Question

我创建了一个跟踪课程信息的应用程序。目前，唯一可以动态更改的字段是modcode，目前，其余所有字段均已硬编码为输入数字1。

这是插入代码：

public boolean insertData(String ModCode,String ModDesc,int UniID,int FacID,int EduID,int NoOfTest,int NoOfAss,int NoOfPrac,int NoOfExam)
{
    SQLiteDatabase db = this.getWritableDatabase();
    ContentValues contentValues = new ContentValues();
    contentValues.put(Col_2,ModCode);
    contentValues.put(Col_3,ModDesc);
    contentValues.put(Col_4,UniID);
    contentValues.put(Col_5,FacID);
    contentValues.put(Col_6,EduID);
    contentValues.put(Col_7,NoOfTest);
    contentValues.put(Col_8,NoOfAss);
    contentValues.put(Col_9,NoOfPrac);
    contentValues.put(Col_10,NoOfExam);
    long result = db.insert(Table_Name, null, contentValues);
    if(result==-1)
        return false;
    else
        return true;

}

和插入的前端侧：

db = new DatabaseHelper(this);
textModCode = (EditText)findViewById(R.id.textModCode);
button_add = (Button)findViewById(R.id.button_add);
AddData();

按钮按下：

public void AddData(){
    button_add.setOnClickListener(
            new View.OnClickListener(){
                @Override
                public void onClick(View v){
                   boolean isInserted = db.insertData(textModCode.getText().toString(),"1",1,1,1,1,1,1,1);
                   if(isInserted=true)
                       Toast.makeText(MainActivity.this,"Data in",Toast.LENGTH_LONG).show();
                   else
                       Toast.makeText(MainActivity.this,"Sorry",Toast.LENGTH_LONG).show();
                   refresh();
                }
            }
    );
}

刷新：

public void refresh()
{
    Cursor res = db.getAllData();
    moduleList = new ArrayList<>();
    if (res != null ) {
        if  (res.moveToFirst()) {
            do {
                Module m = new Module(res.getInt(res.getColumnIndex("ModID")),res.getInt(res.getColumnIndex("NoOfTest")),res.getInt(res.getColumnIndex("NoOfAss")),res.getInt(res.getColumnIndex("NoOfPrac")),res.getInt(res.getColumnIndex("NoOfExam")),res.getString(res.getColumnIndex("ModCode")),res.getString(res.getColumnIndex("ModDesc")),res.getString(res.getColumnIndex("UniID")),res.getString(res.getColumnIndex("FacID")),res.getString(res.getColumnIndex("EduID")));
                moduleList.add(m);
            }while (res.moveToNext());
        }
    }
    /*
     */
    recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    moduleAdapter = new ModuleAdapter(this, moduleList);
    recyclerView.setAdapter(moduleAdapter);
}

“回收者”视图最初显示的是正确的所有内容，但是在滚动之后，随着每次向上或向下滚动，数字都会开始变化。

首次打开时第一次上下滚动上下滚动第二个

我做错了什么还是怎么回事？谢谢您或任何帮助

ModuleAdapter类代码

public class ModuleAdapter extends RecyclerView.Adapter<ModuleAdapter.ModuleViewHolder>{


private Context mCtx;
private List<Module> moduleList;

public ModuleAdapter(Context mCtx, List<Module> moduleList) {
    this.mCtx = mCtx;
    this.moduleList = moduleList;
}

@NonNull
@Override
public ModuleViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    LayoutInflater inflater = LayoutInflater.from(mCtx);

    View view = inflater.from(parent.getContext())
            .inflate(R.layout.module_list, parent, false);
    return new ModuleViewHolder(view);
}

@Override
public void onBindViewHolder(@NonNull ModuleViewHolder holder, int position) {
    Module module = moduleList.get(position);
    holder.textModCodeView.setText(module.getModcode());
    holder.textModuleDescView.setText(module.getModdesc());
    holder.textEducatorView.setText(holder.textEducatorView.getText()+ module.getEducator());
    holder.textNoOfTestView.setText(holder.textNoOfTestView.getText()+ String.valueOf(module.getNooftest()));
    holder.textNoOfAssView.setText(holder.textNoOfAssView.getText()+ String.valueOf(module.getNoofass()));
    holder.textNoOfPracView.setText(holder.textNoOfPracView.getText()+ String.valueOf(module.getNoofprac()));
    holder.textNoOfExamView.setText(holder.textNoOfExamView.getText()+ String.valueOf(module.getNoofexam()));

    Random r = new Random();
    int red=r.nextInt(255 - 0 + 1)+0;
    int green=r.nextInt(255 - 0 + 1)+0;
    int blue=r.nextInt(255 - 0 + 1)+0;

    GradientDrawable draw = new GradientDrawable();
    draw.setShape(GradientDrawable.RECTANGLE);
    draw.setColor(Color.rgb(red,green,blue));
    holder.textModCodeView.setBackground(draw);
}

@Override
public int getItemCount() {
    return moduleList.size();
}

class ModuleViewHolder extends RecyclerView.ViewHolder{

    TextView textModCodeView,textModuleDescView,textEducatorView,textNoOfTestView,textNoOfAssView,textNoOfPracView,textNoOfExamView;
    public ModuleViewHolder(View itemView) {
        super(itemView);

        textModCodeView = itemView.findViewById(R.id.textModCodeView);
        textModuleDescView = itemView.findViewById(R.id.textModuleDescView);
        textEducatorView = itemView.findViewById(R.id.textEducatorView);
        textNoOfTestView = itemView.findViewById(R.id.textNoOfTestView);
        textNoOfAssView = itemView.findViewById(R.id.textNoOfAssView);
        textNoOfPracView = itemView.findViewById(R.id.textNoOfPracView);
        textNoOfExamView = itemView.findViewById(R.id.textNoOfExamView);
    }
}

}

Answer 1

按照此步骤

1。在添加所有值moduleList.clear();

之前清除您的arraylist

刷新：

public void refresh()
{
    moduleList.clear();   // add this line
    Cursor res = db.getAllData();
    moduleList = new ArrayList<>();
    if (res != null ) {
        if  (res.moveToFirst()) {
            do {
                Module m = new Module(res.getInt(res.getColumnIndex("ModID")),res.getInt(res.getColumnIndex("NoOfTest")),res.getInt(res.getColumnIndex("NoOfAss")),res.getInt(res.getColumnIndex("NoOfPrac")),res.getInt(res.getColumnIndex("NoOfExam")),res.getString(res.getColumnIndex("ModCode")),res.getString(res.getColumnIndex("ModDesc")),res.getString(res.getColumnIndex("UniID")),res.getString(res.getColumnIndex("FacID")),res.getString(res.getColumnIndex("EduID")));
                moduleList.add(m);
            }while (res.moveToNext());
        }
    }
    /*
     */
    recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    moduleAdapter = new ModuleAdapter(this, moduleList);
    recyclerView.setAdapter(moduleAdapter);
}

2。更改下面的代码，如我在下面提到的（我认为视图被限制）

 holder.textEducatorView.setText("Educatore"+ module.getEducator());
    holder.textNoOfTestView.setText("NoOfTestView"+ String.valueOf(module.getNooftest()));
    holder.textNoOfAssView.setText("NoOfAssView"+ String.valueOf(module.getNoofass()));
    holder.textNoOfPracView.setText("NoOfPracView"+ String.valueOf(module.getNoofprac()));
    holder.textNoOfExamView.setText("textNoOfExamView"+ String.valueOf(module.getNoofexam()));

滚动将值添加到文本视图

1 个答案: