我正在制作一个日期选择器 Activity ,看起来像滚动的 30 天月份/日历(想想 Outlook 日历)。日期选择器包含 MonthView View 的 ListView(用于滚动),每个 View 都是各个日期的 TableView。 MonthView 中的每一天都是一个按钮。当实例化 MonthView 时,我会遍历每一天(按钮)并附加一个点击监听器:
final Button b = getButtonAt(i);
b.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
setSelectedDate(buttonDayClosure, b);
}
});
setSelectedDate 可以执行多种操作,但它还会将按钮的背景变为黄色以表示已选择日期。
在我的模拟器上,一切都按您的预期运行。 Activity 来了,你按一天,一天就变成黄色。没问题。
但是,在我的一些同行的模拟器和物理设备上,当您触摸某一天时,什么也不会发生...直到您滚动 ListView...然后所选的一天突然变成黄色。因此,例如,您触摸“第三个”,然后什么也没有发生。等待几秒钟,然后滚动 ListView(触摸日历中不是第三个区域的区域),一旦 ListView 滚动,第三个区域就会神奇地变成黄色。
在显示此行为的对等模拟器上,我可以在 onClick 的第一行设置一个断点,并且我发现实际上直到 ListView 滚动才触发 BP。
这种行为对我来说没有任何意义。我希望 onClick 行为与封装 View 的滚动效果无关。
对于为什么会出现这种情况以及如何纠正这种情况有什么想法,以便在触摸按钮时 onClicks 总是立即发生?
谢谢。
Post Scriptus:请求 ArrayAdapter 和 ListView 代码:
public class MonthArrayAdapter extends ArrayAdapter<Date> {
private MonthView[] _views;
private Vector<Procedure<Date>> _dateSelectionChangedListeners = new Vector<Procedure<Date>>();
public MonthArrayAdapter(Context context, int textViewResourceId, Date minSelectableDay, Date maxSelectableDay) {
super(context, textViewResourceId);
int zeroBasedMonth = minSelectableDay.getMonth();
int year = 1900 + minSelectableDay.getYear();
if(minSelectableDay.after(maxSelectableDay))
{
throw new IllegalArgumentException("Min day cannot be after max day.");
}
Date prevDay = minSelectableDay;
int numMonths = 1;
for(Date i = minSelectableDay; !sameDay(i, maxSelectableDay); i = i.addDays(1) )
{
if(i.getMonth() != prevDay.getMonth())
{
numMonths++;
}
prevDay = i;
}
_views = new MonthView[numMonths];
for(int i = 0; i<numMonths; i++)
{
Date monthDate = new Date(new GregorianCalendar(year, zeroBasedMonth, 1, 0, 0).getTimeInMillis());
Date startSunday = findStartSunday(monthDate);
this.add(monthDate);
_views[i] = new MonthView(this.getContext(), startSunday, minSelectableDay, maxSelectableDay);
zeroBasedMonth++;
if(zeroBasedMonth == 12)
{
year++;
zeroBasedMonth = 0;
}
}
for(final MonthView a : _views)
{
a.addSelectedDateChangedListener(new Procedure<MonthView>()
{
@Override
public void execute(MonthView input) {
for(final MonthView b: _views)
{
if(a != b)
{
b.clearCurrentSelection();
}
}
for(Procedure<Date> listener : _dateSelectionChangedListeners)
{
listener.execute(a.getSelectedDate());
}
}
});
}
}
void addSelectedDateChangedListener(Procedure<Date> listener)
{
_dateSelectionChangedListeners.add(listener);
}
private boolean sameDay(Date a, Date b)
{
return a.getYear() == b.getYear() && a.getMonth() == b.getMonth() &&
a.getDate() == b.getDate();
}
@Override
public View getView (int position, View convertView, ViewGroup parent)
{
return _views[position];
}
private Date findStartSunday(Date d)
{
return d.subtractDays(d.getDay());
}
public void setSelectedDate(Date date)
{
for(MonthView mv : _views)
{
mv.setSelectedDate(date);
}
}
}
和
public class DatePicker extends ActivityBase {
public static final String CHOSEN_DATE_RESULT_KEY = "resultKey";
public static final String MIN_SELECTABLE_DAY = DatePicker.class.getName() + "MIN";
public static final String MAX_SELECTABLE_DAY = DatePicker.class.getName() + "MAX";
private static final String SELECTED_DATE = UUID.randomUUID().toString();
private long _selectedDate = -1;
private MonthArrayAdapter _monthArrayAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Date now = new Date();
Bundle inputs = this.getIntent().getExtras();
long min = inputs.getLong(MIN_SELECTABLE_DAY, 0);
Date minSelectableDate;
if(min == 0)
{
minSelectableDate = new Date(now);
}
else
{
minSelectableDate = new Date(min);
}
Log.i(DatePicker.class.getName(), "min date = " + minSelectableDate.toString());
long max = inputs.getLong(MAX_SELECTABLE_DAY, 0);
Date maxSelectableDate;
if(max == 0)
{
maxSelectableDate = new Date(now.addDays(35).getTime());
}
else
{
maxSelectableDate = new Date(max);
}
setContentView(R.layout.date_picker);
Button doneButton = (Button) findViewById(R.id.DatePickerDoneButton);
if(doneButton == null)
{
Log.e(this.getClass().getName(), "Could not find doneButton from view id.");
finish();
return;
}
doneButton.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
Intent result = new Intent();
result.putExtra(CHOSEN_DATE_RESULT_KEY, _selectedDate);
setResult(RESULT_OK, result);
finish();
}
});
Button cancelButton = (Button) findViewById(R.id.DatePickerCancelButton);
if(cancelButton == null)
{
Log.e(this.getClass().getName(), "Could not find cancelButton from view id.");
finish();
return;
}
cancelButton.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
setResult(RESULT_CANCELED, null);
finish();
}
});
ListView lv = (ListView)findViewById(R.id.DatePickerMonthListView);
lv.setDividerHeight(0);
_monthArrayAdapter =
new MonthArrayAdapter(this, android.R.layout.simple_list_item_1, minSelectableDate, maxSelectableDate);
_monthArrayAdapter.addSelectedDateChangedListener(new Procedure<Date>()
{
@Override
public void execute(Date input) {
_selectedDate = input.getTime();
}
});
lv.setAdapter(_monthArrayAdapter);
}
@Override
public void onRestoreInstanceState(Bundle savedInstanceState)
{
if(savedInstanceState.containsKey(SELECTED_DATE))
{
_selectedDate = savedInstanceState.getLong(SELECTED_DATE);
_monthArrayAdapter.setSelectedDate(new Date(_selectedDate));
}
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState)
{
savedInstanceState.putLong(SELECTED_DATE, _selectedDate);
}
}
最佳答案
遇到同样的问题,正在寻找答案。当我滚动列表之前没有得到 onClick 方法时,我完全不相信。如果我找到答案,我会在这里发布答案。
现在,我最好的猜测是尝试除单击之外的不同事件(因为滚动空间正在吞噬复杂的触摸事件,这些事件会变成单击事件):
“downView”是一个静态变量,用于跟踪被单击的元素。
view.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_DOWN) {
downView = v;
return true;
} else if (event.getAction() == MotionEvent.ACTION_UP) {
if (downView == v) {
handleClick(v);
return true;
}
downView = null;
}
return false;
}
});
关于Android:ListView 中的按钮未接收 onClick 事件,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/4327783/