@Test
public void testFindPositionOffsetInPreLayout() {
setupBasic(50, 25, 10);
rm(24, 5);
mAdapterHelper.preProcess();
// since 25 is invisible, we offset by one while checking
assertEquals("find position for view 23", 23, mAdapterHelper.findPositionOffset(23));
assertEquals("find position for view 24", -1, mAdapterHelper.findPositionOffset(24));
assertEquals("find position for view 25", -1, mAdapterHelper.findPositionOffset(25));
assertEquals("find position for view 26", -1, mAdapterHelper.findPositionOffset(26));
assertEquals("find position for view 27", -1, mAdapterHelper.findPositionOffset(27));
assertEquals("find position for view 28", 24, mAdapterHelper.findPositionOffset(28));
assertEquals("find position for view 29", 25, mAdapterHelper.findPositionOffset(29));
}
void preProcess() {
for (MockViewHolder vh : mViewHolders) {
final int ind = mTestAdapter.mItems.indexOf(vh.mItem);
assertEquals(
"actual adapter position should match",
ind,
mAdapterHelper.applyPendingUpdatesToPosition(vh.mPosition));
}
mAdapterHelper.preProcess();
for (int i = 0; i < mPreProcessClone.mItems.size(); i++) {
TestAdapter.Item item = mPreProcessClone.mItems.get(i);
final int preLayoutIndex = mPreLayoutItems.indexOf(item);
final int endIndex = mTestAdapter.mItems.indexOf(item);
if (preLayoutIndex != -1) {
assertEquals(
"find position offset should work properly for existing elements"
+ i
+ " at pre layout position "
+ preLayoutIndex
+ " and post layout position "
+ endIndex,
endIndex,
mAdapterHelper.findPositionOffset(preLayoutIndex));
}
}
// make sure visible view holders still have continuous positions
final StringBuilder vhLogBuilder = new StringBuilder();
for (ViewHolder vh : mViewHolders) {
vhLogBuilder.append("\n").append(vh.toString());
}
if (mViewHolders.size() > 0) {
final String vhLog = vhLogBuilder.toString();
final int start = mViewHolders.get(0).getLayoutPosition();
for (int i = 1; i < mViewHolders.size(); i++) {
assertEquals(
"view holder positions should be continious in pre-layout" + vhLog,
start + i,
mViewHolders.get(i).getLayoutPosition());
}
}
mAdapterHelper.consumePostponedUpdates();
// now assert these two adapters have identical data.
mPreProcessClone.applyOps(mFirstPassUpdates, mTestAdapter);
mPreProcessClone.applyOps(mSecondPassUpdates, mTestAdapter);
assertAdaptersEqual(mTestAdapter, mPreProcessClone);
}