Android Fragment Base
public class FragmentTabsActivity extends FragmentActivity implements OnClickListener { //定义FragmentTabHost对象 private SaveFragmentTabHost mTabHost; //定义数组来存放Fragment界面 private final Class[] fragmentArray = { A.class, B.class, C.class, D.class, E.class, F.class, G.class, H.class, I.class }; //定义数组来存放按钮图片 private int mIconFontArray[] = { R.string.A, R.string.B, R.string.C, R.string.D, R.string.E }; private int mIconSelectArray[] = { R.string.AA, R.string.BB, R.string.CC, R.string.DD, R.string.EE}; //Tab选项卡的文字 private long keyNum; private LinearLayout tabsParent; private MenuDialog menuDialog; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initViews(); keyNum = 0; } /** * 在这里获取到每个需要用到的控件的实例，并给它们设置好必要的点击事件。 */ private void initViews() { //实例化布局对象 // 得到fragment的个数 int count = fragmentArray.length; tabsParent = (LinearLayout) findViewById(R.id.tabsParent); //实例化TabHost对象，得到TabHost mTabHost = (SaveFragmentTabHost) findViewById(android.R.id.tabhost); mTabHost.setup(this, getSupportFragmentManager(), R.id.realtabcontent); for (int i = 0; i < count; i++) { // 为每一个Tab按钮设置图标、文字和内容 String name = String.valueOf(i); TabSpec tabSpec = mTabHost.newTabSpec(name).setIndicator(name); //将Tab按钮添加进Tab选项卡中 mTabHost.addTab(tabSpec, fragmentArray[i], null); //设置Tab按钮的背景 mTabHost.getTabWidget().getChildAt(i).setBackgroundResource(R.drawable.selector_tab); }
mytabs = getTabHost();
mytabs.setOnTabChangedListener(new OnTabChangeListener() {
@Override
public void onTabChanged(String arg0) {
Log.i("***Selected Tab", "Im currently in tab with index::" + mytabs.getCurrentTab());
}
});
setupTabsBar(); menuDialog = new MenuDialog(mActivity, mTabHost); } /** * 给Tab按钮设置图标和文字 */ private LinearLayout homeLayout, celebrityLayout, brandLayout, exploreLayout, moreLayout; private TextView homeTv, celebrityTv, brandTv, exploreTv, moreTv; private void setupTabsBar() { homeLayout = (LinearLayout) findViewById(R.id.tabLayoutHome); homeLayout.setSelected(true); celebrityLayout = (LinearLayout) findViewById(R.id.tabLayoutCelebrity); brandLayout = (LinearLayout) findViewById(R.id.tabLayoutBrand); exploreLayout = (LinearLayout) findViewById(R.id.tabLayoutExplore); moreLayout = (LinearLayout) findViewById(R.id.tabLayoutMore); homeLayout.setOnClickListener(this); celebrityLayout.setOnClickListener(this); brandLayout.setOnClickListener(this); exploreLayout.setOnClickListener(this); moreLayout.setOnClickListener(this); homeTv = (TextView) findViewById(R.id.tabIconHome); celebrityTv = (TextView) findViewById(R.id.tabIconCelebrity); brandTv = (TextView) findViewById(R.id.tabIconBrand); exploreTv = (TextView) findViewById(R.id.tabIconExplore); moreTv = (TextView) findViewById(R.id.tabIconMore); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.tabLayoutHome: setCurrentFragment(0); break; case R.id.tabLayoutCelebrity: setCurrentFragment(1); break; case R.id.tabLayoutBrand: setCurrentFragment(2); break; case R.id.tabLayoutExplore: setCurrentFragment(3); break; case R.id.tabLayoutMore: setCurrentFragment(4); menuDialog.home(); break; } } private void setCurrentFragment(int index) { homeLayout.setSelected(index == 0); celebrityLayout.setSelected(index == 1); brandLayout.setSelected(index == 2); exploreLayout.setSelected(index == 3); moreLayout.setSelected(index == 4); homeTv.setText(index == 0 ? getResources().getString(mIconSelectArray[0]) : getResources().getString(mIconFontArray[0])); celebrityTv.setText(index == 1 ? getResources().getString(mIconSelectArray[1]) : getResources().getString(mIconFontArray[1])); brandTv.setText(index == 2 ? getResources().getString(mIconSelectArray[2]) : getResources().getString(mIconFontArray[2])); exploreTv.setText(index == 3 ? getResources().getString(mIconSelectArray[3]) : getResources().getString(mIconFontArray[3])); moreTv.setText(index == 4 ? getResources().getString(mIconSelectArray[4]) : getResources().getString(mIconFontArray[4])); if (index != 4) mTabHost.setCurrentTab(index); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_DOWN) { if ((System.currentTimeMillis() - keyNum) > 2000) { Toast.makeText(mActivity, "再按一次退出", Toast.LENGTH_SHORT).show(); keyNum = System.currentTimeMillis(); } else { imageLoader.stop(); System.exit(0); finish(); android.os.Process.killProcess(android.os.Process.myPid()); } return true; } return super.onKeyDown(keyCode, event); } }
