Question

如何在imageView中保存最后选定或捕获的图像？那么当用户关闭程序并再次返回时不需要再次设置或拍摄图像？

xml fle：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:tools="http://schemas.android.com/tools"
              android:id="@+id/LinearLayout1"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              android:orientation="vertical"
              android:padding="10dp" >
  <LinearLayout
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:gravity="center"
          android:padding="5dp" >
    <Button
            android:id="@+id/btnSelectPhoto"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Select Photo" />
  </LinearLayout>
  <LinearLayout
          android:layout_width="match_parent"
          android:layout_height="match_parent"
          android:orientation="vertical"
          android:padding="10dp" >
    <ImageView
            android:id="@+id/viewImage"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:src="@drawable/camera" />
  </LinearLayout>
</LinearLayout>

java文件：

public class MainActivity extends Activity {
    ImageView viewImage;
    Button b;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        b=(Button)findViewById(R.id.btnSelectPhoto);
        viewImage=(ImageView)findViewById(R.id.viewImage);
        b.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                selectImage();
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds options to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

      private void selectImage() {
        final CharSequence[] options = { "Take Photo", "Choose from Gallery","Cancel" };

        AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
        builder.setTitle("Add Photo!");
        builder.setItems(options, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int item) {
                if (options[item].equals("Take Photo"))
                {
                    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                    File f = new File(android.os.Environment.getExternalStorageDirectory(), "temp.jpg");
                    intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
                    startActivityForResult(intent, 1);
                }
                else if (options[item].equals("Choose from Gallery"))
                {
                    Intent intent = new   Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                    startActivityForResult(intent, 2);
                }
                else if (options[item].equals("Cancel")) {
                    dialog.dismiss();
                }
            }
        });
        builder.show();
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {  
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == RESULT_OK) {
            if (requestCode == 1) {
                File f = new File(Environment.getExternalStorageDirectory().toString());
                for (File temp : f.listFiles()) {
                    if (temp.getName().equals("temp.jpg")) {
                        f = temp;
                        break;
                    }
                }
                try {
                    Bitmap bitmap;
                    BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
                    bitmap = BitmapFactory.decodeFile(f.getAbsolutePath(),
                            bitmapOptions); 

                    viewImage.setImageBitmap(bitmap);
                    String path = android.os.Environment
                            .getExternalStorageDirectory()
                            + File.separator
                            + "Phoenix" + File.separator + "default";
                    f.delete();
                    OutputStream outFile = null;
                    File file = new File(path, String.valueOf(System.currentTimeMillis()) + ".jpg");
                    try {
                        outFile = new FileOutputStream(file);
                        bitmap.compress(Bitmap.CompressFormat.JPEG, 85, outFile);
                        outFile.flush();
                        outFile.close();
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else if (requestCode == 2) {
                Uri selectedImage = data.getData();
                String[] filePath = { MediaStore.Images.Media.DATA };
                Cursor c = getContentResolver().query(selectedImage,filePath, null, null, null);
                c.moveToFirst();
                int columnIndex = c.getColumnIndex(filePath[0]);
                String picturePath = c.getString(columnIndex);
                c.close();
                Bitmap thumbnail = (BitmapFactory.decodeFile(picturePath));
                Log.w("path of image from gallery......******************.........", picturePath+"");
                viewImage.setImageBitmap(thumbnail);
            }
        }
    }   
}

这段代码来自： http://www.c-sharpcorner.com/UploadFile/e14021/capture-image-from-camera-and-selecting-image-from-gallery-o/

非常感谢马赫

Answer 1

您可以将图像（路径）保存为OnPause（）中的首选项，然后在OnResume（）中再次加载它。使用该路径，您可以再次在ImageView中设置图像。这是它的两个步骤。

有关Android应用程序生命周期的更多信息：http://developer.android.com/training/basics/activity-lifecycle/pausing.html

在imageView中保存最后选定或捕获的图像

1 个答案: