android-Improvement << Imitation qq>> frame source

The article is mainly modified in csdn a great god of an article, I think this article is very thorough object-oriented, below to share the following points to learn:

Android app one of the classic main interface framework: Imitation QQ (using fragment, with source code)

1. Calculate and optimize by & symbol: ( later by asking colleagues, said that the computer through the bit operation efficiency than usual switch efficiency, and explained the principle of the algorithm. )

public class Constant {public static final int sign_fragment_message=0x01 <<1;public static final int Sign_fragment_ contacts=0x01 <<2;public static final int sign_fragment_news=0x01 <<3;public static final int Sign_fragment_ SETTENGS=0X01 <<4;}

@Overridepublic void onclickcallback (int itemID) {String tag = ""; if (ItemID & constant.sign_fragment_message)! = 0) {tag = constant.str_fragment_message;} else if ((ItemID & constant.sign_fragment_contacts)! = 0) {tag = constant.str_fragment_contacts;} else if (ItemID &am P constant.sign_fragment_news)! = 0) {tag = constant.str_fragment_news;} else if (ItemID & Constant.sign_fragment_ settengs)! = 0) {tag = constant.str_fragment_settings;} Mheaderpanellayout.settext (tag); settabsection (tag);}

2. "Dynamic" adjustment of buttons in the middle of the bottom bar via onlayout

@Overrideprotected void OnLayout (Boolean changed, int l, int t, int r, int b) {super.onlayout (changed, L, T, R, b); Layouti TEM (L, T, R, b);} private void Layoutitem (int left, int top, int right, int bottom) {int allchildwidth=0;int num=getchildcount (); for (int i = 0; i < num; i++) {Allchildwidth+=getchildat (i). GetWidth ();} int Absolutewidth=right-left-getpaddingleft ()-getpaddingright (), int blankwidth= (absolutewidth-allchildwidth)/( NUM-1)///Set 2nd 3 button spacing Layoutparams params1= (layoutparams) mcontactsbtn.getlayoutparams ();p arams1.leftmargin= Blankwidth;mcontactsbtn.setlayoutparams (PARAMS1); Layoutparams params2= (Layoutparams) mnewsbtn.getlayoutparams ();p arams2.leftmargin=blankwidth; Mnewsbtn.setlayoutparams (PARAMS2);}

3. Two instances of the application of the layout:

1) through Layoutinflater.

Public Imagetext (context context, AttributeSet Attrs) {Super (context, attrs); Layoutinflater.from (context). Inflate (R.layout.image_text_layout, this,true); mimageview= (ImageView) Findviewbyid ( R.id.iv_imgae_text); mtextiew= (TextView) Findviewbyid (r.id.tv_imgae_text);}

2) through Onfinishinflater ()

<?xml version= "1.0" encoding= "Utf-8"? ><org.lean.ui.bottompanellayout xmlns:android= "/http Schemas.android.com/apk/res/android "android:layout_width=" match_parent "android:layout_height=" Wrap_content "and Roid:background= "#FFF3F3F3" android:paddingleft= "20DP" android:paddingright= "20DP" Android:layout_alignparentbott Om= "true" > <org.lean.ui.imagetext android:id= "@+id/message_btn" android:layout_width= "wrap_content "Android:layout_height=" Wrap_content "android:layout_alignparentleft=" true "/> <org.lean.ui.imaget Ext android:id= "@+id/contacts_btn" android:layout_width= "wrap_content" android:layout_height= "Wrap_co Ntent "android:layout_torightof=" @id/message_btn "/> <org.lean.ui.imagetext android:id=" @+id/news_b TN "android:layout_width=" wrap_content "android:layout_height=" Wrap_content "Android:layout_torightof = "@id/contacts_btn"/> <org.lean.uI.imagetext android:id= "@+id/settings_btn" android:layout_width= "Wrap_content" android:layout_height= "Wrap_content" android:layout_alignparentright= "true"/></org.lean.ui.bottompanellayout>

@Overrideprotected void Onfinishinflate () {super.onfinishinflate (); mmessagebtn= (Imagetext) Findviewbyid ( R.ID.MESSAGE_BTN); mcontactsbtn= (Imagetext) Findviewbyid (R.ID.CONTACTS_BTN); mnewsbtn= (ImageText) findViewById ( R.ID.NEWS_BTN); msettingsbtn= (Imagetext) Findviewbyid (R.ID.SETTINGS_BTN); Initclickevent ();}

