Question

我在数组列表中的按钮上设置了侦听器时遇到了一个很奇怪的问题。我有一个似乎不起作用的for循环。我按下的任何按钮都会使应用崩溃。下面的代码仅定义了一个按钮，尽管如此，它仍无法完成工作... 我究竟做错了什么？

XML布局

<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:rowCount="20"
    android:columnCount="9">

    <Button
        android:id="@+id/jeton1"
        android:layout_column="0"
        android:layout_row="0"
        android:text="@string/boutona"
        android:layout_height="88dp"
        android:layout_width="88dp"
        android:textSize="40sp"
        android:backgroundTint="#eeceac"
        android:textStyle="bold" />

Java主类

public class MainActivity extends AppCompatActivity {

// Step 1 Array creation
private static final int[] idArray = {R.id.jeton1};

// Step 2 Set
private Button[] jeton = new Button[idArray.length];

int i;

@SuppressLint("ClickableViewAccessibility")
@Override

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Step 3 Assign array objects to buttons

    for (i=0; i <idArray.length ; i++){
        jeton[i] = (Button)findViewById(idArray[i]);

        // Step 4 Action listener

        jeton[i].setOnTouchListener(
                new View.OnTouchListener() {
                    @Override
                    public boolean onTouch(View view, MotionEvent event) {
                        switch (event.getAction()) {
                            case MotionEvent.ACTION_UP:
                                jeton[i].getBackground().setAlpha(0); // Crashes the app
                                jeton[i].setTextColor(Color.parseColor("#2aa17b"));
                                break;
                                                       }
                        return true;
                    }

    });

}

}}

该行：jeton [i] .getBackground（）。setAlpha（0）;导致应用崩溃

（java.lang.ArrayIndexOutOfBoundsException：length = 1; index = 1）

Logcat日志：

07-30 16:39:41.686 3964-3964/com.example.namour.combiendejetons W/art: Before Android 4.1, method int android.support.v7.widget.DropDownListView.lookForSelectablePosition(int, boolean) would have incorrectly overridden the package-private method in android.widget.ListView

07-30 16：39：41.714 3964-3964 / com.example.namour.combiendejetons I /时间轴：时间轴：Activity_idle ID：android.os.BinderProxy@25c2780e时间：76491516 07-30 16：39：44.172 3964-3964 / com.example.namour.combiendejetons I / ViewRootImpl：ViewRoot的Touch事件：ACTION_DOWN 07-30 16：39：44.201 3964-3964 / com.example.namour.combiendejetons I / ViewRootImpl：ViewRoot的Touch事件：ACTION_POINTER_DOWN（1） 07-30 16：39：44.228 3964-3964 / com.example.namour.combiendejetons I / ViewRootImpl：ViewRoot的Touch事件：ACTION_POINTER_UP（1） 07-30 16：39：44.273 3964-3964 / com.example.namour.combiendejetons I / ViewRootImpl：ViewRoot的Touch事件：ACTION_UP 07-30 16：39：44.291 3964-3964 / com.example.namour.combiendejetons E / InputEventReceiver：调度输入事件的异常。 07-30 16：39：44.292 3964-3964 / com.example.namour.combiendejetons E / MessageQueue-JNI：MessageQueue回调中的异常：handleReceiveCallback 07-30 16：39：44.302 3964-3964 / com.example.namour.combiendejetons E / MessageQueue-JNI：java.lang.ArrayIndexOutOfBoundsException：length = 1;索引= 1 在com.example.namour.combiendejetons.MainActivity $ 1.onTouch（MainActivity.java:45）在android.view.View.dispatchTouchEvent（View.java:8389）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在com.android.internal.policy.impl.PhoneWindow $ DecorView.superDispatchTouchEvent（PhoneWindow.java:2376）在com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent（PhoneWindow.java:1727）在android.app.Activity.dispatchTouchEvent（Activity.java:2783）在android.support.v7.view.WindowCallbackWrapper.dispatchTouchEvent（WindowCallbackWrapper.java:69）在com.android.internal.policy.impl.PhoneWindow $ DecorView.dispatchTouchEvent（PhoneWindow.java:2337）在android.view.View.dispatchPointerEvent（View.java:8585）在android.view.ViewRootImpl $ ViewPostImeInputStage.processPointerEvent（ViewRootImpl.java:4074）在android.view.ViewRootImpl $ ViewPostImeInputStage.onProcess（ViewRootImpl.java:3940）在android.view.ViewRootImpl $ InputStage.deliver（ViewRootImpl.java:3485）在android.view.ViewRootImpl $ InputStage.onDeliverToNext（ViewRootImpl.java:3538）在android.view.ViewRootImpl $ InputStage.forward（ViewRootImpl.java:3504）在android.view.ViewRootImpl $ InputStage.apply（ViewRootImpl.java:3512）在android.view.ViewRootImpl $ InputStage.deliver（ViewRootImpl.java:3485）在android.view.ViewRootImpl $ InputStage.onDeliverToNext（ViewRootImpl.java:3538）在android.view.ViewRootImpl $ InputStage.forward（ViewRootImpl.java:3504）在android.view.ViewRootImpl $ AsyncInputStage.forward（ViewRootImpl.java:3614）在android.view.ViewRootImpl $ InputStage.apply（ViewRootImpl.java:3512）在android.view.ViewRootImpl $ AsyncInputStage.apply（ViewRootImpl.java:3671）在android.view.ViewRootImpl $ InputStage.deliver（ViewRootImpl.java:3485）在android.view.ViewRootImpl $ InputStage.onDeliverToNext（ViewRootImpl.java:3538）在android.view.ViewRootImpl $ InputStage.forward（ViewRootImpl.java:3504）在android.view.ViewRootImpl $ InputStage.apply（ViewRootImpl.java:3512）在android.view.ViewRootImpl $ InputStage.deliver（ViewRootImpl.java:3485）在android.view.ViewRootImpl.deliverInputEvent（ViewRootImpl.java:5759）在android.view.ViewRootImpl.doProcessInputEvents（ViewRootImpl.java:5733）在android.view.ViewRootImpl.enqueueInputEvent（ViewRootImpl.java:5704）在android.view.ViewRootImpl $ WindowInputEventReceiver.onInputEvent（ViewRootImpl.java:5878）在android.view.InputEventReceiver.dispatchInputEvent（InputEventReceiver.java:185）在android.os.MessageQueue.nativePollOnce（本地方法）在android.os.MessageQueue.next（MessageQueue.java:143）在android.os.Looper.loop（Looper.java:122）在android.app.ActivityThread.main（ActivityThread.java:5272）在java.lang.reflect.Method.invoke（本机方法）在java.lang.reflect.Method.invoke（Method.java:372）在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:909）在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:704） 07-30 16：39：44.302 3964-3964 / com.example.namour.combiendejetons D / AndroidRuntime：关闭VM 07-30 16：39：44.304 3964-3964 / com.example.namour.combiendejetons E / AndroidRuntime：FATAL EXCEPTION：main 流程：com.example.namour.combiendejetons，PID：3964 java.lang.ArrayIndexOutOfBoundsException：length = 1;索引= 1 在com.example.namour.combiendejetons.MainActivity $ 1.onTouch（MainActivity.java:45 ）在android.view.View.dispatchTouchEvent（View.java:8389）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）在android.view.ViewGroup.dispatchTouchEvent（ViewGroup.java:2172）在android.view.ViewGroup.dispatchTransformedTouchEvent（ViewGroup.java:2430）

非常感谢您的答复

Java OnTouchListener无法获取数组项

0 个答案: