使用Fragment实现Tab切换（高仿微信）

package net.csdn.blog.ruancoder; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentActivity; import android.support.v4.app.FragmentTransaction; import android.view.View; import android.widget.ImageView; import android.widget.TextView; import java.util.ArrayList; import java.util.List; public class MainActivity extends FragmentActivity implements View.OnClickListener { private ImageView mChatImageView; private ImageView mContactsImageView; private ImageView mDiscoverImageView; private ImageView mMineImageView; private TextView mChatTextView; private TextView mContactsTextView; private TextView mDiscoverTextView; private TextView mMineTextView; private List<TabInfo> mTabs = new ArrayList<TabInfo>(); private TabInfo mLastTab; private static final int TAB_INDEX_CHAT = 0; private static final int TAB_INDEX_CONTACTS = 1; private static final int TAB_INDEX_DISCOVER = 2; private static final int TAB_INDEX_MINE = 3; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initView(); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.tab_chat_layout: changePage(TAB_INDEX_CHAT); break; case R.id.tab_contacts_layout: changePage(TAB_INDEX_CONTACTS); break; case R.id.tab_discover_layout: changePage(TAB_INDEX_DISCOVER); break; case R.id.tab_mine_layout: changePage(TAB_INDEX_MINE); break; } } private void changePage(int index) { changeFragment(index); changeTab(index); } private void changeFragment(int index) { FragmentTransaction transaction = getSupportFragmentManager().beginTransaction(); TabInfo tab = mTabs.get(index); if (mLastTab == tab) { return; } if (mLastTab != null) { transaction.hide(mLastTab.fragment);// 隐藏上一次显示的tab页 } if (tab.fragment == null) { tab.fragment = Fragment.instantiate(this, tab.clazz.getName(), tab.args); transaction.add(R.id.main_content, tab.fragment);// 如果当前点击的tab页首次创建，将其添加进来 } else { transaction.show(tab.fragment);// 显示当前点击的tab页 } transaction.commitAllowingStateLoss(); mLastTab = tab; } private void addTab(Class<? extends Fragment> clazz, Bundle args) { TabInfo tabInfo = new TabInfo(clazz, args); mTabs.add(tabInfo); } private class TabInfo { private Fragment fragment; private Class<?> clazz;// Fragment类的class对象 private Bundle args;// 传递参数的Bundle TabInfo(Class<? extends Fragment> clazz, Bundle args) { this.clazz = clazz; this.args = args; } } private void changeTab(int index) { switch (index) { case TAB_INDEX_CHAT: setTabIcon(true, false, false, false); break; case TAB_INDEX_CONTACTS: setTabIcon(false, true, false, false); break; case TAB_INDEX_DISCOVER: setTabIcon(false, false, true, false); break; case TAB_INDEX_MINE: setTabIcon(false, false, false, true); break; } } private void setTabIcon(boolean isChatSelected, boolean isContactsSelected, boolean isDiscoverSelected, boolean isMineSelected) { mChatImageView.setSelected(isChatSelected); mContactsImageView.setSelected(isContactsSelected); mDiscoverImageView.setSelected(isDiscoverSelected); mMineImageView.setSelected(isMineSelected); mChatTextView.setSelected(isChatSelected); mContactsTextView.setSelected(isContactsSelected); mDiscoverTextView.setSelected(isDiscoverSelected); mMineTextView.setSelected(isMineSelected); } private void initView() { mChatImageView = (ImageView) findViewById(R.id.tab_chat_icon); mContactsImageView = (ImageView) findViewById(R.id.tab_contacts_icon); mDiscoverImageView = (ImageView) findViewById(R.id.tab_discover_icon); mMineImageView = (ImageView) findViewById(R.id.tab_mine_icon); mChatTextView = (TextView) findViewById(R.id.tab_chat_text); mContactsTextView = (TextView) findViewById(R.id.tab_contacts_text); mDiscoverTextView = (TextView) findViewById(R.id.tab_discover_text); mMineTextView = (TextView) findViewById(R.id.tab_mine_text); findViewById(R.id.tab_chat_layout).setOnClickListener(this); findViewById(R.id.tab_contacts_layout).setOnClickListener(this); findViewById(R.id.tab_discover_layout).setOnClickListener(this); findViewById(R.id.tab_mine_layout).setOnClickListener(this); // 根据实际需求，可以通过Bundle往Fragment中传递参数 Bundle args = new Bundle(); addTab(ChatFragment.class, args); addTab(ContactsFragment.class, null); addTab(DiscoverFragment.class, null); addTab(MineFragment.class, null); // 默认选择第一个tab changePage(0); } }