在我的应用程序中，有一个“上传图片”的按钮：从相机拍摄照片或从图库中选择。
在这两个选项中，有3个问题：
1）再次点击上传另一张图片时 - 应用程序会崩溃
2）在第一次“上传”时，图片在侧面旋转（逆时针旋转90度）
3）图片的大小是原始大小，我希望它被压缩到125x125的分辨率。
请帮助（即使你有一个问题的解决方案）
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.app.Fragment;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.OutputStream;
import entities.Order;
public class SellABookFragment extends Fragment implements View.OnClickListener {
private ImageView ivBookPicture;
private EditText etBookName, etBookAuthor, etBookGenre, etBookPublishing, etQuantity, etBookPrice, etBookDetails;
private Button bUploadPicture, bAddBook;
public SellABookFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_sell_a_book, container, false);
ivBookPicture = (ImageView) view.findViewById(R.id.ivBook_Picture);
etBookName = (EditText) view.findViewById(R.id.etBook_Name);
etBookAuthor = (EditText) view.findViewById(R.id.etAuthor_Name);
etBookGenre = (EditText) view.findViewById(R.id.etGenre);
etBookPublishing = (EditText) view.findViewById(R.id.etPublishing_Year);
etQuantity = (EditText) view.findViewById(R.id.etBook_Quantity);
etBookPrice = (EditText) view.findViewById(R.id.etBook_Price);
etBookDetails = (EditText) view.findViewById(R.id.etBook_Details);
bUploadPicture = (Button) view.findViewById(R.id.bUpload_Picture);
bAddBook = (Button) view.findViewById(R.id.bAdd_Book);
bUploadPicture.setOnClickListener(this);
bAddBook.setOnClickListener(this);
return view;
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.bUpload_Picture:
selectPicture();
break;
case R.id.bAdd_Book:
addBook();
break;
}
}
private void addBook() {
try {
HomeActivity.backEnd.addOrder(new Order(HomeActivity.LoggedUser.getID(),
etBookGenre.getText().toString(),
etBookName.getText().toString(),
Integer.parseInt(etBookPublishing.getText().toString()),
etBookAuthor.getText().toString(),
Double.parseDouble(etBookPrice.getText().toString()),
(Integer) ivBookPicture.getTag()));
} catch (Exception e) {
Toast.makeText(getActivity().getApplicationContext(), e.getMessage(), Toast.LENGTH_LONG).show();
}
}
private void selectPicture() {
final CharSequence[] options = {
getResources().getString(R.string.take_photo),
getResources().getString(R.string.gallery_choose),
getResources().getString(R.string.cancel)};
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setTitle(getResources().getString(R.string.upload_picture));
builder.setItems(options, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int item) {
if (options[item].equals(getResources().getString(R.string.take_photo))) {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File f = new File(android.os.Environment.getExternalStorageDirectory(), "tmp.jpg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
startActivityForResult(intent, 1);
} else if (options[item].equals(getResources().getString(R.string.gallery_choose))) {
Intent intent = new Intent(Intent.ACTION_PICK,
MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(intent, 2);
} else
dialog.dismiss();
}
});
builder.show();
}
Bitmap bitmap;
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
OutputStream outFile;
String path = android.os.Environment.getExternalStorageDirectory()
+ File.separator
+ "MyApp";
File file;
if (resultCode == Activity.RESULT_OK) {
if (bitmap != null) {
ivBookPicture.setImageBitmap(null);
bitmap.recycle();
bitmap = null;
}
try {
if (requestCode == 1) {
File f = new File(Environment.getExternalStorageDirectory().toString());
for (File tmp : f.listFiles()) {
if (tmp.getName().equals("tmp.jpg")) {
f = tmp;
break;
}
}
BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
bitmap = BitmapFactory.decodeFile(f.getAbsolutePath(), bitmapOptions);
ivBookPicture.setImageBitmap(bitmap);
if (f.delete()) {
file = new File(path, String.valueOf(System.currentTimeMillis()) + ".jpg");
try {
outFile = new FileOutputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
} else if (requestCode == 2) {
Uri selectedImage = data.getData();
String[] filePath = {MediaStore.Images.Media.DATA};
Cursor c = getActivity().getContentResolver().query(selectedImage, filePath, null, null, null);
c.moveToFirst();
int columnIndex = c.getColumnIndex(filePath[0]);
String picturePath = c.getString(columnIndex);
c.close();
bitmap = (BitmapFactory.decodeFile(picturePath));
Log.w("image path", picturePath);
ivBookPicture.setImageBitmap(bitmap);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
包含上传图片的ImageView：
<ImageView
android:id="@+id/ivBook_Picture"
android:layout_width="@dimen/sell_a_book_picture_size"
android:layout_height="@dimen/sell_a_book_picture_size"
android:src="@mipmap/ic_launcher" />
谢谢！
答案 0 :(得分：1)
public Bitmap compressBySize(String pathName, int targetWidth,
int targetHeight) {
BitmapFactory.Options opts = new BitmapFactory.Options();
opts.inJustDecodeBounds = true;
Bitmap bitmap = BitmapFactory.decodeFile(pathName, opts);
int imgWidth = opts.outWidth;
int imgHeight = opts.outHeight;
int widthRatio = (int) Math.ceil(imgWidth / (float) targetWidth);
int heightRatio = (int) Math.ceil(imgHeight / (float) targetHeight);
if (widthRatio > 1 || heightRatio > 1) {
if (widthRatio > heightRatio) {
opts.inSampleSize = widthRatio;
} else {
opts.inSampleSize = heightRatio;
}
}
opts.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeFile(pathName, opts);
return bitmap;
}
使用此方法进行压缩，只需自己设置 targetWidth＆amp; targetHeight 。
此外，您可以使用bitmap.compress(Bitmap.CompressFormat.JPEG, compressRate, byteOutputStream);按质量压缩位图。
对于崩溃，这是因为图片位图占用了太多内存。您应该压缩图片并记住在首次上传后释放内存。您可以考虑使用 WeakReference 。