如何解决此字符串和整数问题?

Question

你看我有一个问题：是否有可能在不完全更改代码的情况下以某种方式将该路径更改为int？

我正在使用安卓工作室，目前正在开发应用程序，但我正在努力解决一件事。

我有一个图像的字符串路径，它需要是 int 才能工作。

String path1 = Environment.getDataDirectory().getAbsolutePath() + "/data/sk.lotario.bg/app_imgBuns/0.png";
String path2 = Environment.getDataDirectory().getAbsolutePath() + "/data/sk.lotario.bg/app_imgBuns/1.png";

List<SliderBN> sliderBNS = new ArrayList<>();
for(int i = 0; i < Recipe.bnPos; i++){
sliderBNS.add(new SliderBN(path1));
sliderBNS.add(new SliderBN(path2));

在课堂上 滑块BN 我有这个：

public class SliderBN {
private int image;
SliderBN(int image){
this.image = image;
}
public int getImage() {
return image;
}

问题是我不想在这里将其更改为字符串，因为我将不得不更改很多代码。

这是该类的适配器：

private List<SliderBN> sliderBNS;
private ViewPager2 vpBN;
private static final String TAG = "SliderBNAdapter";
public static int vpBNPosition = 0;
public SliderBNAdapter(List<SliderBN> sliderBNS, ViewPager2 vpBN) {
this.sliderBNS = sliderBNS;
this.vpBN = vpBN;
}
public SliderBNAdapter() {
}
@NonNull
@Override
public SliderViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
return new SliderViewHolder(
LayoutInflater.from(parent.getContext()).inflate(
R.layout.slider_item_container,
parent,
false
)
);
}
@Override
public void onBindViewHolder(@NonNull SliderViewHolder holder, int position) {
holder.setImage(sliderBNS.get(position));
if (position == sliderBNS.size()) {
vpBN.post(runnable);
}
}

@Override
public int getItemCount() {
vpBNPosition = vpBN.getCurrentItem();
Log.i(TAG,"position "+vpBNPosition);
return sliderBNS.size();
}
class SliderViewHolder extends RecyclerView.ViewHolder {
private ImageView imageView;
SliderViewHolder(@NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.imageSlide);
}
void setImage(SliderBN sliderBN){
imageView.setImageResource(sliderBun.getImage());
}
}
private Runnable runnable = new Runnable() {
@Override
public void run() {
sliderBNS.addAll(sliderBNS);
notifyDataSetChanged();
}
};

Answer 1

您可以向 SliderBN 添加两个属性。一个是String path，另一个是int index.创建SliderBN时，只需设置所需的值。然后在代码中，您可以使用所需的属性。

public class SliderBN {
private int index;
private String path;
SliderBN(String path, int index){
this.index = index;
this.path = path;
}
public int getIndex() {
return index;
}
public String getPath() {
return path;
}
}

在创建映像开始时，您可以执行以下操作：

String pathToImages = Environment.getDataDirectory().getAbsolutePath() + "/data/sk.lotario.bg/app_imgBuns/";
List<SliderBN> sliderBNS = new ArrayList<>();
// Here you need to be sure that you always have the images else you will 
// receive exceptions! If this images will be dynamically added/removed then 
// you need another way for retrieving the names and loading them in the list.
for(int i = 0; i < Recipe.bnPos; i++){
sliderBNS.add(new SliderBN(pathToImages + i + ".png", i));
}

例如，在需要设置图像路径的地方，您可以调用getPath方法：

class SliderViewHolder extends RecyclerView.ViewHolder {
private ImageView imageView;
SliderViewHolder(@NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.imageSlide);
}
void setImage(SliderBN sliderBN){
// Here you can set the path to the image
// I saw that you setImageResource(int resId)
// But for this to work you need the Image ids
// In the current case we can use setImageURI(Uri uri)
// With Uri you need to provide the path to the image not the id
File imgFile = new File(sliderBun.getPath());
if(imgFile.exists())
{
Uri uri = Uri.fromFile(imgFile);
imageView.setImageURI(uri);
}
else
{
// Log here message that the file does not exist
// and also log the path so you can see what is going wrong
}
}
}

注意：由于您的代码现在，您不需要index (int) in class SliderBN因为您在开头添加所有图像的列表中有此信息。我仍然不知道你所有的用例，为什么我离开了它。请参阅使用列表索引获取该位置上的对象的示例：

@Override
public void onBindViewHolder(@NonNull SliderViewHolder holder, int position) 
{
// Here we get SliderBN object from the list by list position and not by 
// internal properties
holder.setImage(sliderBNS.get(position));
if (position == sliderBNS.size()) {
vpBN.post(runnable);
}
}

您需要索引的一个地方是，如果您有包含未排序SliderBN对象的 List，并且您可以轻松地对它们进行排序。然后，可以使用此属性index对该列表中的对象进行排序。但是在您的情况下，您从for loop内部的增长索引创建图像，因此您的列表实际上是排序的。

祝大家好运！