Builder设计模式构建NavigationBar

首先定义布局:顶部的布局，一般分为左边返回键按钮，中间是title，右边是文本

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="@style/title_bar_style">

<TextView
android:id="@+id/back"
style="@style/back_view" />

<TextView
android:id="@+id/title"
style="@style/title_text_style"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:layout_marginLeft="75.0dip"
android:layout_marginRight="75.0dip"
android:ellipsize="end"
android:singleLine="true"
android:visibility="gone"
/>

<TextView
android:id="@+id/right_text"
android:visibility="gone"
style="@style/title_bar_button"
android:layout_alignParentRight="true" />
</RelativeLayout>

<style name="title_bar_style">
<item name="android:background">@color/title_bar_bg_day</item>
<item name="android:paddingLeft">0.0dip</item>
<item name="android:paddingRight">0.0dip</item>
<item name="android:layout_width">fill_parent</item>
<item name="android:layout_height">44.0dip</item>
</style>
<color name="title_bar_bg_day">#ffdcd9cf</color>

<style name="back_view" parent="@style/title_bar_button">
<item name="android:gravity">center</item>
<item name="android:background">@drawable/btn_back</item>
<item name="android:paddingLeft">0.0dip</item>
<item name="android:paddingRight">0.0dip</item>
<item name="android:layout_marginLeft">0.0dip</item>
<item name="android:layout_marginRight">0.0dip</item>
<item name="android:text">@null</item>
<item name="android:drawableLeft">@null</item>
</style>

<style name="title_text_style">
<item name="android:textSize">18.0sp</item>
<item name="android:textColor">@color/s9</item>
</style>
<color name="s9">#ff6b5547</color>

<style name="title_bar_button">
<item name="android:textSize">16.0sp</item>
<item name="android:textColor">@color/s9</item>
<item name="android:gravity">center</item>
<item name="android:background">@null</item>
<item name="android:paddingLeft">5.0dip</item>
<item name="android:paddingRight">5.0dip</item>
<item name="android:layout_width">wrap_content</item>
<item name="android:layout_height">fill_parent</item>
<item name="android:layout_marginLeft">0.0dip</item>
<item name="android:layout_marginRight">10.0dip</item>
</style>
<color name="s9">#ff6b5547</color>

首先定义一个接口：定义导航条的规范，有个布局的id和设置参数

public interface INavigationBar {
/**
* 头部的布局
*/

public int bindLayoutld();

/**
* 绑定头部的参数
*/
public void applyview();
}

定义一个基本的导航条类

public abstract class AbsNavigationBar<P extends AbsNavigationBar.Builder.AbsNavigationParams> implements INavigationBar {
private P mParams;
private View mNagivationView;

public AbsNavigationBar(P params) {
this.mParams = params;
createAndBindView();
}

public P getParams() {
return mParams;
}

/**
* 创建和绑定view
*/
private void createAndBindView() {
if(mParams.mParent==null){
ViewGroup viewGroup = (ViewGroup) ((Activity) mParams.mContext)
.findViewById(android.R.id.content);
mParams.mParent = (ViewGroup) viewGroup.getChildAt(0);
}
if(mParams.mParent==null){
return;
}
//1.创建View
mNagivationView = LayoutInflater.from(mParams.mContext).inflate(bindLayoutld(), mParams.mParent, false);
//2.添加
mParams.mParent.addView(mNagivationView, 0);
//3.放置参数
applyview();
}

//AbsNavigationBar  Builder  参数params
public abstract static class Builder {
AbsNavigationParams P;

public Builder(Context context, ViewGroup parent) {//目标parent
P = new AbsNavigationParams(context, parent);
}

//放置参数
public static class AbsNavigationParams {
public Context mContext;
public ViewGroup mParent;

public AbsNavigationParams(Context context, ViewGroup parent) {
this.mContext = context;
this.mParent = parent;
}
}
//由子类去实现builder
public abstract AbsNavigationBar builder();
}
/**
* 设置文本
*
* @param viewId id
* @param text   设置的内容
*/
public void setText(int viewId, String text) {
TextView tv = findviewById(viewId);
tv.setVisibility(View.VISIBLE);
if (!TextUtils.isEmpty(text)) {
tv.setText(text);
}
}

