void updateText(int currentItem, PagerAdapter adapter) {
final int itemCount = adapter != null ? adapter.getCount() : 0;
mUpdatingText = true;
CharSequence text = null;
if (currentItem >= 1 && adapter != null) {
text = adapter.getPageTitle(currentItem - 1);
}
mPrevText.setText(text);
mCurrText.setText(adapter != null ? adapter.getPageTitle(currentItem) : null);
text = null;
if (currentItem + 1 < itemCount && adapter != null) {
text = adapter.getPageTitle(currentItem + 1);
}
mNextText.setText(text);
// Measure everything
final int width = getWidth() - getPaddingLeft() - getPaddingRight();
final int childHeight = getHeight() - getPaddingTop() - getPaddingBottom();
final int childWidthSpec =
MeasureSpec.makeMeasureSpec((int) (width * 0.8f), MeasureSpec.AT_MOST);
final int childHeightSpec = MeasureSpec.makeMeasureSpec(childHeight, MeasureSpec.EXACTLY);
mPrevText.measure(childWidthSpec, childHeightSpec);
mCurrText.measure(childWidthSpec, childHeightSpec);
mNextText.measure(childWidthSpec, childHeightSpec);
mLastKnownCurrentPage = currentItem;
if (!mUpdatingPositions) {
updateTextPositions(currentItem, mLastKnownPositionOffset);
}
mUpdatingText = false;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
final ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
viewPager = (ViewPager) findViewById(R.id.pager);
PagerAdapter adapter = new PagerAdapter(getSupportFragmentManager(), this);
viewPager.setAdapter(adapter);
viewPager.setOnPageChangeListener(
new ViewPager.SimpleOnPageChangeListener() {
@Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
});
for (int i = 0; i < adapter.getCount(); i++) {
actionBar.addTab(actionBar.newTab().setText(adapter.getPageTitle(i)).setTabListener(this));
}
}