在遇到的坑之前我们先了解 Android onTouchEvent, onClick及onLongClick的调用机制
1. onTouchEvent:
onTouchEvent中要处理的最常用的3个事件就是:ACTION_DOWN(按下)、ACTION_MOVE(移动)、ACTION_UP(抬起)。
2. onClick、onLongClick与onTouchEvent
在Android中,onClick、onLongClick的触发是和ACTION_DOWN及ACTION_UP相关的,在时序上,如果我们在一个View中同时覆写了onClick、onLongClick及onTouchEvent的话,onTouchEvent是最先捕捉到ACTION_DOWN和ACTION_UP事件的,其次才可能触发onClick或者onLongClick。主要的逻辑在View.java中的onTouchEvent方法中实现的,主要的操作是在View.onTucchEvent下的: switch (event.getAction()) { case MotionEvent.ACTION_UP: boolean prepressed = (mPrivateFlags & PFLAG_PREPRESSED) != 0; if ((mPrivateFlags & PFLAG_PRESSED) != 0 || prepressed) { // take focus if we don't have it already and we should in // touch mode. boolean focusTaken = false; if (isFocusable() && isFocusableInTouchMode() && !isFocused()) { focusTaken = requestFocus(); } if (prepressed) { // The button is being released before we actually // showed it as pressed. Make it show the pressed // state now (before scheduling the click) to ensure // the user sees it. setPressed(true, x, y); } if (!mHasPerformedLongPress) { // This is a tap, so remove the longpress check removeLongPressCallback(); // Only perform take click actions if we were in the pressed state if (!focusTaken) { // Use a Runnable and post this rather than calling // performClick directly. This lets other visual state // of the view update before click actions start. if (mPerformClick == null) { mPerformClick = new PerformClick(); } if (!post(mPerformClick)) { performClick(); } } } if (mUnsetPressedState == null) { mUnsetPressedState = new UnsetPressedState(); } if (prepressed) { postDelayed(mUnsetPressedState, ViewConfiguration.getPressedStateDuration()); } else if (!post(mUnsetPressedState)) { // If the post failed, unpress right now mUnsetPressedState.run(); } removeTapCallback(); } break; case MotionEvent.ACTION_DOWN: mHasPerformedLongPress = false; if (performButtonActionOnTouchDown(event)) { break; } // Walk up the hierarchy to determine if we're inside a scrolling container. boolean isInScrollingContainer = isInScrollingContainer(); // For views inside a scrolling container, delay the pressed feedback for // a short period in case this is a scroll. if (isInScrollingContainer) { mPrivateFlags |= PFLAG_PREPRESSED; if (mPendingCheckForTap == null) { mPendingCheckForTap = new CheckForTap(); } mPendingCheckForTap.x = event.getX(); mPendingCheckForTap.y = event.getY(); postDelayed(mPendingCheckForTap, ViewConfiguration.getTapTimeout()); } else { // Not inside a scrolling container, so show the feedback right away setPressed(true, x, y); checkForLongClick(0); } break; case MotionEvent.ACTION_CANCEL: setPressed(false); removeTapCallback(); removeLongPressCallback(); break; case MotionEvent.ACTION_MOVE: drawableHotspotChanged(x, y); // Be lenient about moving outside of buttons if (!pointInView(x, y, mTouchSlop)) { // Outside button removeTapCallback(); if ((mPrivateFlags & PFLAG_PRESSED) != 0) { // Remove any future long press/tap checks removeLongPressCallback(); setPressed(false); } } break;
可以看到,Click的触发是在系统捕捉到ACTION_UP后发生并由performClick()执行的;LongClick的触发则是从ACTION_DOWN开始,由checkForLongClick()方法完成的;
他们执行Touch事件的的顺序 ACTION_DOWN -> ACTION_UP -> OnClick/OnLongClick。
首先,该View会先响应ACTION_DOWN事件,并返回一个boolean值,这里有两种判断:
1. 返回true,表示该View接受此按下动作,就是说这个点击动作的按下操作被中止,然后就是响应ACTION_UP事件。点击动作的按下操作被ACTION_DOWN接受之后就结束了,所以之后的OnClick/OnLongClick事件就不会响应了。
返回false,表示该View不接受此按下动作,响应完之后,按下操作继续往下发,之后是响应ACTION_UP事件,这里又有一个判断:
如果ACTION_UP事件返回true,表示ACTION_UP接受松开操作,松开操作中止;View会一直处于按下状态,之后View便会响应OnLongClick事件。 如果ACTION_UP事件返回false,表示ACTION_UP不接收松开操作,松开操作继续下发;因为按下与松开操作都没有被中止,所以之后View就会响应OnClick事件。
下面就是我在魅族中踩的坑了:
手机在EditText长按进行粘贴,会触发OnLongClick 的事件,但是我在魅族的手机EditText长按进行粘贴,如果做了onTouchEvent监听,死活的都不会触发OnLongClick 的事件,不够onTouchEvent返回的是true还是false 都白费,当然也不会进行粘贴;其他的手机都是按照正常的节奏来,就只有魅族!
