AsmButterknife

AsmButterknife

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Field and method binding for Android views which uses ASM bytecode manipulation to inject boilerplate code for you.

AsmButterknife is similar to Butterknife,except:

• Butterknife uses Annotation Processor,while AsmButterknife uses bytecode manipulation.
• Butterknife Field and method binding can’t uses private modifier,while AsmButterknife can.

Usage

As AsmButterknife doing the exactly same thing as Butterknife,so I’ll keep the usage the same as Butterknife as much as possible.

• inject bytecode for ViewHolder:

static class ViewHolderTest extends RecyclerView.ViewHolder {

    @BindView(R.id.item)
    private TextView tv; //note that we can use private modifier

    @ViewInject //default value: @ViewInject(ViewInject.ViewHolder)
    public ViewHolderTest (View item) {
        super(item);
        this.tv.setText("with @ViewInject,event bytecodes will be inject below super(item)"); //correct,no NullpointerException
    }

    @OnClick(R.id.item)
    private void onClick() { //note that we can use private method
        Toast.makeText(this.tv.getContext(), (String) this.tv.getTag(), Toast.LENGTH_SHORT).show();
    }
}

rebuild and decompile class file,you’ll see:

the code inside red square is what AsmButterknife had injected.

Known that in Butterknife,you will have to call Butterknife.bind somewhere in source code,while AsmButterknife uses bytecode manipulation,there is no need(actually even more complex) to do that,all you need is to tell which method to inject by using @ViewInject annotation.

• inject bytecdoe for Activity:

1. using ViewHolder,known that you have to call the method annotated with ‘@ViewInject(ViewHolder)’ in proper place in source code.

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.tv)
    private TextView mTextView;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        View view = this.getWindow().getDecorView(); 
        this.inject(view); //you have to call the view inject method
    }

    @ViewInject
    private void inject(@NonNull View view){ //View must be the first argumnet
        //leave it empty,bytecode will be injected into this method 
    }

    @OnClick(R.id.tv)
    private void onTextViewClick() {
        Toast.makeText(this, "onTextViewClick", Toast.LENGTH_SHORT).show();
    }
}

2. an easy way to inject bytecode to Activity: by annotated @ViewInject(Activity)

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.tv)
    private TextView mTextView;

    @Override
    @ViewInject(ViewInject.ACTIVITY) //specify Activity
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //with @ViewInject(ViewInject.Activity),bytcode will be injected after setContentView
    }


    @OnClick(R.id.tv)
    private void onTextViewClick() {
        Toast.makeText(this, "onTextViewClick", Toast.LENGTH_SHORT).show();
    }
}

rebuild and decompile class file,you’ll see:

the code inside red square is what AsmButterknife had injected.

Download

Via Gradle:

first add the plugin to your buildscript:

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.whyn:asmbutterknife-plugin:<latest-version>'
    }
}

ps: you can check the newest version:asmbutterknife-plugin

and then apply it in your module:

apply plugin: 'com.android.application'
apply plugin: 'com.whyn.plugin.asmbutterknife'

TODO

currently AsmButterknife only supports @BindView,@OnClick. ( ╯□╰ )

License

Copyright 2018 Whyn

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.