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.
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:
- 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();
}
}
- 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.
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'currently AsmButterknife only supports @BindView,@OnClick. ( ╯□╰ )
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
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distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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