android-改善<<仿QQ>>框架源码

该文章主要修改于CSDN某大神的一篇文章,本人觉得这篇文章的面向对象很透彻,下面分享如下可学习的几点:

Android应用经典主界面框架之一:仿QQ (使用Fragment, 附源码)

1.通过&符号实现计算优化:（后来通过问同事，说是计算机通过位运算 效率比平时的switch效率高,并讲解了该算法的原理。）

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;	}

@Override	public 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 & 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.通过onLayout对底部栏中间的按钮进行“动态”调整

@Override	protected void onLayout(boolean changed, int l, int t, int r, int b) {		super.onLayout(changed, l, t, r, b);		layoutItem(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);		//设置第2 3个按钮的间距		LayoutParams params1=(LayoutParams) mContactsBtn.getLayoutParams();		params1.leftMargin=blankWidth;		mContactsBtn.setLayoutParams(params1);		LayoutParams params2=(LayoutParams) mNewsBtn.getLayoutParams();		params2.leftMargin=blankWidth;		mNewsBtn.setLayoutParams(params2);	}

1）通过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）通过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"    android:background="#FFF3F3F3"    android:paddingLeft="20dp"    android:paddingRight="20dp"    android:layout_alignParentBottom="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.ImageText        android:id="@+id/contacts_btn"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_toRightOf="@id/message_btn" />    <org.lean.ui.ImageText        android:id="@+id/news_btn"        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>

@Override	protected 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.代理实现数据传递（IOS中最常用的一种设计模式）

public class BottomPanelLayout extends RelativeLayout implements OnClickListener{		private BottomPanelCallBackProtocal mCallBackProtocal;		//代理协议	public void setCallBackProtocal(BottomPanelCallBackProtocal callBackProtocal) {		this.mCallBackProtocal = callBackProtocal;	}		public interface BottomPanelCallBackProtocal{		public void onClickCallBack(int itemID);	}	/**  	 * 1.修改本身样式 	 * 2.对外声明事件	 */	@Override	public void onClick(View v) {		initBottomPanel();		int index=-1;		switch (v.getId()) {			case 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 implements		BottomPanelCallBackProtocal {	@Override	public 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 & 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);	}}

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);		}	}

1>在MessageFragment 中

	@Override	public void onActivityCreated(Bundle savedInstanceState) {		super.onActivityCreated(savedInstanceState);		getActivity().findViewById(R.id.msg_tv).setOnClickListener(new OnClickListener() {						@Override			public void onClick(View v) {				((MainActivity)getActivity()).setTabSection(Constant.STR_FRAGMENT_CONTACTS);			}		});	}

	//声明一个变量,该变量存储该Fragment所需要的一切参数 当刷新View时手动调用其更新数据	private ContactFragmentCallBack mContactFragmentCallBack;		//声明该接口	public interface ContactFragmentCallBack{		//说明该Fragment更新时需要一个String对象		public String getContentStr();	}

public class MessageFragment extends BaseFragment implements ContactFragmentCallBack{	@Override	public String getContentStr() {		return "abc";	}}

	@Override	public void onResume() {		super.onResume();		MainActivity.currFagTag=Constant.STR_FRAGMENT_CONTACTS;				//通过取出 存储于上个Fragment中的数据		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());		}	}