/**BaseActivity**/ public class Activity extends Activity implements OnClickListener { /**tag 用于测试log用 **/ public String tag = this.getClass().getSimpleName(); /**Activity**/ protected Activity mActivity; /**loading**/ protected Dialog progressDialog; /** 实例化ImageLoader**/ protected ImageLoader imageLoader; /**显示图片设置**/ protected DisplayImageOptions options; /**用户Token**/ public String userToken; public ObjectMapper mapper = new ObjectMapper(); /**翻页相关**/ public int start = 1; public int refreshCnt = 1; public int dataStatus; public static final int DONE = 0; public static final int INITDATA = 1; public static final int REFRESH = 2; public static final int LOADDATA = 3; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Log.e(tag, "onCreate------"); mActivity = DFActivity.this; progressDialog = DialogUtil.createLoadingDialog(mActivity, R.string.load_data_content); imageLoader = ImageLoader.getInstance(); options = new AppUtils().getOptions(); userToken = SharedUtil.getInstance(mActivity).getString(AppConstants.JSON_USER_TOKEN); } /** * 按钮注册和监听事件注册 * 注册IconFont字体 */ /** * @param title */ public void initActionBar(String title) { TextView actionTitle = (TextView) findViewById(R.id.actionTitle); actionTitle.setText(title); Button btnBack = (Button) findViewById(R.id.actionBack); AppUtils.iconFont(mActivity, btnBack, 30, 0); btnBack.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { mActivity.finish(); } }); Button btnMenu = (Button) findViewById(R.id.actionMenu); AppUtils.iconFont(mActivity, btnMenu, 30, 0); btnMenu.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // mActivity.finish(); } }); } @Override public void onClick(View v) { } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == KeyEvent.ACTION_DOWN) { this.finish(); } return super.onKeyDown(keyCode, event); } public void initFollow() { // followed = mActivity.getString(R.string.btnFollowed); // addFollow = mActivity.getString(R.string.btnAddFollow); } public void showLog(Object log) { Log.e(tag, log.toString()); } /** * Toast.makeText * * @param mContext * @param string */ public void showToast(Object... string) { Toast.makeText(mActivity, String.valueOf(string.toString()), Toast.LENGTH_SHORT).show(); } public void goAct(Class<?> cls, Boolean finish) { Intent intent = new Intent(mActivity, cls); startActivity(intent); if (finish) { this.finish(); } } @Override public void onStart() { super.onStart(); Log.e(tag, "onStart------"); } @Override public void onResume() { super.onResume(); Log.e(tag, "onResume------"); } @Override public void onPause() { super.onPause(); Log.e(tag, "onPause------"); } @Override public void onStop() { super.onStop(); Log.e(tag, "onStop------"); } @Override public void onDestroy() { super.onDestroy(); Log.e(tag, "onDestroy------"); } }
xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".FragmentTabsActivity" > <FrameLayout android:id="@+id/realtabcontent" android:layout_width="match_parent" android:layout_height="0dip" android:layout_weight="1" /> <SaveFragmentTabHost android:id="@android:id/tabhost" android:layout_width="match_parent" android:layout_height="wrap_content" android:visibility="gone" > <FrameLayout android:id="@android:id/tabcontent" android:layout_width="0dp" android:layout_height="0dp" android:layout_weight="0" /> </SaveFragmentTabHost> <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="53dp" android:background="@android:color/black" android:baselineAligned="false" tools:context=".FragmentTabsActivity" > <LinearLayout android:id="@+id/tabLayoutHome" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconHome" style="@style/tab_top_style" android:text="@string/fontHomeSelect" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringHome" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutCelebrity" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconCelebrity" style="@style/tab_top_style" android:text="@string/fontCelebrity" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringCelebrity" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutBrand" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconBrand" style="@style/tab_top_style" android:text="@string/fontBrand" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringBrand" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutExplore" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconExplore" style="@style/tab_top_style" android:text="@string/fontExplore" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringExplore" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutMore" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconMore" style="@style/tab_top_style" android:text="@string/fontMore" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringMore" > </TextView> </LinearLayout> </LinearLayout><?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="53dp" android:background="@android:color/black" android:baselineAligned="false" tools:context=".FragmentTabsActivity" > <LinearLayout android:id="@+id/tabLayoutHome" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconHome" style="@style/tab_top_style" android:text="@string/fontHomeSelect" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringHome" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutCelebrity" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconCelebrity" style="@style/tab_top_style" android:text="@string/fontCelebrity" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringCelebrity" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutBrand" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconBrand" style="@style/tab_top_style" android:text="@string/fontBrand" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringBrand" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutExplore" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconExplore" style="@style/tab_top_style" android:text="@string/fontExplore" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringExplore" > </TextView> </LinearLayout> <LinearLayout android:id="@+id/tabLayoutMore" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="1.0" android:background="@drawable/button_actionbar_menu" android:gravity="center" android:orientation="vertical" > <TextView android:id="@+id/tabIconMore" style="@style/tab_top_style" android:text="@string/fontMore" > </TextView> <TextView style="@style/tab_bottom_style" android:text="@string/stringMore" > </TextView> </LinearLayout> </LinearLayout> </LinearLayout>
SaveFragmentTabHost
/* * Copyright (C) 2012 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * Special TabHost that allows the use of {@link Fragment} objects for its tab * content. When placing this in a view hierarchy, after inflating the hierarchy * you must call {@link #setup(Context, FragmentManager, int)} to complete the * initialization of the tab host. * * <p> * Here is a simple example of using a FragmentTabHost in an Activity: * * {@sample * development/samples/Support4Demos/src/com/example/android/supportv4/app/ * FragmentTabs.java complete} * * <p> * This can also be used inside of a fragment through fragment nesting: * * {@sample * development/samples/Support4Demos/src/com/example/android/supportv4/app/ * FragmentTabsFragmentSupport.java complete} */ public class SaveFragmentTabHost extends TabHost implements TabHost.OnTabChangeListener { private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>(); private FrameLayout mRealTabContent; private Context mContext; private FragmentManager mFragmentManager; private int mContainerId; private TabHost.OnTabChangeListener mOnTabChangeListener; private TabInfo mLastTab; private boolean mAttached; static final class TabInfo { private final String tag; private final Class<?