从SharedPreferences检索值时，无法将java.lang.String强制转换为java.lang.Integer [英] Getting java.lang.String cannot be cast to java.lang.Integer when retrieving value from SharedPreferences

问题描述

我正在尝试使用SharedPreferences存储一些值并在应用程序打开时检索它们，但是我在检索某些int值时遇到问题。

I am trying to use SharedPreferences to store some values and retrieve them when the app opens, but I have issues with retrieving some int values.

我尝试了转换将该值转换为字符串，然后使用Integer.ParseInt检索该值，但仍然出现错误。

I have tried converting the value to a string and then using Integer.ParseInt to retrieve the value, but I still get an error.

这是应该存储我的值的位置：

void putP1Index(int index) {
    SharedPreferences.Editor mEditor = mPrefs.edit();
    mEditor.putInt(keyP1Index, index);
    mEditor.apply();
}

void putP2Index(int index) {
    SharedPreferences.Editor mEditor = mPrefs.edit();
    mEditor.putInt(keyP2Index, index);
    mEditor.apply();
}

它们是从另一个类中保存的：

They are saved from a different class:

private MainGame mainGame;
private SavedValues savedValues;


ScoreSetter(MainGame mainGame) {
    this.mainGame = mainGame;
    savedValues = new SavedValues(mainGame);
}

void setScore(who) {
switch (who) {
        case 1:
            ++indexP1;
            savedValues.putP1Index(indexP1);
//Some code...
        case 2:
            ++indexP2;
            savedValues.putP2Index(indexP2);
//Some code...
}
}

我尝试这样检索它：

int getP1Index() {
    return mPrefs.getInt(keyP1Index, 0);
}

int getP2Index() {
    return mPrefs.getInt(keyP2Index, 0);
}

通过从不同的类别进行呼叫：

by calling them from a different class:

void getSavedValues() {
    indexP1 = savedValues.getP1Index();
    indexP2 = savedValues.getP2Index();
}

在getSavedValues方法上，我得到了错误

On the getSavedValues method I get the error

java.lang.RuntimeException：无法启动活动ComponentInfo {...}：java.lang.ClassCastException：java.lang.String无法转换为java.lang。整数

java.lang.RuntimeException: Unable to start activity ComponentInfo{...}: java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer

我不明白的是我将值保存为int并尝试以相同方式检索它们的事实。

What I don't understand is the fact that I save the value as int and try to retrieve them the same way.

此外，我也有类似的方法，但是使用 booleans 即可，而且效果很好。

Also, I have a similar method but with booleans and it works just fine.

推荐答案

我设法解决了该问题。代码没有什么错，但是它的值是在该应用的先前版本中编写的。

I managed to fix the issue. There was nothing wrong with the code, but with a value that was written in a previous version of the app.

在清理应用程序数据并在Android Studio中无效并清除缓存后，问题消失了。

After cleaning the app data and and Invalidate and clear cache in Android Studio the issue disappeared.

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