ButterKnife

ButterKnife的使用

11/12/2017 11:21:52 PM

前言

源码地址:ButterKnifeDemo

这是一种依赖注入框架,当然是为了我们更好的便捷开发,当然这只是一个控件级别的注入框架,需要对象类型的话请使用Dagger2,这是jackWharton Google大神写的软件,在使用的过程中我们还能学学人家是怎么样写代码的(Adapter里的ViewHolder绑定问题).代码将更加的清晰可读性更好.

一.使用其中的一些技巧

建立build,相应的版本请参见github:

dependencies {    testCompile 'junit:junit:4.12'    annotationProcessor 'com.jakewharton:butterknife-compiler:8.8.1'}

1.1 配合插件使用

Android ButterKnife Zelezny,安装之后重启即可,使用方法,在layout文件上:Fn + alt + Insert –> Generate –> Generate ButterKnife Injections,可选择性的生成,可更改名称

1.2 每一个新建的moudle中都自动有ButterKnife

在AndroidStudio\plugins\android\lib\templates\gradle-projects\NewAndroidModule\recipe.xml.ftl中添加如下代码,以后新创建的工程默认会添加Butterknife依赖:

<dependency mavenUrl="com.jakewharton:butterknife:7.0.1" />

二.Activity,Fragment,Adapter三大块中的使用

2.1 Activity

这个使用比较简单了,直接贴代码即可:

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="com.u9time.butterknife.MainActivity">    <LinearLayout        android:id="@+id/ll"        android:layout_width="match_parent"        android:layout_height="50dp">        <Button            android:id="@+id/btn_1"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="btn_1" />        <Button            android:id="@+id/btn_2"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="btn_2" />        <Button            android:id="@+id/btn_3"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="btn_3" />        <Button            android:id="@+id/btn_4"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="btn_4" />    </LinearLayout>    <android.support.v4.view.ViewPager        android:id="@+id/vp"        android:layout_width="match_parent"        android:layout_height="match_parent" /></LinearLayout>

Activity

package com.u9time.butterknife;import android.os.Bundle;import android.support.v4.app.Fragment;import android.support.v4.view.ViewPager;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;import android.widget.LinearLayout;import java.util.ArrayList;import butterknife.BindArray;import butterknife.BindString;import butterknife.BindView;import butterknife.ButterKnife;import butterknife.OnClick;public class MainActivity extends AppCompatActivity {    @BindView(R.id.btn_1)    Button btn1;    @BindView(R.id.btn_2)    Button btn2;    @BindView(R.id.btn_3)    Button btn3;    @BindView(R.id.btn_4)    Button btn4;    @BindView(R.id.ll)    LinearLayout ll;    @BindView(R.id.vp)    ViewPager vp;    /**     * 有很多的额绑定,可以是字符串,数组,颜色,图片等等.     */    @BindString(R.string.hello_blank_fragment)    String hello_blank_fragment;    @BindArray(R.array.city)    String[] city;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ButterKnife.bind(this);        initView();    }    private void initView() {        ArrayList<Fragment> fragmentArrayList = new ArrayList<>();        for (int i = 0; i < 3; i++) {            fragmentArrayList.add(new BlankFragment());        }        vp.setAdapter(new VpAdapter(getSupportFragmentManager(), fragmentArrayList));    }    @OnClick({R.id.btn_1, R.id.btn_2, R.id.btn_3, R.id.btn_4, R.id.ll})    public void onViewClicked(View view) {        switch (view.getId()) {            case R.id.btn_1:                break;            case R.id.btn_2:                break;            case R.id.btn_3:                break;            case R.id.btn_4:                break;            case R.id.ll:                break;        }    }}

2.2 Fragment

其中需要注意是

ButterKnife.bind(this, view)

代码XMl:

<FrameLayout 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"tools:context="com.u9time.butterknife.BlankFragment">    <ListView        android:id="@+id/listview"        android:layout_width="match_parent"        android:layout_height="match_parent" /></FrameLayout>

Fragment:

package com.u9time.butterknife;import android.os.Bundle;import android.support.annotation.Nullable;import android.support.v4.app.Fragment;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ListView;import butterknife.BindView;import butterknife.ButterKnife;import butterknife.Unbinder;public class BlankFragment extends Fragment {    @BindView(R.id.listview)    ListView listview;    Unbinder unbinder;    @Override    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {        View view = inflater.inflate(R.layout.fragment_blank, container, false);        unbinder = ButterKnife.bind(this, view);        return view;    }    @Override    public void onActivityCreated(@Nullable Bundle savedInstanceState) {        super.onActivityCreated(savedInstanceState);        String[] data = new String[50];        for (int i = 0; i < 50; i++) {            data[i] = String.valueOf(i);        }        listview.setAdapter(new LsAdapter(getContext(),data));    }    @Override    public void onDestroyView() {        super.onDestroyView();        unbinder.unbind();    }}

2.3 Adapter

需要注意自己ViewHolder的写法

XMl:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical">    <TextView        android:id="@+id/tv"        android:layout_width="match_parent"        android:layout_height="40dp"        android:gravity="center" /></LinearLayout>

Adapter:

package com.u9time.butterknife;import android.content.Context;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.TextView;import butterknife.BindView;import butterknife.ButterKnife;/** * Created by Lenovo on 2017/11/12. */class LsAdapter extends BaseAdapter {    private Context context;    private String[] data;    public LsAdapter(Context context, String[] data) {        this.context = context;        this.data = data;    }    @Override    public int getCount() {        return data.length;    }    @Override    public Object getItem(int position) {        return data[position];    }    @Override    public long getItemId(int position) {        return position;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        ViewHolder holder;        if (convertView == null) {            convertView = View.inflate(context, R.layout.ls_item, null);            holder = new ViewHolder(convertView);            convertView.setTag(holder);        } else {            holder = (ViewHolder) convertView.getTag();        }        holder.setData(data[position]);        return convertView;    }    static class ViewHolder {        @BindView(R.id.tv)        TextView tv;        private String data;        ViewHolder(View view) {            ButterKnife.bind(this, view);        }        public void setData(String data) {            this.data = data;            tv.setText(data);        }    }}

三.主次要点

这个仅仅只是一种注释框架并不属于真真的核心技术,当然不可否认确实很厉害,但是我们一般只是用作来注入控件和点击事件的,其他的数组及字符串等可只作为了解内容.

总结

只是工具,会用即可.