首先,我知道有人多次询问过这个问题,但在较新的 Android 版本上,建议的解决方案似乎不起作用。 我需要我的微调器调用 OnItemSelected,即使用户两次选择相同的项目也是如此。 我发现这个类应该可以解决问题:
public class NDSpinner extends Spinner {
private int lastSelected = 0;
private static Method s_pSelectionChangedMethod = null;
static {
try {
Class noparams[] = {};
Class targetClass = AdapterView.class;
s_pSelectionChangedMethod = targetClass.getDeclaredMethod("selectionChanged", noparams);
if (s_pSelectionChangedMethod != null) {
s_pSelectionChangedMethod.setAccessible(true);
}
} catch( Exception e ) {
Log.e("Custom spinner, reflection bug:", e.getMessage());
throw new RuntimeException(e);
}
}
public NDSpinner(Context context) {
super(context);
}
public NDSpinner(Context context, AttributeSet attrs) {
super(context, attrs);
}
public NDSpinner(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if(this.lastSelected == this.getSelectedItemPosition())
testReflectionForSelectionChanged();
if(!changed)
lastSelected = this.getSelectedItemPosition();
super.onLayout(changed, l, t, r, b);
}
public void testReflectionForSelectionChanged() {
try {
Class noparams[] = {};
s_pSelectionChangedMethod.invoke(this, noparams);
} catch (Exception e) {
Log.e("Custom spinner, reflection bug: ", e.getMessage());
e.printStackTrace();
}
}
@Override
public void onClick(DialogInterface dialog, int which) {
super.onClick(dialog, which);
}
}
这实际上是有效的,但它有一个错误:它第一次调用了两次 item :( 谁能告诉我如何解决这个问题?
谢谢伙伴们。
最佳答案
我已经用这个类解决了:
public class NDSpinner extends Spinner {
public NDSpinner(Context context)
{ super(context); }
public NDSpinner(Context context, AttributeSet attrs)
{ super(context, attrs); }
public NDSpinner(Context context, AttributeSet attrs, int defStyle)
{ super(context, attrs, defStyle); }
@Override public void
setSelection(int position, boolean animate)
{
boolean sameSelected = position == getSelectedItemPosition();
super.setSelection(position, animate);
if (sameSelected) {
// Spinner does not call the OnItemSelectedListener if the same item is selected, so do it manually now
getOnItemSelectedListener().onItemSelected(this, getSelectedView(), position, getSelectedItemId());
}
}
@Override public void
setSelection(int position)
{
boolean sameSelected = position == getSelectedItemPosition();
super.setSelection(position);
if (sameSelected) {
// Spinner does not call the OnItemSelectedListener if the same item is selected, so do it manually now
getOnItemSelectedListener().onItemSelected(this, getSelectedView(), position, getSelectedItemId());
}
}
}
还是谢谢你:)
关于Android Spinner OnItemSelected 未使用同一项目调用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19734099/