为什么这是错误的。
由于某种原因，URI在文件后面带有三个斜杠，
file:///storage/0/...
答案 0 :(得分：3)
AssetManager#open()方法仅适用于您应用的资源;即项目的/assets文件夹中的文件。由于您尝试打开外部文件，因此应该在从路径创建的FileInputStream对象上使用File。此外，takePhoto()方法是在将任何内容写入文件之前在ImageView上设置图像，这将导致空ImageView。
由于您的应用程序直接使用相机，我们可以从写入图像文件的相同字节数组中解码图像，并为自己节省不必要的存储读取。此外，在您的代码示例中，文件写入发生在单独的线程上，因此我们也可以在执行图像解码时利用它，因为它将最小化对UI线程的影响。
首先，我们将创建一个界面，ImageSaver可以通过该界面将图片传回Activity以显示在ImageView中。
public interface OnImageDecodedListener {
public void onImageDecoded(Bitmap b);
}
然后我们需要稍微更改ImageSaver类以在构造函数中获取Activity参数。我还添加了File参数，因此Activity的相应字段不必是static。
private static class ImageSaver implements Runnable {
private final Activity mActivity;
private final Image mImage;
private final File mImageFile;
public ImageSaver(Activity activity, Image image, File imageFile) {
mActivity = activity;
mImage = image;
mImageFile = imageFile;
}
@Override
public void run() {
ByteBuffer byteBuffer = mImage.getPlanes()[0].getBuffer();
byte[] bytes = new byte[byteBuffer.remaining()];
byteBuffer.get(bytes);
final Bitmap b = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
mActivity.runOnUiThread(new Runnable() {
@Override
public void run() {
((OnImageDecodedListener) mActivity).onImageDecoded(b);
}
}
);
FileOutputStream fileOutputStream = null;
...
}
}
只要我们在字节数组中获取图像数据，我们就会对其进行解码并将其传递回Activity，因此它不必等待文件写入，这可以在文件中安静地进行。背景。我们需要在UI线程上调用接口方法，因为我们在那里“触摸”View。
Activity需要实现界面，我们可以将View相关内容从takePhoto()移动到onImageDecoded()方法。
public class MainActivity extends Activity
implements ImageSaver.OnImageDecodedListener {
...
@Override
public void onImageDecoded(Bitmap b) {
final ImageView latest_picture =
(ImageView) findViewById(R.id.latest_picture);
final RelativeLayout latest_picture_container =
(RelativeLayout) findViewById(R.id.latest_picture_container);
latest_picture.setImageBitmap(b);
latest_picture_container.setVisibility(View.VISIBLE);
}
public void takePhoto(View view) {
try {
mImageFile = createImageFile();
captureStillImage();
lockFocus();
}
catch (IOException e) {
e.printStackTrace();
}
}
...
}
最后，我们需要在ImageSaver的{{1}}方法中实际执行ImageReader。再次按照这个例子，它就是这样的。
onImageAvailable()答案 1 :(得分：0)
我通常使用Picasso库
将依赖项添加到build.gradle
compile 'com.squareup.picasso:picasso:2.5.2'
由于您要获取文件路径，请将路径设置为File对象，然后让Picasso从手机中获取图像，并将其设置为所需的ImageView
File fileLocation = new File(uri) //file path, which can be String, or Uri
Picasso.with(this).load(fileLocation).into(imageView);
我建议您将Picasso用于应用中的任何类型的图像活动，无论是在线还是离线。毕加索是由Square制作的，在图像加载，缓存方面是最好的......
答案 2 :(得分：0)
public static String getEDirectory(String folderName,Activity activity) {
if(Environment.MEDIA_MOUNTED.equalsIgnoreCase(Environment.getExternalStorageState())){
LogUtils.e( activity.getExternalFilesDir(folderName).getAbsolutePath());
return activity.getExternalFilesDir(folderName).getAbsolutePath();
}else{
return activity.getFilesDir().getAbsolutePath() +File.separator+folderName;
}
}
public static Uri getImageUri(String shortname,Activity activity) {
if (shortname == null) {
shortname = "www.jpg";
}
String path = DataStore.getEDirectory("pure",activity);
File files = new File(path);
files.mkdirs();
File file = new File(path, shortname);
return Uri.fromFile(file);
}
public static Uri attemptStartCamera(Activity ctx){
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
String latestfilename = System.currentTimeMillis() + ".jpg";
Uri imageUri = getImageUri(latestfilename,ctx);
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
ctx.startActivityForResult(intent, MsgCodes.PICK_CAMERA);
return imageUri;
}
活动：
mUri = attemptStartCamera(Activity.this);
通过这种方式，你得到了Uri。
您可以在onActivityResult中加载图片：
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode==MsgCodes.PICK_CAMERA && resultCode == RESULT_OK){
mImageView.setImageUri(mUri);
}
}
答案 3 :(得分：0)
尝试这个简单的代码
ImageView imgView = view.findViewById(R.id.lw_foto);
imgView.setImageURI(mListaContactos.get(i).foto);