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如何從不同的類（活動或片段）訪問標籤條類？我想從其他地方改變它的背景顏色。如何從不同的類動態更改視圖背景顏色
當使用原標籤條類中的以下代碼它完美的作品：
mTabStrip.setBackgroundColor(ContextCompat.getColor(getContext(), R.color.blue));
我相信，這樣的事情需要使用，但我不知道如何訪問它（TabStrip控件類）來自另一個類（即活動或片段）並更改背景顏色。
XML活動佈局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/detail_container">
<include layout="@layout/my_toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<com.companyname.appname.TabStrip
android:id="@+id/my_tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_height="0dp"
android:layout_width="match_parent"
android:layout_weight="1"/>
</LinearLayout>
Activity類
public class MyActivity extends AppCompatActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_activity);
final String toolbarColour = "#868F98";
Toolbar customToolbar = findViewById(R.id.my_toolbar);
setActionBar(customToolbar);
customToolbar.setBackgroundColor(Color.parseColor(toolbarColour));
TextView mTitle = this.findViewById(R.id.toolbar_title);
mTitle.setText(getString(R.string.toolbar));
if (savedInstanceState == null) {
MyFragment newFragment = new MyFragment();
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(R.id.detail_container, newFragment);
transaction.commit();
}
}
}
MyFragment.java
public class MyFragment extends android.support.v4.app.Fragment {
public MyFragment() {}
ViewPager pager;
MyFragmentViewPagerAdapter adapter;
MyTabStrip my_tabs;
int Numboftabs = 3;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.my_fragment, container, false);
super.onCreate(savedInstanceState);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
View v = getView();
adapter = new MyFragmentViewPagerAdapter(getChildFragmentManager(), Numboftabs, getActivity());
assert v != null;
pager = v.findViewById(R.id.pager);
pager.setAdapter(adapter);
mytabs = v.findViewById(R.id.my_tabs);
mytabs.setDistributeEvenly(false);
my_tabs.setCustomTabColorizer(new TabStrip.TabColorizer() {
@Override
public int getIndicatorColor(int position) {
return Color.WHITE;
}
});
mytabs.setViewPager(pager);
super.onActivityCreated(savedInstanceState);
}
private class MyFragmentViewPagerAdapter extends FragmentStatePagerAdapter {
private int NumbOfTabs;
private Context context;
MyFragmentViewPagerAdapter(FragmentManager fm, int mNumbOfTabsumb, Context context) {
super(fm);
this.context = context;
this.NumbOfTabs = mNumbOfTabsumb;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return new Tab1();
case 1:
return new Tab2();
case 2:
return new Tab3();
}
return null;
}
@Override
public CharSequence getPageTitle(int position) {
switch (position) {
case 0:
return context.getResources().getString(R.string.tab_1);
case 1:
return context.getResources().getString(R.string.tab_2);
case 2:
return context.getResources().getString(R.string.tab_3);
}
return super.getPageTitle(position);
}
@Override
public int getCount() {
return NumbOfTabs;
}
}
}
TabStrip.java
public class TabStrip extends HorizontalScrollView {
public interface TabColorizer {
int getIndicatorColor(int position);
}
private static final int TITLE_OFFSET_DIPS = 24;
private static final int TAB_VIEW_PADDING_DIPS = 16;
private static final int TAB_VIEW_TEXT_SIZE_SP = 12;
private int mTitleOffset;
private int mTabViewLayoutId;
private int mTabViewTextViewId;
private boolean mDistributeEvenly;
private ViewPager mViewPager;
private SparseArray<String> mContentDescriptions = new SparseArray<>();
private ViewPager.OnPageChangeListener mViewPagerPageChangeListener;
private final SlidingTabStrip mTabStrip;
public TabStrip(Context context) {
this(context, null);
}
public TabStrip(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public TabStrip(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setHorizontalScrollBarEnabled(false);
setFillViewport(true);
mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);
mTabStrip = new SlidingTabStrip(context);
addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
}
public void setCustomTabColorizer(TabStrip.TabColorizer tabColorizer) {
mTabStrip.setCustomTabColorizer(tabColorizer);
}
public void setDistributeEvenly(boolean distributeEvenly) {
mDistributeEvenly = distributeEvenly;
}
public void setSelectedIndicatorColors(int... colors) {
mTabStrip.setSelectedIndicatorColors(colors);
}
