Glide自v3.0到v4.0使用，发生了一些比较大的改变，使用方式和编程模型有了新的变化，这些变化，使得Glide的功能更加强大，性能更加优良，提供了开放的编程接口，便于开发者自定制，以适应自有项目的定制化开发。
本例给出一些最新Android Glide 4.0的新变化、新模型的简单使用方式。
写一个简单垂直线性布局：

<?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="zhangphil.phildemo.MainActivity">

    <ImageView
        android:id="@+id/image1"
        android:layout_width="100dp"
        android:layout_height="100dp" />

    <ImageView
        android:id="@+id/image2"
        android:layout_width="100dp"
        android:layout_height="100dp" />

    <ImageView
        android:id="@+id/image3"
        android:layout_width="100dp"
        android:layout_height="100dp" />

    <ImageView
        android:id="@+id/image4"
        android:layout_width="100dp"
        android:layout_height="100dp" />

</LinearLayout>

测试的MainActivity.java，在这里面有四个不同的新版Glide 4.0使用方式：

package zhangphil.phildemo;

import android.graphics.drawable.Drawable;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;

import com.bumptech.glide.Glide;
import com.bumptech.glide.Priority;
import com.bumptech.glide.RequestBuilder;
import com.bumptech.glide.load.DataSource;
import com.bumptech.glide.load.engine.DiskCacheStrategy;
import com.bumptech.glide.load.engine.GlideException;
import com.bumptech.glide.load.resource.drawable.DrawableTransitionOptions;
import com.bumptech.glide.request.RequestListener;
import com.bumptech.glide.request.RequestOptions;
import com.bumptech.glide.request.target.Target;

public class MainActivity extends AppCompatActivity {
    private String url = "https://www.baidu.com/img/bd_logo1.png";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ImageView image1 = (ImageView) findViewById(R.id.image1);
        ImageView image2 = (ImageView) findViewById(R.id.image2);
        ImageView image3 = (ImageView) findViewById(R.id.image3);
        ImageView image4 = (ImageView) findViewById(R.id.image4);

        load1(image1);
        load2(image2);
        load3(image3);
        load4(image4);
    }

    private void load1(ImageView image) {
        Glide.with(this)
                .load(url)
                .apply(new RequestOptions().circleCrop().placeholder(R.mipmap.ic_launcher))
                .transition(new DrawableTransitionOptions().crossFade(2000))
                .into(image);
    }

    private void load2(ImageView image) {
        RequestOptions options = new RequestOptions()
                .centerCrop()
                .placeholder(R.mipmap.ic_launcher_round)
                .error(android.R.drawable.stat_notify_error)
                .priority(Priority.HIGH)
                //.skipMemoryCache(true)
                .diskCacheStrategy(DiskCacheStrategy.AUTOMATIC);

        Glide.with(this)
                .load(url)
                .apply(options)
                .into(image);
    }

    private void load3(ImageView image) {
        Glide.with(this)
                .load(url)
                .listener(new RequestListener<Drawable>() {
                    @Override
                    public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<Drawable> target, boolean isFirstResource) {
                        return false;
                    }

                    @Override
                    public boolean onResourceReady(Drawable resource, Object model, Target<Drawable> target, DataSource dataSource, boolean isFirstResource) {
                        return false;
                    }
                })
                .apply(new RequestOptions().centerInside())
                .thumbnail(Glide.with(this).load(R.mipmap.ic_launcher))
                .into(image);
    }

    private void load4(ImageView image) {
        RequestBuilder<Drawable> mRequestBuilder = Glide.with(this).load(url);

        mRequestBuilder.listener(new RequestListener<Drawable>() {
            @Override
            public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<Drawable> target, boolean isFirstResource) {
                return false;
            }

            @Override
            public boolean onResourceReady(Drawable resource, Object model, Target<Drawable> target, DataSource dataSource, boolean isFirstResource) {
                return false;
            }
        }).transition(new DrawableTransitionOptions().crossFade(2000))
                .apply(new RequestOptions().circleCrop())
                .into(image);
    }
}

本例给出了几个不同的方式使用新版Glide 4.0加载网络图片，对比这四种方式，可以举一反三变化出更多使用方法。

不要忘了添加读写存储和访问网络的权限：

    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

代码运行结果：

附录：

1，Glide在github上的开源项目主页：https://github.com/bumptech/glide