描述

现阶段代替findViewById的

引入使用

启用

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android {
    ...
    viewBinding {
        //开启视图绑定，用来替代findViewById
        //官方文档：https://developer.android.com/topic/libraries/view-binding
        enabled = true
    }
}

然后 onCreate里面就可以这样：

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@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    binding = ActivitySplashBinding.inflate(getLayoutInflater());
    setContentView(binding.getRoot());
    //setContentView(R.layout.activity_splash);
}

然后想要那个带 id 的控件，就不用再 findViewById 了。

直接 binding.id

封装

ViewModelActivity

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import android.os.Bundle;

import androidx.viewbinding.ViewBinding;

import com.example.superutils.reflect.ReflectUtil;

/**
 * 通用ViewModel Activity
 * 包括ViewBinding，主要是处理每次要setContentView
 */
public class BaseViewModelActivity<VB extends ViewBinding> extends BaseLogicActivity{
    protected VB binding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //调用inflate方法，创建viewBinding
        binding = ReflectUtil.newViewBinding(getLayoutInflater(),this.getClass());
        setContentView(binding.getRoot());
    }
}

反射方法类：

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import android.view.LayoutInflater;

import androidx.viewbinding.ViewBinding;

import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;

/**
 * 反射工具类
 */
public class ReflectUtil {
    /**
     * 创建view binding
     */
    public static <VB extends ViewBinding> VB newViewBinding(LayoutInflater layoutInflater, Class<?> clazz) {
        try {
            //获取泛型参数对象
            ParameterizedType type;
            try {
                type = (ParameterizedType) clazz.getGenericSuperclass();
            } catch (ClassCastException e) {
                type = (ParameterizedType) clazz.getSuperclass().getGenericSuperclass();
            }

            //type.actualTypeArguments[0]：ViewBinding
            Class<VB> clazzVB = (Class<VB>) type.getActualTypeArguments()[0];

            //获取inflate方法
            Method inflateMethod = clazzVB.getMethod("inflate", LayoutInflater.class);

            return (VB) inflateMethod.invoke(null, layoutInflater);
        } catch (Exception e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }
}

融合

想要用ViewBinding的直接继承自这个类，然后后面泛型写好对应的类型。

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public class SplashActivity extends BaseViewModelActivity<ActivitySplashBinding> {

然后那个 onCreate 就可以全部删了

Fragment

BaseViewModelDialogFragment

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import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.annotation.Nullable;
import androidx.viewbinding.ViewBinding;

import com.example.superutils.reflect.ReflectUtil;

public abstract class BaseViewModelDialogFragment<VB extends ViewBinding> extends BaseDialogFragment{
    protected VB binding;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //调用inflate方法，创建viewBinding
        binding = ReflectUtil.newViewBinding(getLayoutInflater(),this.getClass());
    }

    @Override
    protected View getLayoutView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return binding.getRoot();
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        binding = null;
    }
}

使用

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public class TermServiceDialogFragment extends BaseViewModelDialogFragment<FragmentDialogTermServiceBinding> {

然后就一样用了

同时要特别注意。如果使用的 Fragment 中有 getLayoutView方法。

记得去掉。