Question

我在MainActivity中有这个方法，我想在片段上的按钮中使用它们，但我不知道如何将片段中import sys from time import sleep words = "#Project_Blitz_v1.5" for char in words: sleep(0.03) sys.stdout.write(char) sys.stdout.flush() sleep (0.5) fb = "..." for char in fb: sleep(0.03) sys.stdout.write(char) sys.stdout.flush() words = "eyyyyy" for char in words: sleep(0.03) sys.stdout.write(char) sys.stdout.flush()的数据发送到活动并使用按钮。

EditText

我在片段类中有这个，但我不知道如何传递EditTexts值。

public void alta(View v) {
        AdminSQLiteOpenHelper admin = new AdminSQLiteOpenHelper(this);
        SQLiteDatabase bd = admin.getWritableDatabase();
        String nome = et1.getText().toString();
        String edad = et2.getText().toString();
        String geno = et3.getText().toString();
        String curp = et4.getText().toString();
        ContentValues registro = new ContentValues();
        registro.put("nombre", nome);
        registro.put("edad", edad);
        registro.put("genero", geno);
        registro.put("curp", curp);
        bd.insert("usuarios", null, registro);
        bd.close();
        et1.setText("");
        et2.setText("");
        et3.setText("");
        et4.setText("");
        Toast.makeText(this, "Se cargaron los datos",
                Toast.LENGTH_SHORT).show();
    }

    public void modificacion(View v) {
        AdminSQLiteOpenHelper admin = new AdminSQLiteOpenHelper(this);
        SQLiteDatabase bd = admin.getWritableDatabase();
        String nome = et1.getText().toString();
        String edad = et2.getText().toString();
        String geno = et3.getText().toString();
        String curp = et4.getText().toString();
        ContentValues registro = new ContentValues();
        registro.put("nombre", nome);
        registro.put("edad", edad);
        registro.put("genero", geno);
        registro.put("curp", curp);
        int cant = bd.update("usuarios", registro, "curp=" + curp, null);
        bd.close();
        if (cant == 1)
            Toast.makeText(this, "se modificaron los datos", Toast.LENGTH_SHORT)
                    .show();
        else
            Toast.makeText(this, "no existe un usuario con ese nombre",
                    Toast.LENGTH_SHORT).show();
    }

Answer 1

首先，重要的是Activity不会尝试直接访问片段内部的视图（这最初会起作用，但在边缘情况下会因无效引用而导致崩溃）。我建议的是在MainActivity中创建一个接口，Fragment将通知Activity。

public class MainActivity {
     String textArr[4] = new String[4];
     public void setEditTextValue(String text, int id) {
         textArr[id] = text;
     }
}

public class Fragment1 extends Fragment {

   public void updateData() {
       MainActivity main = (MainActivity)getActivity();
       main.setEditTextValue(iet1.getText().toString(), 0);
       main.setEditTextValue(iet2.getText().toString(), 1);
       main.setEditTextValue(iet3.getText().toString(), 2);
       main.setEditTextValue(iet4.getText().toString(), 3);
       main.modificacion(); // Which doesn't need view and can just use the data saved in the array
   }
}

如何从EditText中获取从片段到活动的价值？

1 个答案: