如何通过共享首选项android将图像从Activity B传递到上一个Activity A

Question

如果我更改了第二个活动的图像，我想更改上一个活动的图像，当我返回上一个活动时，应该更改图像。

https://i.stack.imgur.com/7bTnj.png

Answer 1

尝试在您的代码中自定义以下代码。它会起作用的。

这是您要跟踪的第一个活动，如果图像已更改并希望加载更改的图像。

public class A extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_a);
        //YOUR OTHER CODE HERE..

        startActivityForResult(new Intent(A.this, B.class), 111);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == 111 && resultCode == RESULT_OK) {
            if (data.getExtras() != null) {
                //set your image path which has been returned by previous activity to your imageview here
                //data.getExtras().getString("image_path")
            }
        }
        super.onActivityResult(requestCode, resultCode, data);
    }
}

这是您要更改图像的下一个活动

public class B extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_b);
        //YOUR OTHER CODE HERE..
    }

    @Override
    public void onBackPressed() {
        Intent intent = new Intent();
        intent.putExtra("image_path", "CHANGED_IMAGE_PATH");
        setResult(RESULT_OK, intent);
        super.onBackPressed();
    }
}