除了少数设备外，我的应用运行良好。在这样的设备上，我的一项 Activity 出现了致命异常。错误是 java.lang.ClassCastException: java.lang.String cannot be cast to android.text.Spannable ... ... at android.widget.TextView.setEnabled(TextView. java:1432)

堆栈跟踪

05-02 09:18:19.917: E/AndroidRuntime(20587): FATAL EXCEPTION: main
05-02 09:18:19.917: E/AndroidRuntime(20587): java.lang.ClassCastException: java.lang.String cannot be cast to android.text.Spannable
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.widget.TextView.setEnabled(TextView.java:1432)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at com.myapp.android.menu.LoginFragment.checkIfAnyFieldIsEmpty(LoginFragment.java:512)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at com.myapp.android.menu.LoginFragment.onCreateView(LoginFragment.java:183)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:429)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.os.Handler.handleCallback(Handler.java:615)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.os.Handler.dispatchMessage(Handler.java:92)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.os.Looper.loop(Looper.java:137)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at android.app.ActivityThread.main(ActivityThread.java:4962)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at java.lang.reflect.Method.invokeNative(Native Method)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at java.lang.reflect.Method.invoke(Method.java:511)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1004)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:771)
05-02 09:18:19.917: E/AndroidRuntime(20587):    at dalvik.system.NativeStart.main(Native Method)

以下是围绕该错误的代码 fragment 。

XML 布局代码

<com.myapp.android.view.StyledButton
        android:id="@+id/login_sign_in"
        style="@style/button_blue"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/state_list_login"
        android:textColor="@color/white"
        android:imeOptions="actionDone"
        android:padding="10dp"
        android:text="@string/sign_in" />

自定义按钮 JAVA 代码

public class StyledButton extends Button {
//variables
private final String BOLD = "fonts/arial.ttf";
private final String NORMAL = "fonts/arial_bold.ttf";

private String mCustomFont = null;

/**
 * Constructor
 * @param context
 */
public StyledButton(Context context) {
    super(context);
}

/**
 * Constructor
 * @param context
 * @param attrs
 */
public StyledButton(Context context, AttributeSet attrs) {
    super(context, attrs);
    setCustomAttributes(attrs);
}

/**
 * Set custom attributes
 * @param attrs
 */
private void setCustomAttributes(AttributeSet attrs) {
    TypedArray a=getContext().obtainStyledAttributes(attrs,R.styleable.StyledTextView);
    mCustomFont = a.getString(R.styleable.StyledTextView_fontAsset);
    if(mCustomFont != null) {
        if(!isInEditMode()) {
            CustomFontManager fontManager = CustomFontManager.getInstance();
            super.setTypeface(fontManager.getFont(getContext().getAssets(), mCustomFont));
        }
    }
    a.recycle();
}

/**
 * Set type face
 */
public void setTypeface(Typeface tf, int style) {
    CustomFontManager fontManager = CustomFontManager.getInstance();
    if(isInEditMode()) {
        super.setTypeface(tf,style);
        return;
    }
    if(mCustomFont!=null) {
        super.setTypeface(fontManager.getFont(getContext().getAssets(), mCustomFont));
        return;
    }
    switch (style) {
        case Typeface.NORMAL:
            super.setTypeface(fontManager.getFont(getContext().getAssets(), NORMAL));
            break;
        case Typeface.BOLD:
            super.setTypeface(fontManager.getFont(getContext().getAssets(), BOLD));
            break;
        default:
            super.setTypeface(fontManager.getFont(getContext().getAssets(), NORMAL));
            break;
    }
}

JAVA 代码导致错误

    private StyledButton mSignIn;

    public void checkIfAnyFieldIsEmpty() {
    if (mEmailEmpty || mPasswordEmpty) {
        mSignIn.setEnabled(false);
    } else {
        mSignIn.setEnabled(true);
    } 
}

mSignIn.setEnabled(false) 代码行导致错误。如果我将其注释掉或只是替换它，那么 if 和 else 都读取 mSignIn.setEnabled(true) 应用程序运行正常。

再次。代码在大多数设备上都可以正常工作。

最佳答案

您是否将您的样式按钮设置为可跨越？比如TextView应该是这样的

TextView.setText("海", TextView.BufferType.SPANANABLE);

关于android - 致命异常 : String can't be cast to Spannable，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/16340681/