/**
* 设置点击事件
* @param viewId  控件的id
* @param listener  事件
*/
public void setOnClickListener(int viewId, View.OnClickListener listener) {
findviewById(viewId).setOnClickListener(listener);
}

public void setIcon(int viewId, int icon) {
findviewById(viewId).setBackgroundResource(icon);
}
/**
* 减少findview的次数
*/
private <T extends View> T findviewById(int viewId) {
return (T) mNagivationView.findViewById(viewId);
}

}

默认的导航条

public class DefaultNavigationBar extends AbsNavigationBar<DefaultNavigationBar.Builder.DefaultNavigationParams> {
public DefaultNavigationBar(DefaultNavigationBar.Builder.DefaultNavigationParams params) {
super(params);
}

@Override
public int bindLayoutld() {
return R.layout.title_bar;
}

@Override
public void applyview() {
//绑定效果
setText(R.id.title, getParams().mTitle);
setText(R.id.right_text, getParams().mRightText);
setOnClickListener(R.id.right_text, getParams().mRightOnClickListener);
setOnClickListener(R.id.back, getParams().mLeftOnClickListener);
setIcon(R.id.right_text, getParams().mRightIcon);
}

public static class Builder extends AbsNavigationBar.Builder {
DefaultNavigationParams P;

public Builder(Context context, ViewGroup parent) {
super(context, parent);
P = new DefaultNavigationParams(context, parent);
}

//1.设置所有效果
//设置标题
public DefaultNavigationBar.Builder setTitle(String title) {
P.mTitle = title;
return this;
}

//设置右边文字
public DefaultNavigationBar.Builder setRightText(String rightText) {
P.mRightText = rightText;
return this;
}

//设置右边图标
public DefaultNavigationBar.Builder setRightIcon(int rightIcon) {
P.mRightIcon = rightIcon;
return this;
}

//设置右边点击事件
public DefaultNavigationBar.Builder setRightOnClickListener(View.OnClickListener rightOnClickListener) {
P.mRightOnClickListener = rightOnClickListener;
return this;
}

//设置左边文字
public DefaultNavigationBar.Builder setLeftText(String leftText) {
P.mLeftText = leftText;
return this;
}

//设置左边图标
public DefaultNavigationBar.Builder setLeftIcon(int leftIcon) {
P.mLeftIcon = leftIcon;
return this;
}

//设置左边点击事件
public DefaultNavigationBar.Builder setLeftOnClickListener(View.OnClickListener leftOnClickListener) {
P.mLeftOnClickListener = leftOnClickListener;
return this;
}

@Override
public DefaultNavigationBar builder() {
DefaultNavigationBar navigationBar = new DefaultNavigationBar(P);
return navigationBar;
}

public static class DefaultNavigationParams extends AbsNavigationParams {
public String mTitle;//设置标题
public String mRightText;//右边文字标题
public int mRightIcon;//右边图片
public View.OnClickListener mRightOnClickListener;//设置右边点击事件
public String mLeftText;//左边文字标题
public int mLeftIcon;//左边图标
public View.OnClickListener mLeftOnClickListener = new View.OnClickListener() {//默认退出程序
@Override
public void onClick(View v) {
((Activity) mContext).finish();
}
};//左边点击事件

//2.放置所有效果
public DefaultNavigationParams(Context context, ViewGroup parent) {
super(context, parent);
}
}
}
}

简单使用

DefaultNavigationBar navigationBar=new DefaultNavigationBar.Builder
//                (this, (ViewGroup) findViewById(R.id.view_group))

(this,null)
//                .setRightIcon(R.drawable.account_icon_weibo)
.setRightText("发布")
.setTitle("投稿")
.setRightOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, "发布", Toast.LENGTH_SHORT).show();
}
})
.builder();