android - 检索从 sqlite 数据库加载的微调器中选定元素的 id

Question

我要检索的 ID 应与 sqlite 数据库中的相同，而不是微调器项目行的 ID。

我使用了以下链接中的代码并得到了一些异常。

load from spinner sqlite with text and value

我认为问题出在这里:

anId = Integer.valueOf(( (AnSco) spnAnsco.getSelectedItem () ).getIdan());

我尝试过:

anId = ( (AnSco) spnAnsco.getSelectedItem () ).getIdan();

总是同样的问题。

加载微调器

private void loadSpinnerAnsco() {
        List<String> ansco = new ArrayList<String>();
        db = new DatabaseHelper(this);
        boolean ok = true;
        try {
            SQLiteDatabase dbs = db.getWritableDatabase();

            cursor = dbs.rawQuery(
                    "Select idan as _id, ansco from TAnSco order by ansco",
                    null);

            // looping through all rows and adding to list
            if (cursor.moveToFirst()) {
                do {
                    ansco.add(cursor.getString(1));
                } while (cursor.moveToNext());
            }

            // closing connection
            cursor.close();
            dbs.close();

            ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
                    android.R.layout.simple_spinner_item, ansco);

            // Drop down layout style - list view with radio button
            dataAdapter
                    .setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

            // attaching data adapter to spinner
            spnAnsco.setAdapter(dataAdapter);

        } catch (Exception ex) {
            ok = false;
            AlertDialog.Builder b = new AlertDialog.Builder(this);
            b.setMessage(ex.toString());
            b.show();
        } finally {
            if (ok) {
                db.close();
            }
        }

    }

获取选中的项目

public class anscoSpinner implements OnItemSelectedListener {

        @Override
        public void onItemSelected(AdapterView<?> parent, View view,
                int position, long id) {
            String label = parent.getItemAtPosition(position).toString();
            AnSco an=new AnSco(label);
            anId = Integer.valueOf(( (AnSco) spnAnsco.getSelectedItem () ).getIdan());
            loadSpinnerPeriode(anId);
            // Showing selected spinner item
            Toast.makeText(parent.getContext(), "You selected: " + label+ " AnId: "+anId,
                    Toast.LENGTH_LONG).show();
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {
            // TODO Auto-generated method stub

        }
        // TODO Auto-generated method stub

    }

项目等级 Ansco

public class AnSco {

    int idan;
    String ansco;

    public AnSco(int idan, String ansco) {
        this.idan = idan;
        this.ansco = ansco;
    }

    public AnSco(String ansco) {
        this.ansco = ansco;
    }

    public AnSco() {
        // TODO Auto-generated constructor stub
    }

    public int getIdan() {
        return idan;
    }
    public void setIdan(int idan) {
        this.idan = idan;
    }

    public String getAnsco() {
        return ansco;
    }
    public void setAnsco(String ansco) {
        this.ansco = ansco;
    }

}

堆栈跟踪:

10-21 13:34:59.319: E/AndroidRuntime(438): FATAL EXCEPTION: main
10-21 13:34:59.319: E/AndroidRuntime(438): java.lang.ClassCastException: java.lang.String
10-21 13:34:59.319: E/AndroidRuntime(438):  at com.android.moyenne.activity.MoyenneMain$anscoSpinner.onItemSelected(MoyenneMain.java:306)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.widget.AdapterView.fireOnSelected(AdapterView.java:864)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.widget.AdapterView.access$200(AdapterView.java:42)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.widget.AdapterView$SelectionNotifier.run(AdapterView.java:830)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.os.Handler.handleCallback(Handler.java:587)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.os.Handler.dispatchMessage(Handler.java:92)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.os.Looper.loop(Looper.java:123)
10-21 13:34:59.319: E/AndroidRuntime(438):  at android.app.ActivityThread.main(ActivityThread.java:4627)
10-21 13:34:59.319: E/AndroidRuntime(438):  at java.lang.reflect.Method.invokeNative(Native Method)
10-21 13:34:59.319: E/AndroidRuntime(438):  at java.lang.reflect.Method.invoke(Method.java:521)
10-21 13:34:59.319: E/AndroidRuntime(438):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-21 13:34:59.319: E/AndroidRuntime(438):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-21 13:34:59.319: E/AndroidRuntime(438):  at dalvik.system.NativeStart.main(Native Method)
10-21 13:35:02.119: I/Process(438): Sending signal. PID: 438 SIG: 9

Answer 1

I used this tutorial load from spinner sqlite with text and value and get some exceptions during running.

我使用了您提供的链接中的解决方案。我建议进行以下更改。

在您的数据库类中创建以下方法

public List < Ansco> getAllLabels(){
    List < Ansco > lansco = new ArrayList < Ansco > ();
    // Select All Query
    String selectQuery = "SELECT  * FROM "  TAnSco;// tAnsco is your table name?

    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);

    // looping through all rows and adding to list
    if ( cursor.moveToFirst () ) {
        do {
            lansco.add ( new Ansco ( cursor.getString(0) , cursor.getString(1) ) );
        } while (cursor.moveToNext());
    }

    // closing connection
    cursor.close();
    db.close();

    // returning labels
    return lansco;
}

然后在你的 load spinner 方法中

 List <Ansco> ansco = db.getAllLabels();
 ArrayAdapter<Ansco> dataAdapter = new ArrayAdapter<Ansco>(this,
                android.R.layout.simple_spinner_item, ansco);
 dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
 spnAnsco.setAdapter(dataAdapter);

然后在您的微调器选择中

  int databaseId = Integer.parseInt ( ( (SpinnerObject) spin2.getSelectedItem () ).getId () );

并更改您的 Ansco 类

public class AnSco {

    String idan; // change to string
    String ansco;

    public AnSco(String idan, String ansco) {
        this.idan = idan;
        this.ansco = ansco;
    }

    public AnSco(String ansco) {
        this.ansco = ansco;
    }

    public AnSco() {
        // TODO Auto-generated constructor stub
    }

    public String getIdan() {
        return idan;
    }
    public void setIdan(String idan) {
        this.idan = idan;
    }

    public String getAnsco() {
        return ansco;
    }
    public void setAnsco(String ansco) {
        this.ansco = ansco;
    }

}