java - 如何修复我的 onSaveInstanceState 和 onRestoreInstanceState？

Question

我试图在屏幕旋转期间保存用户的所有值和点击，但我的按钮点击和文本视图不起作用。我花了很多时间试图弄清楚在这个方法中写什么，但都没有奏效。来自 Select your Tip 按钮的输入和 textView 输出目前未保存。

@Override
    protected void onSaveInstanceState(@NonNull Bundle outState) {
        super.onSaveInstanceState(outState);
        Log.d(TAG, "onSaveInstanceState: Started");
        String text = txtNumOfSplits.getText().toString();
        int no = Integer.parseInt(text);
        outState.putInt("count", no);

        String num_of_splits = txtNumOfSplits.getText().toString();

        //Convert String to Integer
        int no2 = Integer.parseInt(num_of_splits);
        outState.putInt("count", no2);

        money = Double.parseDouble(edtBillAmount.getText().toString());
        outState.putString("bill", String.valueOf(money));

    }

    @Override
    protected void onRestoreInstanceState(@NonNull Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        Log.d(TAG, "onRestoreInstanceState: Started");

        String text = txtNumOfSplits.getText().toString();
        int no = savedInstanceState.getInt("count");
        txtNumOfSplits.setText(no + "");


        money = Double.parseDouble(edtBillAmount.getText().toString());
        String money = savedInstanceState.getString("bill");
        txtTotalBill.setText("Total Bill\n$" + finalAmount.toString());

    }

    btn_add = findViewById(R.id.btn_add);
    btn_subtract = findViewById(R.id.btn_subtract);
    btn_20 = findViewById(R.id.btn_20);
    btn_15 = findViewById(R.id.btn_15);
    btn_10 =findViewById(R.id.btn_10);
    btn_calculate = findViewById(R.id.btn_calculate);
    btn_reset = findViewById(R.id.btn_reset);

    txtBill = findViewById(R.id.txtBill);
    txtTip = findViewById(R.id.txtTip);
    txtSplit = findViewById(R.id.txtSplit);
    txtRoundUp = findViewById(R.id.txtRoundUp);
    txtNumOfSplits = findViewById(R.id.txtNumOfSplits);
    txtTotalHeading = findViewById(R.id.txtTotalHeading);
    txtTotalPerPerson = findViewById(R.id.txtTotalPerPerson);
    txtTotalBill = findViewById(R.id.txtTotalBill);
    txtTotalTip = findViewById(R.id.txtTotalTip);
    txt_switch_error = findViewById(R.id.txt_switch_error);

    switchRoundUp = (Switch) findViewById(R.id.switchRoundUp);
    switchRoundDown = (Switch) findViewById(R.id.switchRoundDown);

    edtBillAmount = findViewById(R.id.edtBillAmount);

    horizontalLine = findViewById(R.id.horizontalLine);

Answer 1

那是你需要的吗？如有必要，您可以添加双值解析。

    private static final String NUM_OF_SPLITS_KEY = "num_of_splits_key";
    private static final String SELECTED_BUTTON_KEY = "selected_button_key";
    private static final String TOTAL_PER_PERSON_KEY = "total_per_person_key";
    private static final String TOTAL_BILL_KEY = "total_bill_key";
    private static final String TOTAL_TIP_KEY = "total_tip_key";

    @Override
    protected void onSaveInstanceState(@NonNull Bundle outState) {
        super.onSaveInstanceState(outState);
        Log.d(TAG, "onSaveInstanceState: Started");

        String textNumOfSplits = txtNumOfSplits.getText().toString();
        int numOfSplits = Integer.parseInt(textNumOfSplits);
        outState.putInt(NUM_OF_SPLITS_KEY, numOfSplits);

        int selectedButtonId = 0;

        if (btn_10.isSelected()) selectedButtonId = R.id.btn_10;
        else if (btn_15.isSelected()) selectedButtonId = R.id.btn_15;
        else if (btn_20.isSelected()) selectedButtonId = R.id.btn_20;

        outState.putInt(SELECTED_BUTTON_KEY, selectedButtonId);

        outState.putString(TOTAL_PER_PERSON_KEY, txtTotalPerPerson.getText().toString());
        outState.putString(TOTAL_BILL_KEY, txtTotalBill.getText().toString());
        outState.putString(TOTAL_TIP_KEY, txtTotalTip.getText().toString());

    }

    @Override
    protected void onRestoreInstanceState(@NonNull Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        Log.d(TAG, "onRestoreInstanceState: Started");

        int numOfSplits = savedInstanceState.getInt(NUM_OF_SPLITS_KEY);
        txtNumOfSplits.setText(numOfSplits + "");

        String selectedButtonId = savedInstanceState.getInt(SELECTED_BUTTON_KEY);

        if (selectedButtonId == btn_10.getId()) selectButton(btn_10);
        else if (selectedButtonId == btn_15.getId()) selectButton(btn_15);
        else if (selectedButtonId == btn_20.getId()) selectButton(btn_20);

        String totalPerPerson = savedInstanceState.getString(TOTAL_PER_PERSON_KEY);
        txtTotalPerPerson.setText(totalPerPerson);

        String totalBill = savedInstanceState.getString(TOTAL_BILL_KEY);
        txtTotalBill.setText(totalBill);

        String totalTip = savedInstanceState.getString(TOTAL_TIP_KEY);
        txtTotalTip.setText(totalTip);
    }

    private void selectButton(@NonNull Button button) {
        button.setSelected(true);
    }