Question

我想在recyclerview中显示数组中的图像，所以我将数组传递给适配器，但是recyclerview不会绑定到适配器，因为我在“ onBindViewHolder”中使用了“ Log.d” 但是Log没有显示消息。我的代码有什么问题？还有其他解决方案吗？

片段中：

 @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_plan, container, false);

    paths[0] = "/storage/emulated/0/demonuts_upload_gallery/1543839716755.jpg";
    paths[1] = "/storage/emulated/0/demonuts_upload_gallery/1543839716755.jpg";
    paths[2] = "/storage/emulated/0/demonuts_upload_gallery/1543839716755.jpg";
    paths[3] = "/storage/emulated/0/demonuts_upload_gallery/1543839716755.jpg";
    paths[4] = "/storage/emulated/0/demonuts_upload_gallery/1543839716755.jpg";

    adapter = new ImagesBodyAdapter(view.getContext());
    LinearLayoutManager layoutManager = new LinearLayoutManager(view.getContext(),LinearLayoutManager.HORIZONTAL, false);
    recyclerView = view.findViewById(R.id.recycler);
    recyclerView.setLayoutManager(layoutManager);
    adapter.addItems(paths);
    adapter.notifyDataSetChanged();
    recyclerView.setAdapter(adapter);

适配器类为：

public class ImagesBodyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

private String[] PATHS = new String[5];

private Context context;

public ImagesBodyAdapter(Context context){
    this.context = context;
}
@NonNull
@Override
public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    LayoutInflater inflater = LayoutInflater.from(context);
    View view = inflater.inflate(R.layout.image_body_item,viewGroup,false);
    return new ViewHolderItemDetail(view);
}

@Override
public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, int i) {
    //ViewHolderItemDetail holder = (ViewHolderItemDetail) viewHolder;

    Log.d("adapter","recycler binded!");

    for (int counter=0; counter<PATHS.length; counter++)
    {
        File imageFile = new  File(PATHS[i]);
        if(imageFile.exists()) {
            ((ViewHolderItemDetail) viewHolder).imageBody.setImageBitmap(BitmapFactory.decodeFile(imageFile.getAbsolutePath()));
        }
    }

}

public void addItems(String[] paths){
    for (int i=0; i<paths.length;i++){
        this.PATHS[i] = paths[i];
        notifyItemChanged(i);
       // notifyDataSetChanged();
    }
}
private class ViewHolderItemDetail extends RecyclerView.ViewHolder{
    ImageView imageBody;

    ViewHolderItemDetail(View v) {
        super(v);
        imageBody = v.findViewById(R.id.imageBody);
    }
 }

谢谢

Answer 1

使用此库：Picasso Library

并参考此链接以将图像加载到ImageView中（在您的适配器BindViewHolder中）。这简单： Picasso Use Case

编辑样例代码

Picasso.get().load("your/url/or/file/path").into(imageView);

编辑2：您一定不能在adapter内迭代。该适配器负责一个ViewHolder，仅负责将要加载的一幅图像。

Answer 2

Stavro Xhardha建议使用一个库将图像加载到ImageView中（尽管我个人偏爱Glide https://github.com/bumptech/glide）

但是，您的问题之一是没有调用onBindViewHolder。我可能会误会，但是在设置适配器上的数据之前，我总是会先在RecylerView上设置适配器。所以代替；

# -*- coding: utf-8 -*
import serial
import math
import time
import RPi.GPIO as GPIO





servoPIN = 18
GPIO.setmode(GPIO.BCM)
GPIO.setup(servoPIN, GPIO.OUT)


fire_gun = GPIO.PWM(servoPIN, 50)   #GPIO 5 for PWM with 50Hz
fire_gun.start(2.5) #Initialization



"""
def gunRight():
    #fire_gun = GPIO.PWM(servoPIN, 50)  #GPIO 5 for PWM with 50Hz
    #fire_gun.start(2.5)    #Initialization

    print "Shot Fire The First Net Gun"
    fire_gun.ChangeDutyCycle(4.9)
    time.sleep(0.4)
    fire_gun.ChangeDutyCycle(7.2)
    time.sleep(0.4)
    print "Servo Motor Back To Rest Position"
    fire_gun.stop()
"""




ser = serial.Serial("/dev/ttyUSB0", 115200)

def getTFminiData():
    while True:
        count = ser.in_waiting
        if count > 8:
            recv = ser.read(9)
            ser.reset_input_buffer()
            if recv[0] == 'Y' and recv[1] == 'Y': # 0x59 is 'Y'
                low = int(recv[2].encode('hex'), 16)
                high = int(recv[3].encode('hex'), 16)
                distance = low + high * 256
                #My unit conversion starts here
                dist = float(distance) /100 
                print(distance)
                print "Distance to object is:",dist,"Meters"
                #GPIO.setup(TRIG, GPIO.OUT)
                #GPIO.setup(ECHO, GPIO.IN)

                #if dist <= 0.70:
                    #GPIO.output(5, True)   





try:
    if ser.is_open == False:
       ser.open()
       for i in range(500):
           getTFminiData()
           if dist <= 0.70:
          fire_gun.ChangeDutyCycle(4.9)
              time.sleep(0.4)
              GPIO.cleanup()


except KeyboardInterrupt:   # Ctrl+C
    if ser != None:
        #GPIO.cleanup()
    ser.close()

您将拥有；

recyclerView = view.findViewById(R.id.recycler);
recyclerView.setLayoutManager(layoutManager);
adapter.addItems(paths);
adapter.notifyDataSetChanged();
recyclerView.setAdapter(adapter);

Answer 3

您可以使用滑行库或piccaso库前往https://github.com/bumptech/glide滑行访问https://github.com/square/picasso以获得piccaso库因此，现在您只需轻松制作适配器即可。

首先，您应该在类中为图像设置一个参数；例如，您创建了一个Person Class；

所以你的课程是：

public class Person{
String name ; 
String lastName;
String imgUrl;
//define setter, getter and constactive

}

在bindview的适配器中，您只需在毕加索中设置此图像，例如下面的代码

    public void onBindViewHolder(final ViewHolder holder,final int position){
  Piccaso.with(contect).load(list.get(position).getImageUrl()).into(holder.imageview);
}

Answer 4

在片段中，您可以将上下文作为 getActivity（），因此尝试将代码更改为：

adapter = new ImagesBodyAdapter(view.getContext());

至

adapter = new ImagesBodyAdapter(getActivity());

如何在recyclerview中显示图像？

4 个答案: