android自定义tabhost实现选项卡功能
本例子借鉴与网上的部分内容，目的在于实现选项卡功能，自定义的添加选项卡，自动生成选项条，并且可以*设置选项卡颜色，设置字体大小，大部分功能都集成到自定义的类里面，我们以后碰到此类功能，只需要调用这个类即可
运行效果截图：
（1）新建一个xml，用于展示tabhost，注意红色部分为当前项目包名，需要根据实际情况修改：
<LinearLayout android:layout_width="match_parent" android:layout_height="50dp" android:gravity="center" > <com.example.administrator.testb.TabsView android:id="@+id/tabslayout" android:layout_width="match_parent" android:layout_height="wrap_content" /> </LinearLayout> <android.support.v4.view.ViewPager android:id="@+id/viewpager" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" />
（2）新建一个适配器的类MyAdapter，这个类用于实现选项卡滑动的效果
public class MyAdapter extends PagerAdapter { private List<View> list; public MyAdapter(List<View> list) { this.list = list; } @Override public int getCount() { if (list != null && list.size() > 0) { return list.size(); } else { return 0; } } @Override public boolean isViewFromObject(View arg0, Object arg1) { return arg0 == arg1; } @Override public void destroyItem(ViewGroup container, int position, Object object) { container.removeView((View) object); } @Override public Object instantiateItem(ViewGroup container, int position) { container.addView(list.get(position)); return list.get(position); } @Override public int getItemPosition(Object object) { return POSITION_NONE; } }
（3）在MainActivity中绑定控件，调用类的方法，并且设置适配器内容显示
//fragment效果，参考网址：https://blog.csdn.net/qq_33425116/article/details/52599818
//绑定控件 mViewPager = (ViewPager) findViewById(R.id.viewpager); mTabs = (TabsView) findViewById(R.id.tabslayout); views = new ArrayList<View>(); View view1 = getLayoutInflater().inflate(R.layout.item_one,null); View view2 = getLayoutInflater().inflate(R.layout.item_two,null); View view3 = getLayoutInflater().inflate(R.layout.item_three,null); View view4 = getLayoutInflater().inflate(R.layout.item_four,null); views.add(view1); views.add(view2); views.add(view3); views.add(view4); //设置适配器 adapter = new MyAdapter(views); mViewPager.setAdapter(adapter); //初始化选项卡 mTabs.setTabs("选项卡1","选项卡2","选项卡3","选项卡4"); mTabs.setOnTabsItemClickListener(new TabsView.OnTabsItemClickListener() { @Override public void onClick(View view, int position) { mViewPager.setCurrentItem(position, true); } }); //选项卡事件监听 mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() { @Override public void onPageSelected(int position) { mTabs.setCurrentTab(position, true); } @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageScrollStateChanged(int state) { } });（5）自定义的类TabsView，注意在xml中引用此类需要修改包名
public class TabsView extends LinearLayout { private int mSelectedColor = 0xff000000;// 选中的字体颜色 private int mNotSelectedColor = ((mSelectedColor >>> 25) << 24) | (mSelectedColor & 0x00ffffff);// 未选中的字体颜色 private int mIndicatorColor = 0xff00BFFF;// 指示器的颜色 private LinearLayout mTabsContainer;// 放置tab的容器 private View mIndicator, mBottomLine;// 指示器和底部横线 private OnTabsItemClickListener listener; public TabsView(Context context) { this(context, null); } public TabsView(Context context, AttributeSet attrs) { this(context, attrs, 0); } public TabsView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); setOrientation(VERTICAL); // 初始化容器 mTabsContainer = new LinearLayout(getContext()); mTabsContainer.setOrientation(HORIZONTAL); mTabsContainer.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); addView(mTabsContainer); // 初始化指示器 mIndicator = new View(getContext()); mIndicator.setBackgroundColor(mIndicatorColor); mIndicator.setLayoutParams(new LayoutParams(300, 8));// 先任意设置宽度 addView(mIndicator); // 初始化底部横线 mBottomLine = new View(getContext()); mBottomLine.setBackgroundColor(mIndicatorColor); mBottomLine.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, 4)); addView(mBottomLine); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); resetIndicator(); } /** * 重新设置指示器 */ private void resetIndicator() { int childCount = mTabsContainer.getChildCount(); ViewGroup.LayoutParams layoutParams = mIndicator.getLayoutParams(); if (childCount <= 0) { layoutParams.width = 0; } else { layoutParams.width = getWidth() / childCount; } mIndicator.setLayoutParams(layoutParams); // mIndicator.setX(0f); } /** * 设置选项卡 * * @param titles */ public void setTabs(String... titles) { mTabsContainer.removeAllViews(); if (titles != null) { for (int i = 0; i < titles.length; i++) { TextView textView = new TextView(getContext()); textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 22); // textView.setTextColor(mNotSelectedColor); textView.setText(titles[i]); textView.setClickable(true); textView.setPadding(0, 10, 0, 10); textView.setGravity(Gravity.CENTER); textView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 1f)); textView.setTag(i); textView.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { int position = (Integer) v.getTag(); setCurrentTab(position, true); if (listener != null) { listener.onClick(v, position); } } }); mTabsContainer.addView(textView); } // 初始化，默认选中第一个 setCurrentTab(0, false); // 设置指示器 post(new Runnable() { @Override public void run() { // 设置指示器 resetIndicator(); } }); } } /** * 设置当前的tab * * @param position */ public void setCurrentTab(int position, boolean anim) { int childCount = mTabsContainer.getChildCount(); if (position < 0 || position >= childCount) { return; } // 设置每个tab的状态 for (int i = 0; i < childCount; i++) { TextView childView = (TextView) mTabsContainer.getChildAt(i); if (i == position) { childView.setTextColor(mSelectedColor); } else { childView.setTextColor(mNotSelectedColor); } } // 指示器的移动 ObjectAnimator objectAnimator = ObjectAnimator.ofFloat(mIndicator, "x", position * mIndicator.getWidth()); if (anim) { objectAnimator.setDuration(200).start(); } else { objectAnimator.setDuration(0).start(); } } /** * Tabs点击的监听事件 * * @param listener */ public void setOnTabsItemClickListener(OnTabsItemClickListener listener) { this.listener = listener; } public interface OnTabsItemClickListener { public void onClick(View view, int position); } }