尝试使用自定义 EditText 时应用程序崩溃

Question

我正在使用自定义 editText，一开始就很喜欢。它也破坏了我在 xml 的设计页面上的限制。默认情况下一切正常。

自定义EditText代码：最后用它来锁定光标。

class CustomEditText(context: Context) : EditText(context) {

    public override fun onSelectionChanged(start: Int, end: Int) {
        val text = text
        if (text != null) {
            if (start != text.length || end != text.length) {
                setSelection(text.length, text.length)
                return
            }
        }

        super.onSelectionChanged(start, end)
    }
}

xml中的代码：

<sh1gure.test.creditcardform.view.CustomEditText
    android:id="@+id/etCardDate"
    android:layout_width="0dp"
    android:layout_height="50dp"
    android:layout_marginEnd="8dp"
    android:background="@drawable/edit_text_back"
    android:ems="10"
    android:hint="@string/mm_yy"
    android:inputType="number"
    android:maxLength="@integer/max_length_date"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"
    app:layout_constraintBottom_toTopOf="@+id/btn_add_card"
    app:layout_constraintEnd_toStartOf="@+id/etCardCvv"
    app:layout_constraintHorizontal_bias="0.5"
    app:layout_constraintStart_toStartOf="@+id/etCardNumber1"
    app:layout_constraintTop_toBottomOf="@+id/textView3" />

Logcat:

Process: sh1gure.test.creditcardform, PID: 24143
java.lang.RuntimeException: Unable to start activity ComponentInfo{sh1gure.test.creditcardform/sh1gure.test.creditcardform.view.MainActivity}: android.view.InflateException: Binary XML file line #53: Binary XML file line #53: Error inflating class sh1gure.test.creditcardform.view.CustomEditText
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2925)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3060)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1818)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:193)
    at android.app.ActivityThread.main(ActivityThread.java:6762)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
 Caused by: android.view.InflateException: Binary XML file line #53: Binary XML file line #53: Error inflating class sh1gure.test.creditcardform.view.CustomEditText
 Caused by: android.view.InflateException: Binary XML file line #53: Error inflating class sh1gure.test.creditcardform.view.CustomEditText

Answer 1

对于XML inflation，您必须提供一个带有AttributeSet作为第二个参数的构造函数：

class CustomEditText(context: Context, attrs: AttributeSet? = null) : EditText(context, attrs) {

    public override fun onSelectionChanged(start: Int, end: Int) {
        val text = text
        if (text != null) {
            if (start != text.length || end != text.length) {
                setSelection(text.length, text.length)
                return
            }
        }

        super.onSelectionChanged(start, end)
    }
}

尝试使用自定义 EditText 时应用程序崩溃

App crashing when I'm trying to use custom EditText

android

android-edittext

kotlin