public void addOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
mViewPagerPageChangeListener = listener;
}
public void setCustomTabView(int layoutResId, int textViewId) {
mTabViewLayoutId = layoutResId;
mTabViewTextViewId = textViewId;
}
public void setViewPager(ViewPager viewPager) {
mTabStrip.removeAllViews();
mViewPager = viewPager;
if (viewPager != null) {
viewPager.addOnPageChangeListener(new TabStrip.InternalViewPagerListener());
populateTabStrip();
}
}
protected TextView createDefaultTabView(Context context) {
TextView textView = new TextView(context);
textView.setGravity(Gravity.CENTER);
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
textView.setTypeface(Typeface.DEFAULT_BOLD);
textView.setLayoutParams(new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
TypedValue outValue = new TypedValue();
getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
outValue, true);
textView.setBackgroundResource(outValue.resourceId);
textView.setAllCaps(true);
int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
textView.setPadding(padding, padding, padding, padding);
return textView;
}
private void populateTabStrip() {
final PagerAdapter adapter = mViewPager.getAdapter();
final View.OnClickListener tabClickListener = new TabStrip.TabClickListener();
for (int i = 0; i < adapter.getCount(); i++) {
View tabView = null;
TextView tabTitleView = null;
if (mTabViewLayoutId != 0) {
tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip, false);
tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
}
if (tabView == null) {
tabView = createDefaultTabView(getContext());
}
if (tabTitleView == null && TextView.class.isInstance(tabView)) {
tabTitleView = (TextView) tabView;
}
if (mDistributeEvenly) {
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams();
lp.width = 0;
lp.weight = 1;
}
assert tabTitleView != null;
tabTitleView.setText(adapter.getPageTitle(i));
tabView.setOnClickListener(tabClickListener);
String desc = mContentDescriptions.get(i, null);
if (desc != null) {
tabView.setContentDescription(desc);
}
mTabStrip.addView(tabView);
if (i == mViewPager.getCurrentItem()) {
tabView.setSelected(true);
}
tabTitleView.setTextColor(Color.WHITE);
tabTitleView.setTextSize(14);
}
}
public void setContentDescription(int i, String desc) {
mContentDescriptions.put(i, desc);
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
if (mViewPager != null) {
scrollToTab(mViewPager.getCurrentItem(), 0);
}
}
private void scrollToTab(int tabIndex, int positionOffset) {
final int tabStripChildCount = mTabStrip.getChildCount();
if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) {
return;
}
View selectedChild = mTabStrip.getChildAt(tabIndex);
if (selectedChild != null) {
int targetScrollX = selectedChild.getLeft() + positionOffset;
if (tabIndex > 0 || positionOffset > 0) {
targetScrollX -= mTitleOffset;
}
scrollTo(targetScrollX, 0);
}
}
private class InternalViewPagerListener implements ViewPager.OnPageChangeListener {
private int mScrollState;
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
int tabStripChildCount = mTabStrip.getChildCount();
if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
return;
}
mTabStrip.onViewPagerPageChanged(position, positionOffset);
View selectedTitle = mTabStrip.getChildAt(position);
int extraOffset = (selectedTitle != null)
? (int) (positionOffset * selectedTitle.getWidth())
: 0;
scrollToTab(position, extraOffset);
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageScrolled(position, positionOffset,
positionOffsetPixels);
}
}
@Override
public void onPageScrollStateChanged(int state) {
mScrollState = state;
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageScrollStateChanged(state);
}
}
@Override
public void onPageSelected(int position) {
if (mScrollState == ViewPager.SCROLL_STATE_IDLE) {
mTabStrip.onViewPagerPageChanged(position, 0f);
scrollToTab(position, 0);
}
for (int i = 0; i < mTabStrip.getChildCount(); i++) {
mTabStrip.getChildAt(i).setSelected(position == i);
}
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageSelected(position);
}
}
}
private class TabClickListener implements View.OnClickListener {
@Override
public void onClick(View v) {
for (int i = 0; i < mTabStrip.getChildCount(); i++) {
if (v == mTabStrip.getChildAt(i)) {
mViewPager.setCurrentItem(i);
return;
}
}
}
}
}