如何使用Android上的MediaStore将数据从Camera保存到磁盘？

Question

对于我的应用程序,我一直在使用我自己的Camera类来拍摄图像和我自己的数据库但很快就无法跟上变化,我决定使用Android内置的相机应用程序来完成这项工作,但是我似乎无法得到它来保存文件.我在这里错过了什么？该应用程序似乎保存文件,但它只是0字节.我查找了Camera应用程序的源代码,并在Extras中查找"输出"以保存文件.任何帮助将不胜感激.

Public class CameraTest extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button cameraButton = (Button) findViewById(R.id.cameraButton);
        cameraButton.setOnClickListener( new OnClickListener(){
            public void onClick(View v ){
                ContentValues values = new ContentValues();
                values.put(Images.Media.TITLE, "title");
                values.put(Images.Media.BUCKET_ID, "test");
                values.put(Images.Media.DESCRIPTION, "test Image taken");
                Uri uri = getContentResolver().insert(Media.EXTERNAL_CONTENT_URI, values);
                Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
                intent.putExtra("output", uri.getPath());
                startActivityForResult(intent,0);
            }
        });

    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode== 0 && resultCode == Activity.RESULT_OK){
            ((ImageView)findViewById(R.id.pictureView)).setImageURI(data.getData());
        }
    }


}

Answer 1

这与下面的代码一起使用,因为我对最后一个代码感到有些愚蠢.我仍然认为必须有一个更好的方法,以便原始图像仍然保存在某个地方.它仍然向我发送较小的25%大小的图像.

public class CameraTest extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    Button cameraButton = (Button) findViewById(R.id.cameraButton);
    cameraButton.setOnClickListener( new OnClickListener(){
        public void onClick(View v ){

            Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");

            startActivityForResult(intent,0);
        }
    });

}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode== 0 && resultCode == Activity.RESULT_OK) {
        Bitmap x = (Bitmap) data.getExtras().get("data");
        ((ImageView)findViewById(R.id.pictureView)).setImageBitmap(x);
        ContentValues values = new ContentValues();
        values.put(Images.Media.TITLE, "title");
        values.put(Images.Media.BUCKET_ID, "test");
        values.put(Images.Media.DESCRIPTION, "test Image taken");
        values.put(Images.Media.MIME_TYPE, "image/jpeg");
        Uri uri = getContentResolver().insert(Media.EXTERNAL_CONTENT_URI, values);
        OutputStream outstream;
        try {
            outstream = getContentResolver().openOutputStream(uri);
            x.compress(Bitmap.CompressFormat.JPEG, 70, outstream);
            outstream.close();
        } catch (FileNotFoundException e) {
            //
        } catch (IOException e) {
            //
        }
    }
}

此外,我知道Android的杯形蛋糕版本应该很快修复小图像尺寸.

Answer 2

以下代码将启动默认摄像头并让摄像头将图像保存到指定的uri.关键是将额外的"MediaStore.EXTRA_OUTPUT"与所需的uri放在一起.

File file = new File(Environment.getExternalStorageDirectory().getPath() + "/Images/" + image_name + ".jpg");
Uri imageUri = Uri.fromFile(file);

Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);

startActivityForResult(intent, 0);