Following the deal with a nested ListView EditText problem occurs, there is a problem EditText of the ListView setOnItemClickListener callback fails, read the latest source code, draw some conclusions, please point out any errors, you do not need to see the complete code, see the mark the key on the line.
1. Let's look at this step by step process callback
首先我们看到，这个回调发生在ListView的父类AdapterView的performItemClick中，下面是源码
/**
* Call the OnItemClickListener, if it is defined. Performs all normal
* actions associated with clicking: reporting accessibility event, playing
* a sound, etc.
*
* @param view The view within the AdapterView that was clicked.
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
* @return True if there was an assigned OnItemClickListener that was
* called, false otherwise is returned.
*/
public boolean performItemClick(View view, int position, long id) {
final boolean result;
if (mOnItemClickListener != null) {
playSoundEffect(SoundEffectConstants.CLICK);
mOnItemClickListener.onItemClick(this, view, position, id);
result = true;
} else {
result = false;
}
if (view != null) {
view.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_CLICKED);
}
return result;
}2. We look at where is called performItemClick, can be seen in the AbsListView
private class PerformClick extends WindowRunnnable implements Runnable {
int mClickMotionPosition;
@Override
public void run() {
// The data has changed since we posted this action in the event queue,
// bail out before bad things happen
if (mDataChanged) return;
final ListAdapter adapter = mAdapter;
final int motionPosition = mClickMotionPosition;
if (adapter != null && mItemCount > 0 &&
motionPosition != INVALID_POSITION &&
motionPosition < adapter.getCount() && sameWindow() &&
adapter.isEnabled(motionPosition)) {
final View view = getChildAt(motionPosition - mFirstPosition);
// If there is no view, something bad happened (the view scrolled off the
// screen, etc.) and we should cancel the click
if (view != null) {
//这里这里这里！！！！！
performItemClick(view, motionPosition, adapter.getItemId(motionPosition));
}
}
}
}3. Of course, there is the use of threads, and then look at where to start, the result was there in this class
private void onTouchUp(MotionEvent ev) {
switch (mTouchMode) {
case TOUCH_MODE_DOWN:
case TOUCH_MODE_TAP:
case TOUCH_MODE_DONE_WAITING:
final int motionPosition = mMotionPosition;
final View child = getChildAt(motionPosition - mFirstPosition);
if (child != null) {
if (mTouchMode != TOUCH_MODE_DOWN) {
child.setPressed(false);
}
final float x = ev.getX();
final boolean inList = x > mListPadding.left && x < getWidth() - mListPadding.right;
//！！！！！！！！！！
if (inList && !child.hasExplicitFocusable()) {
if (mPerformClick == null) {
mPerformClick = new PerformClick();
}
final AbsListView.PerformClick performClick = mPerformClick;
performClick.mClickMotionPosition = motionPosition;
performClick.rememberWindowAttachCount();
mResurrectToPosition = motionPosition;
if (mTouchMode == TOUCH_MODE_DOWN || mTouchMode == TOUCH_MODE_TAP) {
removeCallbacks(mTouchMode == TOUCH_MODE_DOWN ?
mPendingCheckForTap : mPendingCheckForLongPress);
mLayoutMode = LAYOUT_NORMAL;
if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
mTouchMode = TOUCH_MODE_TAP;
setSelectedPositionInt(mMotionPosition);
layoutChildren();
child.setPressed(true);
positionSelector(mMotionPosition, child);
setPressed(true);
if (mSelector != null) {
Drawable d = mSelector.getCurrent();
if (d != null && d instanceof TransitionDrawable) {
((TransitionDrawable) d).resetTransition();
}
mSelector.setHotspot(x, ev.getY());
}
if (mTouchModeReset != null) {
removeCallbacks(mTouchModeReset);
}
mTouchModeReset = new Runnable() {
@Override
public void run() {
mTouchModeReset = null;
mTouchMode = TOUCH_MODE_REST;
child.setPressed(false);
setPressed(false);
if (!mDataChanged && !mIsDetaching && isAttachedToWindow()) {
performClick.run();
}
}
};
postDelayed(mTouchModeReset,
ViewConfiguration.getPressedStateDuration());
} else {
mTouchMode = TOUCH_MODE_REST;
updateSelectorState();
}
return;
} else if (!mDataChanged && mAdapter.isEnabled(motionPosition)) {
//线程在这里被启动！！！！！！！！！！！
performClick.run();
}
}
}
mTouchMode = TOUCH_MODE_REST;
updateSelectorState();
break;The above code does not complete the interception, but this part is enough, It was found that the problem lies in the above first continuous! Mark, namely
inList &&! Child.hasExplicitFocusable (), according to debug found inList to true, the question on the right! Child.hasExplicitFocusable () is false cause the following code did not execute, performclick not started, that is, child.hasExplicitFocusable () is true, the code follows the method of
只要自己或自己里面的的View有明确的可获得焦点的都会返回true
/**
* Returns true if this view is focusable or if it contains a reachable View
* for which {@link #hasExplicitFocusable()} returns {@code true}.