> clss; private final Bundle args; private Fragment fragment; TabInfo(String _tag, Class<?> _class, Bundle _args) { tag = _tag; clss = _class; args = _args; } } static class DummyTabFactory implements TabHost.TabContentFactory { private final Context mContext; public DummyTabFactory(Context context) { mContext = context; } @Override public View createTabContent(String tag) { View v = new View(mContext); v.setMinimumWidth(0); v.setMinimumHeight(0); return v; } } static class SavedState extends BaseSavedState { String curTab; SavedState(Parcelable superState) { super(superState); } private SavedState(Parcel in) { super(in); curTab = in.readString(); } @Override public void writeToParcel(Parcel out, int flags) { super.writeToParcel(out, flags); out.writeString(curTab); } @Override public String toString() { return "FragmentTabHost.SavedState{" + Integer.toHexString(System.identityHashCode(this)) + " curTab=" + curTab + "}"; } public static final Parcelable.Creator<SavedState> CREATOR = new Parcelable.Creator<SavedState>() { public SavedState createFromParcel(Parcel in) { return new SavedState(in); } public SavedState[] newArray(int size) { return new SavedState[size]; } }; } public SaveFragmentTabHost(Context context) { // Note that we call through to the version that takes an AttributeSet, // because the simple Context construct can result in a broken object! super(context, null); initFragmentTabHost(context, null); } public SaveFragmentTabHost(Context context, AttributeSet attrs) { super(context, attrs); initFragmentTabHost(context, attrs); } private void initFragmentTabHost(Context context, AttributeSet attrs) { TypedArray a = context.obtainStyledAttributes(attrs, new int[] { android.R.attr.inflatedId }, 0, 0); mContainerId = a.getResourceId(0, 0); a.recycle(); super.setOnTabChangedListener(this); } private void ensureHierarchy(Context context) { // If owner hasn't made its own view hierarchy, then as a convenience // we will construct a standard one here. if (findViewById(android.R.id.tabs) == null) { LinearLayout ll = new LinearLayout(context); ll.setOrientation(LinearLayout.VERTICAL); addView(ll, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); TabWidget tw = new TabWidget(context); tw.setId(android.R.id.tabs); tw.setOrientation(TabWidget.HORIZONTAL); ll.addView(tw, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT, 0)); FrameLayout fl = new FrameLayout(context); fl.setId(android.R.id.tabcontent); ll.addView(fl, new LinearLayout.LayoutParams(0, 0, 0)); mRealTabContent = fl = new FrameLayout(context); mRealTabContent.setId(mContainerId); ll.addView(fl, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, 0, 1)); } } /** * @deprecated Don't call the original TabHost setup, you must instead call * {@link #setup(Context, FragmentManager)} or * {@link #setup(Context, FragmentManager, int)}. */ @Override @Deprecated public void setup() { throw new IllegalStateException("Must call setup() that takes a Context and FragmentManager"); } public void setup(Context context, FragmentManager manager) { ensureHierarchy(context); // Ensure views required by super.setup() super.setup(); mContext = context; mFragmentManager = manager; ensureContent(); } public void setup(Context context, FragmentManager manager, int containerId) { ensureHierarchy(context); // Ensure views required by super.setup() super.setup(); mContext = context; mFragmentManager = manager; mContainerId = containerId; ensureContent(); mRealTabContent.setId(containerId); // We must have an ID to be able to save/restore our state. If // the owner hasn't set one at this point, we will set it ourself. if (getId() == View.NO_ID) { setId(android.R.id.tabhost); } } private void ensureContent() { if (mRealTabContent == null) { mRealTabContent = (FrameLayout) findViewById(mContainerId); if (mRealTabContent == null) { throw new IllegalStateException("No tab content FrameLayout found for id " + mContainerId); } } } @Override public void setOnTabChangedListener(OnTabChangeListener l) { mOnTabChangeListener = l; } public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) { tabSpec.setContent(new DummyTabFactory(mContext)); String tag = tabSpec.getTag(); TabInfo info = new TabInfo(tag, clss, args); if (mAttached) { // If we are already attached to the window, then check to make // sure this tab's fragment is inactive if it exists. This shouldn't // normally happen. info.fragment = mFragmentManager.findFragmentByTag(tag); if (info.fragment != null && !info.fragment.isDetached()) { FragmentTransaction ft = mFragmentManager.beginTransaction(); // ft.detach(info.fragment); ft.hide(info.fragment); ft.commit(); } } mTabs.add(info); addTab(tabSpec); } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); String currentTab = getCurrentTabTag(); // Go through all tabs and make sure their fragments match // the correct state. FragmentTransaction ft = null; for (int i = 0; i < mTabs.size(); i++) { TabInfo tab = mTabs.get(i); tab.fragment = mFragmentManager.findFragmentByTag(tab.tag); // if (tab.fragment != null && !tab.fragment.isDetached()) { if (tab.fragment != null) { if (tab.tag.equals(currentTab)) { // The fragment for this tab is already there and // active, and it is what we really want to have // as the current tab. Nothing to do. mLastTab = tab; } else { // This fragment was restored in the active state, // but is not the current tab. Deactivate it. if (ft == null) { ft = mFragmentManager.beginTransaction(); } // ft.detach(tab.fragment); ft.hide(tab.fragment); } } } // We are now ready to go. Make sure we are switched to the // correct tab. mAttached = true; ft = doTabChanged(currentTab, ft); if (ft != null) { ft.commit(); mFragmentManager.executePendingTransactions(); } } @Override protected void onDetachedFromWindow() { super.onDetachedFromWindow(); mAttached = false; } @Override protected Parcelable onSaveInstanceState() { Parcelable superState = super.onSaveInstanceState(); SavedState ss = new SavedState(superState); ss.curTab = getCurrentTabTag(); return ss; } @Override protected void onRestoreInstanceState(Parcelable state) { SavedState ss = (SavedState) state; super.onRestoreInstanceState(ss.getSuperState()); setCurrentTabByTag(ss.curTab); } @Override public void onTabChanged(String tabId) { if (mAttached) { FragmentTransaction ft = doTabChanged(tabId, null); if (ft != null) { ft.commit(); } } if (mOnTabChangeListener != null) { mOnTabChangeListener.onTabChanged(tabId); } } private FragmentTransaction doTabChanged(String tabId, FragmentTransaction ft) { TabInfo newTab = null; for (int i = 0; i < mTabs.size(); i++) { TabInfo tab = mTabs.get(i); if (tab.tag.equals(tabId)) { newTab = tab; } } if (newTab == null) { throw new IllegalStateException("No tab known for tag " + tabId); } if (mLastTab != newTab) { if (ft == null) { ft = mFragmentManager.beginTransaction(); } if (mLastTab != null) { if (mLastTab.fragment != null) { // ft.detach(mLastTab.fragment); ft.hide(mLastTab.fragment); } } if (newTab != null) { if (newTab.fragment == null) { newTab.fragment = Fragment.instantiate(mContext, newTab.clss.getName(), newTab.args); ft.add(mContainerId, newTab.fragment, newTab.tag); } else { // ft.attach(newTab.fragment); ft.show(newTab.fragment); } } mLastTab = newTab; } return ft; } }
or,Fragment deal
使用FragmentTabHost时，Fragment之间切换时每次都会调用onCreateView方法，导致每次Fragment的布局都重绘，无法保持Fragment原有状态。
解决办法：在Fragment onCreateView方法中缓存View
private View rootView;//缓存Fragment view @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { if(rootView==null){ rootView=inflater.inflate(R.layout.tab_fragment, null); } //缓存的rootView需要判断是否已经被加过parent， 如果有parent需要从parent删除，要不然会发生这个rootview已经有parent的错误。 ViewGroup parent = (ViewGroup) rootView.getParent(); if (parent != null) { parent.removeView(rootView); } return rootView; }