Android 仿微信底部菜单栏 + 显示未读消息数量

package com.example.tabtest; import android.graphics.Color; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentTabHost; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.ImageView; import android.widget.TabHost; import android.widget.TextView; import java.util.ArrayList; import java.util.List; public class MainActivity extends AppCompatActivity { public static final int TAB_WECHAT = 0; public static final int TAB_FRIEND = 1; public static final int TAB_CONTACTS = 2; public static final int TAB_SETTING = 3; private List<TabItem> mFragmentList; private FragmentTabHost mFragmentTabHost; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initTabItemData(); } /** * 更新新消息数量 * * @param tabIndex tab 的索引 * @param msgCount 消息数量 */ public void updateMsgCount(int tabIndex, int msgCount) { mFragmentList.get(tabIndex).setNewMsgCount(msgCount); } /** * 初始化 Tab 数据 */ private void initTabItemData() { mFragmentList = new ArrayList<>(); mFragmentList.add(new TabItem( R.drawable.tab_wechat_normal, R.drawable.tab_wechat_selected, "微信", WeChatFragment.class )); mFragmentList.add(new TabItem( R.drawable.tab_friend_normal, R.drawable.tab_friend_selected, "朋友", FriendFragment.class )); mFragmentList.add(new TabItem( R.drawable.tab_contacts_normal, R.drawable.tab_contacts_selected, "联系人", ContactsFragment.class )); mFragmentList.add(new TabItem( R.drawable.tab_settings_normal, R.drawable.tab_settings_selected, "设置", SettingFragment.class )); mFragmentTabHost = (FragmentTabHost) findViewById(android.R.id.tabhost); // 绑定 FragmentManager mFragmentTabHost.setup(this, getSupportFragmentManager(), android.R.id.tabcontent); // 删除分割线 mFragmentTabHost.getTabWidget().setDividerDrawable(null); for (int i = 0; i < mFragmentList.size(); i++) { TabItem tabItem = mFragmentList.get(i); // 创建 tab TabHost.TabSpec tabSpec = mFragmentTabHost.newTabSpec( tabItem.getTabText()). setIndicator(tabItem.getTabView()); // 将创建的 tab 添加到底部 tab 栏中（ @android:id/tabs ） // 将 Fragment 添加到页面中（ @android:id/tabcontent ） mFragmentTabHost.addTab(tabSpec, tabItem.getFragmentClass(), null); // 底部 tab 栏设置背景图片 mFragmentTabHost.getTabWidget().setBackgroundResource(R.drawable.bottom_bar); // 默认选中第一个 tab if (i == 0) { tabItem.setChecked(true); } else { tabItem.setChecked(false); } } // 切换 tab 时，回调此方法 mFragmentTabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() { @Override public void onTabChanged(String tabId) { for (int i = 0; i < mFragmentList.size(); i++) { TabItem tabItem = mFragmentList.get(i); // 通过 tag 检查用户点击的是哪个 tab if (tabId.equals(tabItem.getTabText())) { tabItem.setChecked(true); } else { tabItem.setChecked(false); } } } }); } class TabItem { private ImageView mIvTab; /** * 正常状态的图片 */ private int imageNormal; /** * 选中状态的图片 */ private int imageSelected; private TextView mTvTab; /** * 文字 */ private String tabText; /** * Fragment */ private Class<? extends Fragment> fragmentClass; private View mTabView; /** * 新消息 */ private TextView mTvNewMsg; public TabItem(int imageNormal, int imageSelected, String text, Class<? extends Fragment> fragmentClass) { this.imageNormal = imageNormal; this.imageSelected = imageSelected; this.tabText = text; this.fragmentClass = fragmentClass; } public Class<? extends Fragment> getFragmentClass() { return fragmentClass; } /** * 获取 tab 上的文字 * * @return tab 上的文字 */ public String getTabText() { return tabText; } /** * 设置选中 * * @param checked 是否选中 */ public void setChecked(boolean checked) { if (checked) { mTvTab.setTextColor(getResources().getColor(R.color.colorTabText)); mIvTab.setImageResource(imageSelected); } else { mTvTab.setTextColor(Color.WHITE); mIvTab.setImageResource(imageNormal); } } public View getTabView() { mTabView = View.inflate(MainActivity.this, R.layout.view_tab, null); mIvTab = (ImageView) mTabView.findViewById(R.id.iv_tab); mTvTab = (TextView) mTabView.findViewById(R.id.tv_tab); mTvNewMsg = (TextView) mTabView.findViewById(R.id.tv_new_msg); mIvTab.setImageResource(imageNormal); mTvTab.setText(tabText); return mTabView; } /** * 设置新消息数量 */ public void setNewMsgCount(int count) { if (count > 0) { mTvNewMsg.setText(String.valueOf(count)); } mTvNewMsg.setBackgroundResource(R.drawable.ic_new_msg); } } }