Q:在做多點觸控放大縮小，操作自己所繪制的圖形時發(fā)生這個異常

A:bug是Android系統(tǒng)原因

1.修改frameworks\base\core\jni\android_view_MotionEvent.cpp
的android_view_MotionEvent_nativeGetAxisValue方法注釋掉

if (!validatePointerIndex(env, pointerIndex, pointerCount)) 
{return 0;｝

2.捕獲IllegalArgumentException異常

private float spacing(MotionEvent event) {
    try {
        x = event.getX(0) - event.getX(1);
        y = event.getY(0) - event.getY(1);
    } catch (IllegalArgumentException e) {      
        e.printStackTrace();
    }