在退出应用程序(onSaveInstanceState)后保存图像视图状态



我有一个应用程序,我允许用户从画廊中挑选图片,它用作个人资料图片,选择图片并设置在我的应用程序中的"图像视图"中。

问题是,当应用程序关闭时, ou 活动被更改 图片消失,或再次返回 de 默认图片,我想保存此图片状态,以便在返回活动或关闭并重新打开应用程序时图片继续在那里,不需要重新设置。我是开发新手,请您能帮助我查看下面的代码并进行所需的更改并给我现成的代码,我将非常感谢,因为我花了几天时间去做,但我仍然不能。我需要一个现成的代码,因为我是新手,如果你尝试解释一些我不明白的东西。

这是我选择图片的代码:

public class MainActivity extends Activity {
private static int RESULT_LOAD_IMG = 1;
String imgDecodableString;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}
public void loadImagefromGallery(View view) {
    // Create intent to Open Image applications like Gallery, Google Photos
    Intent galleryIntent = new Intent(Intent.ACTION_PICK,
            android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    // Start the Intent
    startActivityForResult(galleryIntent, RESULT_LOAD_IMG);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    try {
        // When an Image is picked
        if (requestCode == RESULT_LOAD_IMG && resultCode == RESULT_OK
                && null != data) {
            // Get the Image from data
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };
            // Get the cursor
            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            // Move to first row
            cursor.moveToFirst();
            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            imgDecodableString = cursor.getString(columnIndex);
            cursor.close();
            ImageView imgView = (ImageView) findViewById(R.id.imgView);
            // Set the Image in ImageView after decoding the String
            imgView.setImageBitmap(BitmapFactory
                    .decodeFile(imgDecodableString));
        } else {
            Toast.makeText(this, "You haven't picked Image",
                    Toast.LENGTH_LONG).show();
        }
    } catch (Exception e) {
        Toast.makeText(this, "Something went wrong", Toast.LENGTH_LONG)
                .show();
    }
}

}

尝试重写 onSaveInstanceState Activity 生命周期方法。这是一篇关于其最佳实践的博客文章。http://inthecheesefactory.com/blog/fragment-state-saving-best-practices/en

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