如何将最终的List<File> keepImage = []传递到下一页

List<File> keepImage = ...; // 最终的List<File>

Intent intent = new Intent(CurrentActivity.this, NextActivity.class);
intent.putExtra("keepImageList", new ArrayList<>(keepImage));
startActivity(intent);

List<File> keepImage = getIntent().getSerializableExtra("keepImageList");

public class DataHolder {
    public static List<File> keepImage = new ArrayList<>();
}

// 在需要赋值的地方：
DataHolder.keepImage = ...; // 最终的List<File>

List<File> keepImage = DataHolder.keepImage;

public class MyApp extends Application {
    private List<File> keepImage;

    public List<File> getKeepImage() {
        return keepImage;
    }

    public void setKeepImage(List<File> keepImage) {
        this.keepImage = keepImage;
    }
}

List<File> keepImage = ...; // 最终的List<File>
MyApp myApp = (MyApp) getApplication();
myApp.setKeepImage(keepImage);

MyApp myApp = (MyApp) getApplication();
List<File> keepImage = myApp.getKeepImage();