* A "reachable hasExplicitFocusable()" is a view whose parents do not block descendants focus.
* Only {@link #VISIBLE} views for which {@link #getFocusable()} would return
* {@link #FOCUSABLE} are considered focusable.
*
* <p>This method preserves the pre-{@link Build.VERSION_CODES#O} behavior of
* {@link #hasFocusable()} in that only views explicitly set focusable will cause
* this method to return true. A view set to {@link #FOCUSABLE_AUTO} that resolves
* to focusable will not.</p>
*
* @return {@code true} if the view is focusable or if the view contains a focusable
* view, {@code false} otherwise
*
* @see #hasFocusable()
*/
public boolean hasExplicitFocusable() {
return hasFocusable(false, true);
}
boolean hasFocusable(boolean allowAutoFocus, boolean dispatchExplicit) {
if (!isFocusableInTouchMode()) {
for (ViewParent p = mParent; p instanceof ViewGroup; p = p.getParent()) {
final ViewGroup g = (ViewGroup) p;
if (g.shouldBlockFocusForTouchscreen()) {
return false;
}
}
}
// Invisible and gone views are never focusable.
if ((mViewFlags & VISIBILITY_MASK) != VISIBLE) {
return false;
}
//debug发现最终代码执行到了这个if语句里面，说明这个if是成立的
// Only use effective focusable value when allowed.
if ((allowAutoFocus || getFocusable() != FOCUSABLE_AUTO) && isFocusable()) {
return true;
}
return false;
}The documentation
IF The IF View The IS's focusable or the contains A's focusable View
View, {} @code otherwise to false
means that if the View is or comprises a focusable focusable View returns True, verified EditText it is the default focusable, which makes the method returns true, so child.hasExplicitFocusable () is true, it caused the callback can not be executed.
This callback can be seen in onTouchUp be called in, but onTouchUp in OnTouchEvent, the received event is called when ACTION_UP
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (!isEnabled()) {
// A disabled view that is clickable still consumes the touch
// events, it just doesn't respond to them.
return isClickable() || isLongClickable();
}
if (mPositionScroller != null) {
mPositionScroller.stop();
}
if (mIsDetaching || !isAttachedToWindow()) {
// Something isn't right.
// Since we rely on being attached to get data set change notifications,
// don't risk doing anything where we might try to resync and find things
// in a bogus state.
return false;
}
startNestedScroll(SCROLL_AXIS_VERTICAL);
if (mFastScroll != null && mFastScroll.onTouchEvent(ev)) {
return true;
}
initVelocityTrackerIfNotExists();
final MotionEvent vtev = MotionEvent.obtain(ev);
final int actionMasked = ev.getActionMasked();
if (actionMasked == MotionEvent.ACTION_DOWN) {
mNestedYOffset = 0;
}
vtev.offsetLocation(0, mNestedYOffset);
switch (actionMasked) {
case MotionEvent.ACTION_DOWN: {
onTouchDown(ev);
break;
}
case MotionEvent.ACTION_MOVE: {
onTouchMove(ev, vtev);
break;
}
/**
！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！！这里
*/
case MotionEvent.ACTION_UP: {
onTouchUp(ev);
break;
}By adding OnClick Item ViewGroup to the outer layer, according to the event distribution rules, the item will give priority to internal events, can not handle and threw a parent control,
it can respond to onclick callback, and then throw event ListView, ListView will consume just event (onTouchEvent returns true) but does not handle clicks callback
Analysis to end here, not a lot of class involved, just look at a few of the most critical method on the line, if there is not welcome that