我正在尝试使用SharedPreferences,但偶然发现了我的一个愚蠢错误。这是我的代码(MainActivity类):

private Boolean checkSSID;
private String connectionSSID;
private int leftPort;
private int rightPort;
private int LLUPort;
private int localUDPPort;
private String platformIPAddrStr;


在onCreate()方法的底部:

PreferenceManager.setDefaultValues(this, R.xml.preferences, false);

SharedPreferences sharedPref =
        PreferenceManager.getDefaultSharedPreferences(this);

checkSSID = sharedPref.getBoolean
        (SettingsActivity.KEY_PREF_CHECK_SSID, false);

connectionSSID = sharedPref.getString
        (SettingsActivity.KEY_PREF_CONNECTION_SSID, "\"bulldog\"");

leftPort = sharedPref.getInt
        (SettingsActivity.KEY_PREF_LEFT_UDP_PORT, 4001);

rightPort = sharedPref.getInt
        (SettingsActivity.KEY_PREF_RIGHT_UDP_PORT, 4002);

LLUPort = sharedPref.getInt
        (SettingsActivity.KEY_PREF_LLU_UDP_PORT, 8888);

localUDPPort = sharedPref.getInt
        (SettingsActivity.KEY_PREF_LOCAL_UDP_PORT, 5555);

platformType = sharedPref.getInt
        (SettingsActivity.KEY_PREF_PLATFORM_TYPE,0);


在第一个getInt()调用应用程序崩溃,并显示以下错误:

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


PreferenceScreen布局:

<PreferenceScreen xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android">

    <android.support.v7.preference.SwitchPreferenceCompat
        android:defaultValue="true"
        android:key="checkSSID"
        android:summary="@string/checkSSID_summary"
        android:title="@string/checkSSID_title" />
    <EditTextPreference
        android:defaultValue="bulldog"
        android:key="connectionSSID"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/LLUUDPPort_summary"
        android:title="@string/LLUUDPPort_title" />
    <EditTextPreference
        android:defaultValue="192.168.1.40"
        android:key="platformIPAddr"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/PlatformIPAddr_summary"
        android:title="@string/PlatformIPAddr_title" />
    <ListPreference
        android:defaultValue="1"
        android:entries="@array/PlatformType_titles"
        android:entryValues="@array/PlatformType_values"
        android:key="platformType"
        android:summary="@string/PlatformType_summary"
        android:title="@string/PlatformType_title" />
    <EditTextPreference
        android:defaultValue="4001"
        android:key="leftBankUDPPort"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/LeftBankUDPPort_summary"
        android:title="@string/LeftBankUDPPort_title" />
    <EditTextPreference
        android:defaultValue="4002"
        android:key="rightBankUDPPort"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/RightBankUDPPort_summary"
        android:title="@string/RightBankUDPPort_title" />
    <EditTextPreference
        android:defaultValue="8888"
        android:key="LLUUDPPort"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/LLUUDPPort_summary"
        android:title="@string/LLUUDPPort_title" />
    <EditTextPreference
        android:defaultValue="5555"
        android:key="localUDPPort"
        android:selectAllOnFocus="true"
        android:singleLine="true"
        android:summary="@string/localUDPPort_summary"
        android:title="@string/localUDPPort_title" />
</PreferenceScreen>


在SettingsActivity中,我声明了用于重新调用首选项键的所有公共字符串。即:

public static final String
        KEY_PREF_CHECK_SSID = "checkSSID";


我哪里失败了?

最佳答案

EditTextPreference返回String值,例如ListPreference。您需要将从共享首选项中提取的每个值从String转换为int。例如:

platformType  = Integer.valueOf(sharedPref.getString
        (SettingsActivity.KEY_PREF_PLATFORM_TYPE,"0"));

关于java - getInt中的Android SharedPreferences异常,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/52631681/

10-10 01:31