Question

为什么我无法从SQLite中检索数据？我错过了什么吗？我已经阅读了很多文档并试图解决它，但仍然失败。

WorkDetailsTable.java

  Button btn1=(Button)findViewById(R.id.button2);
        btn1.setOnClickListener(new View.OnClickListener() {
        public void onClick(View arg0) {
        AlertDialog.Builder builder=new AlertDialog.Builder(WorkDetailsTable.this);
        builder.setTitle("Data Saved");
        builder.setMessage("Are you sure you want to save?");
        builder.setIcon(android.R.drawable.ic_dialog_alert);
        builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int ii) {
            long ab = ts.insertTimeSheet(name, weather, date, status);
            Toast.makeText(context, "Data Saved", Toast.LENGTH_SHORT).show();
            Intent intent=new Intent(WorkDetailsTable.this,DisplayData.class);
            intent.putExtra("name",name); //name will be used in another class
            startActivity(intent);

DisplayDate.java

public class DisplayData extends AppCompatActivity {
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.displaydata);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
        final String name1 = getIntent().getExtras().getString("name");
        Toast.makeText(getApplicationContext(),name1, Toast.LENGTH_SHORT).show();

        if(name1.equals("John"))
        {
            SQLiteDatabase db=(new MyDatabaseHelper(this)).getReadableDatabase();
            Cursor cursor=db.rawQuery("SELECT Weather,Date,Status FROM Information WHERE Name = ?",new String[]{""+name1});
            if(cursor.getCount()==1)
            {
                String weather=cursor.getString(cursor.getColumnIndex("Weather"));
                String date=cursor.getString(cursor.getColumnIndex("Date"));
                String status=cursor.getString(cursor.getColumnIndex("Status"));


            }
            db.close();

        }

displaydata.xml

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

        <HorizontalScrollView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="15dp" >

            <TableLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:stretchColumns="|"
                android:layout_marginBottom="25dp">


                <TableRow
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:id="@+id/tableRow1">

                    <TextView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:id="@+id/textView10"
                        android:background="@drawable/cell_shape"
                        android:textSize="17sp"
                        android:text="weather"/>

                    <TextView android:id="@+id/textView111"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:textSize="17sp"
                        android:background="@drawable/cell_shape"
                        android:text="date"/>

       <TextView android:id="@+id/textView11"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:textSize="17sp"
                    android:background="@drawable/cell_shape"
                    android:text="status"/>
                </TableRow>
         //   <TableRow>

           //     <TextView android:id="@+id/textView1111"
             //       android:layout_width="wrap_content"
               //     android:layout_height="wrap_content"
                 //   android:textSize="17sp"
                   // android:background="@drawable/cell_shape"/>


    </TableRow>
    </TableLayout>
    </HorizontalScrollView>
    </LinearLayout>
    </ScrollView>

我也试过这个但没有运气

 TextView tvTemp=(TextView)findViewById(R.id.textView1111);
        tvTemp.setText(weather + date + status);

应检索数据并按行显示在另一个类中，而不是在editText上显示。我该怎么做才能实现这一目标？

Answer 1

点击“是”后，您将转到下一个活动并将名称传递给它：

public class DisplayData extends AppCompatActivity {
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.displaydata);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

  Bundle bundle=getIntent().getExtras();
    String name="";
      if(bundle!=null)
      {
       name=bundle.getString("name");
           }

         //check whether you get the name value here or not..(use log)


        SQLiteDatabase db=(new MyDatabaseHelper(this)).getReadableDatabase();
        Cursor cursor=db.rawQuery("SELECT Weather,Date,Status FROM Information WHERE Name = ?",new String[]{""+name1});
        if(cursor.getCount()==1)
        {
            String weather=cursor.getString(cursor.getColumnIndex("Weather"));//give the proper index of weather and same for rest.
            String date=cursor.getString(cursor.getColumnIndex("Date"));
            String status=cursor.getString(cursor.getColumnIndex("Status"));


        }
        db.close();

}

从SQLite中检索数据并在另一个类中按行显示

1 个答案: