Fresco使用PhotoDraweeView 实现图片的手势缩放

我会带着你远行 2022-04-15 02:55 276阅读 0赞

1.gradle引入Fresco

compile 'com.facebook.fresco:fresco:0.11.0+'

2.在application中初始化Fresco

Fresco.initialize(this, ImagePipelineConfigFactory.getImagePipelineConfig(this));

3.PhotoDraweeView的下载地址  
  [https://github.com/ongakuer/PhotoDraweeView][https_github.com_ongakuer_PhotoDraweeView]

4.PhotoDraweeView结构

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3N1bnNoaW5lXzA3MDc_size_16_color_FFFFFF_t_70][]

5.添加PhotoDraweeView控件

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        xmlns:fresco="http://schemas.android.com/apk/res-auto"
        android:orientation="vertical">
    
        <me.relex.photodraweeview.PhotoDraweeView
            android:id="@+id/pv_picture"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
          />
    
    </LinearLayout>

6.实现

PipelineDraweeControllerBuilder controller = Fresco.newDraweeControllerBuilder();
    controller.setUri( Uri.parse(photopath));
    controller.setOldController(pv_picture.getController());
    controller.setControllerListener(new BaseControllerListener<ImageInfo>() {
       @Override
       public void onFinalImageSet(String id, ImageInfo imageInfo, Animatable animatable) {
          super.onFinalImageSet(id, imageInfo, animatable);
          if (imageInfo == null) {
             return;
          }
          pv_picture.update(imageInfo.getWidth(), imageInfo.getHeight());
       }
    });
    pv_picture.setController(controller.build());

7.在PhotoDraweeView下面的方法里。可以使用Matrix对象修改图片显示属性

@Override protected void onDraw( Canvas canvas) {
        int saveCount = canvas.save();
       //这里改显示比例
        canvas.concat(mAttacher.getDrawMatrix());
        super.onDraw(canvas);
        canvas.restoreToCount(saveCount);
    }

8.上面第二点ImagePipelineConfigFactory，是关于Fresco的初始化配置的，代码如下：

import android.content.Context;
    import com.facebook.cache.disk.DiskCacheConfig;
    import com.facebook.common.internal.Supplier;
    import com.facebook.imagepipeline.cache.MemoryCacheParams;
    import com.facebook.imagepipeline.core.ImagePipelineConfig;
    
    
    /**
     * Creates ImagePipeline configuration for the sample app
     */
    public class ImagePipelineConfigFactory {
      private static final String IMAGE_PIPELINE_CACHE_DIR = "imagepipeline_cache";
    
      private static ImagePipelineConfig sImagePipelineConfig;
    
      /**
       * Creates config using android http stack as network backend.
       */
      public static ImagePipelineConfig getImagePipelineConfig(Context context) {
        if (sImagePipelineConfig == null) {
          ImagePipelineConfig.Builder configBuilder = ImagePipelineConfig.newBuilder(context);
          configureCaches(configBuilder, context);
          sImagePipelineConfig = configBuilder.build();
        }
        return sImagePipelineConfig;
      }
    
      
    
      /**
       * Configures disk and memory cache not to exceed common limits
       */
      private static void configureCaches(
          ImagePipelineConfig.Builder configBuilder,
          Context context) {
          //内存缓存配置
          final MemoryCacheParams bitmapCacheParams = new MemoryCacheParams(
            ConfigConstants.MAX_MEMORY_CACHE_SIZE, // Max total size of elements in the cache
            ConfigConstants.MAX_CACHE,                     // Max entries in the cache
            ConfigConstants.MAX_MEMORY_CACHE_SIZE, // Max total size of elements in eviction queue
            ConfigConstants.MAX_CACHE,                     // Max length of eviction queue
            ConfigConstants.MAX_CACHE);                    // Max cache entry size
        configBuilder
            //内存图片缓存数量
            .setBitmapMemoryCacheParamsSupplier(
                new Supplier<MemoryCacheParams>() {
                  @Override
             public MemoryCacheParams get() {
                    return bitmapCacheParams;
                  }
                })
            .setMainDiskCacheConfig(
              //磁盘缓存设置
                DiskCacheConfig.newBuilder()
                    .setBaseDirectoryPath(context.getApplicationContext().getCacheDir()) //基本路径名
                    .setBaseDirectoryName(IMAGE_PIPELINE_CACHE_DIR) //基本路径名名称
                    .setMaxCacheSize(ConfigConstants.MAX_DISK_CACHE_SIZE)//磁盘缓存的最大大小
                    .build());
      }
    
    }

[https_github.com_ongakuer_PhotoDraweeView]: https://link.jianshu.com/?t=https://github.com/ongakuer/PhotoDraweeView
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3N1bnNoaW5lXzA3MDc_size_16_color_FFFFFF_t_70]: /images/20220415/62e8f70b1421490eaf00694c2ac39da1.png