4. Proxy for data transfer (one of the most common design patterns in iOS)

public class Bottompanellayout extends Relativelayout implements Onclicklistener{private bottompanelcallbackprotocal mcallbackprotocal;//Proxy Protocol public void setcallbackprotocal (Bottompanelcallbackprotocal callbackprotocal) { this.mcallbackprotocal = callbackprotocal;} public interface bottompanelcallbackprotocal{public void Onclickcallback (int itemID); /** * 1. Modify the style itself * 2. External Declaration event */@Overridepublic void OnClick (View v) {initbottompanel (); int Index=-1;switch (V.getid ()) {CA Se r.id.message_btn:index=constant.sign_fragment_message;mmessagebtn.setchecked (index); Break;case R.id.contacts_ btn:index=constant.sign_fragment_contacts;mcontactsbtn.setchecked (index); Break;case R.id.news_btn:index= constant.sign_fragment_news;mnewsbtn.setchecked (index); Break;case R.id.settings_btn:index=constant.sign_ fragment_settengs;msettingsbtn.setchecked (index); break;default:break;} if (mcallbackprotocal!=null) {mcallbackprotocal.onclickcallback (index);}}}

public class Mainactivity extends Activity implementsbottompanelcallbackprotocal {@Overridepublic void Onclickcallback (int ItemID) {String tag = ""; if ((ItemID & constant.sign_fragment_message)! = 0) {tag = constant.str_fragment_message;} else if ((ItemID & constant.sign_fragment_contacts)! = 0) {tag = constant.str_fragment_contacts;} else if (ItemID &am P constant.sign_fragment_news)! = 0) {tag = constant.str_fragment_news;} else if (ItemID & Constant.sign_fragment_ settengs)! = 0) {tag = constant.str_fragment_settings;} Mheaderpanellayout.settext (tag); settabsection (tag);}}

5. Modify the original fragment jump code(The previous method Ensuretransaction () is to be judged at the time of pasting or elimination, but as a transaction, it is only necessary to make sure that the thing is only one start, without having to call it every time)

private void Settabsection (String tag) {if (Textutils.equals (tag, currfagtag)) {return;} Ensuretransaction (); if (Currfagtag! = null &&!currfagtag.equals ("")) {detachfragment (Getfragment (Currfagtag ));} Attachfragment (R.id.fragment_panel, getfragment (tag), tag); CommitTransaction ();}

private void Ensuretransaction () {if (mfragmenttransaction = = null) {mfragmenttransaction = Mfragmentmanager.begintransaction (); Mfragmenttransaction.settransition (Fragmenttransaction.transit_fragment_ FADE);}}

6.Fragment fragment to jump and pass the value of the improvement. (here the experiment from Messagefragment click TextView Jump to contactfragment);

1> in the messagefragment.

@Overridepublic void onactivitycreated (Bundle savedinstancestate) {super.onactivitycreated (savedinstancestate); Getactivity (). Findviewbyid (R.ID.MSG_TV). Setonclicklistener (New Onclicklistener () {@Overridepublic void OnClick ( View v) {((mainactivity) getactivity ()). Settabsection (constant.str_fragment_contacts);}});

2> inin ContactfragmentDeclaring data proxies

Declares a variable that stores all the parameters required by the fragment to manually invoke its update data when the view is refreshed private contactfragmentcallback mcontactfragmentcallback;// Declares that the interface public interface contactfragmentcallback{//describes the fragment update requires a String object public string Getcontentstr ();}

3>messagefragment Implement the agent

public class Messagefragment extends Basefragment implements contactfragmentcallback{@Overridepublic String Getcontentstr () {return "ABC";}}

4> inin ContactfragmentCallback

@Overridepublic void Onresume () {super.onresume (); mainactivity.currfagtag=constant.str_fragment_contacts;//by removing the data stored in the last FRAGMENT FRAGMENT f= ((mainactivity) Getactivity ()). Getfragment (Constant.str_fragment_message); if (F!=null&&f instanceof Contactfragmentcallback) {mcontactfragmentcallback= (contactfragmentcallback) F; TextView textview= (TextView) ((mainactivity) getactivity ()). Findviewbyid (R.ID.CONTACT_TV); Textview.settext ( Mcontactfragmentcallback.getcontentstr ());}}