找到问题了现在就是怎么去解决问题,这里我用到onTouchEvent 主要监听的是ACTION_MOVE 的处理,既然onTuchEvent不行就只有用其方式来监听滑动了,用到的是GestureDetector.SimpleOnGestureListener 进行监听的 :
public static class SimpleOnGestureListener implements OnGestureListener, OnDoubleTapListener { // --------------OnGestureListener的接口有这几个---------------- // 抬起,手指离开触摸屏时触发(长按、滚动、滑动时,不会触发这个手势) public boolean onSingleTapUp(MotionEvent e) { return false; } // 长按,触摸屏按下后既不抬起也不移动,过一段时间后触发 public void onLongPress(MotionEvent e) { } // 滚动,触摸屏按下后移动 public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { return false; } // 滑动,触摸屏按下后快速移动并抬起,会先触发滚动手势,跟着触发一个滑动手势 public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { return false; } // 短按,触摸屏按下后片刻后抬起,会触发这个手势,如果迅速抬起则不会 public void onShowPress(MotionEvent e) { } // 单击,触摸屏按下时立刻触发 public boolean onDown(MotionEvent e) { return false; } //------------------------OnDoubleTapListener的接口有这几个----------- // 双击,手指在触摸屏上迅速点击第二下时触发 public boolean onDoubleTap(MotionEvent e) { return false; } // 双击的按下跟抬起各触发一次 public boolean onDoubleTapEvent(MotionEvent e) { return false; } // 单击确认,即很快的按下并抬起,但并不连续点击第二下 public boolean onSingleTapConfirmed(MotionEvent e) { return false; } }
于是我重写我的EditText 继承EditText:
public class MyEditText extends EditText {private GestureDetector mGestureDetector;private SimpleOnGestureListener simpleOnGestureListener;private Context context;public MyEditText(Context context) { super(context); this.context = context; setLongClickable(true); }public void setMyGestureListener(SimpleOnGestureListener simpleOnGestureListener) { this.simpleOnGestureListener = simpleOnGestureListener; setGestureDetector(); }public MyEditText(Context context, AttributeSet attrs) { super(context, attrs); setLongClickable(true); this.context = context; }private void setGestureDetector() { mGestureDetector = new GestureDetector(context, simpleOnGestureListener); this.setOnTouchListener(new OnTouchListener() { public boolean onTouch(View v, MotionEvent event) { return mGestureDetector.onTouchEvent(event); } }); }
}
注意:
1.这里一定要记得设置longClickable为true, 否则手势识别无法正确工作,只会返回Down, Show, Long三种手势 2. 必须在View的onTouchListener中调用手势识别,而不能像Activity一样重载onTouchEvent,否则同样手势识别无法正确工作
最后这样就ok了:
mTvEditContent.setMyGestureListener(new SimpleOnGestureListener() { @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { // 处理我想做的 return super.onScroll(e1, e2, distanceX, distanceY); } });
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