dependencies {
  // 在 API < 14 上的机器支持 WebP 时，需要添加
  compile 'com.facebook.fresco:animated-base-support:0.12.0'
  // 支持 GIF 动图，需要添加
  compile 'com.facebook.fresco:animated-gif:0.12.0'
  // 支持 WebP （静态图+动图），需要添加
  compile 'com.facebook.fresco:animated-webp:0.12.0'
  compile 'com.facebook.fresco:webpsupport:0.12.0'
  // 仅支持 WebP 静态图，需要添加
  compile 'com.facebook.fresco:webpsupport:0.12.0'
}

[MyApplication.java]
public class MyApplication extends Application {
  @Override
  public void onCreate() {
    super.onCreate();
    Fresco.initialize(this);
  }
}

package com.mly.panhouye.frescodemo;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import com.facebook.drawee.backends.pipeline.Fresco;
public class MainActivity extends AppCompatActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Fresco.initialize(this);//需要在setContentView之前初始化
    setContentView(R.layout.activity_main);
  }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  xmlns:fresco="http://schemas.android.com/apk/res-auto"
  android:id="@+id/activity_main"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  tools:context="com.mly.panhouye.frescodemo.MainActivity">
  <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/my_image_view"
    android:layout_centerHorizontal="true"
    android:text="加载网络图片"
    android:onClick="loadInternetImage"
    android:layout_marginTop="12dp"
    android:id="@+id/button" />
  <com.facebook.drawee.view.SimpleDraweeView
    android:id="@+id/my_image_view"
    android:layout_width="400dp"
    android:layout_height="400dp"
    fresco:placeholderImage="@mipmap/ic_launcher"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true" />
</RelativeLayout>

package com.mly.panhouye.frescodemo;
import android.net.Uri;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import com.facebook.drawee.backends.pipeline.Fresco;
import com.facebook.drawee.view.SimpleDraweeView;
public class MainActivity extends AppCompatActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Fresco.initialize(this);//需要在setContentView之前初始化
    setContentView(R.layout.activity_main);
  }
  //点击事件加载网络图片代码
  public void loadInternetImage(View view){
    Uri uri = Uri.parse("http://r.photo.store.qq.com/psb?/V12kkHqD1CWRD4/MeykWt0NXu0stiBFzf378D7ajKSDet6k1.Vaqmq2vps!/r/dKMAAAAAAAAA");
    SimpleDraweeView draweeView = (SimpleDraweeView) findViewById(R.id.my_image_view);
    draweeView.setImageURI(uri);
  }
}