关于Android中Builder的学习

/*
* @description ImageFillUtil
* 图片的填充工具类：
* 注意Picasso占内存且在加载的时候会有闪烁，
* 而Glide不占内存不闪烁，但会引起图片的失真
* 注意：所有的图片尺寸均为 dip
* @author Nathaniel-nathanwriting@126.com
* @time 2016/8/17-22:45
* @version v1.0.0
*/
public class ImageFillUtils {
public static final int TYPE_NORMAL = 0; // 正常，不做任何处理
public static final int TYPE_CIRCLE = 1; // 圆形图片
public static final int TYPE_ROUND = 2; // 圆角图片

private static final String TAG = ImageFillUtils.class.getSimpleName();
private static final int IMAGE_DEFAULT_RADIUS = 10; // 默认圆角半径
private static final int IMAGE_DEFAULT_MARGIN = 0; // 默认外边距
private static final int DEFAULT_IMAGE_WIDTH = 320; // 默认宽
private static final int DEFAULT_IMAGE_HEIGHT = 240; // 默认高

@SuppressLint("StaticFieldLeak")
private static Builder builder;

public static void clearGlide(Context context) {
Glide.get(context).clearDiskCache();
Glide.get(context).clearMemory();
}

public static void clearGlide(View target) {
Glide.clear(target);
}

public static Builder builder(@NonNull Context context, @NonNull ImageView imageView) {
if (builder == null) {
builder = new Builder(context, imageView);
}
return builder;
}

public static class Builder {
private Context context;
private ImageView imageView;
private int resourceId;
private int placeHolder;
private int errorResource;
private int type;
private int radius;
private int margin; // dip
private boolean gifable;
private boolean fitable;
private boolean fadeable;
private boolean cacheable;
private boolean fixable;
private boolean resizeable;
private String imageUrl;
private int resizeX;
private int resizeY;
private RequestManager glideRequest;
private Picasso picassoRequest;
private RequestCreator requestCreator;
private DrawableTypeRequest drawableTypeRequest;

private Builder(Context context, ImageView imageView) {
if (context == null || imageView == null) {
throw new IllegalArgumentException("IllegalArgumentException in " + TAG);
}

this.context = context;
this.imageView = imageView;
}

private int dip2px(int dipValue) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (dipValue * scale + 0.5f);
}

public Builder setPlaceHolder(int placeHolder) {
this.placeHolder = placeHolder;
return this;
}

public Builder setType(int type) {
this.type = type;
return this;
}

public Builder setRadius(int radius) {
this.radius = radius;
return this;
}

public Builder setMargin(int margin) {
this.margin = margin;
return this;
}

public Builder setFixable(boolean fixable) {
this.fixable = fixable;
return this;
}

public Builder setGifable(boolean gifable) {
this.gifable = gifable;
return this;
}

public Builder setImageUrl(String imageUrl) {
this.imageUrl = imageUrl;
return this;
}

public Builder setResourceId(int resourceId) {
this.resourceId = resourceId;
return this;
}

public Builder setErrorResource(int errorResource) {
this.errorResource = errorResource;
return this;
}

public Builder setResizeable(boolean resizeable) {
this.resizeable = resizeable;
return this;
}

public Builder setCacheable(boolean cacheable) {
this.cacheable = cacheable;
return this;
}

public Builder setFitable(boolean fitable) {
this.fitable = fitable;
return this;
}

public Builder setFadeable(boolean fadeable) {
this.fadeable = fadeable;
return this;
}

public Builder resize(int resizeX, int resizeY) {
this.resizeX = resizeX;
this.resizeY = resizeY;
return this;
}

public void setPicassoImage() {
picassoRequest = Picasso.with(context);

// 加载本地资源文件
if (resourceId > 0) {
requestCreator = picassoRequest.load(resourceId);
}

// 加载网络资源文件
if (!TextUtils.isEmpty(imageUrl)) {
requestCreator = picassoRequest.load(imageUrl);
}

// 占位符
if (placeHolder > 0) {
requestCreator.placeholder(placeHolder);
}

// 展示类型
switch (type) {
case TYPE_CIRCLE:
requestCreator.transform(new PicassoCircleTransform());
break;

case TYPE_ROUND:
if (radius == 0) {
radius = IMAGE_DEFAULT_RADIUS;
}
if (margin == 0) {
margin = IMAGE_DEFAULT_MARGIN;
}
requestCreator.transform(new PicassoRoundTransform(radius, margin));
break;
}

if (errorResource > 0) {
requestCreator.error(errorResource);
}

if (fixable) {
requestCreator.fit();
}

if (resizeable) {
if (resizeX == 0) {
resizeX = DEFAULT_IMAGE_WIDTH;
}

if (resizeY == 0) {
resizeY = DEFAULT_IMAGE_HEIGHT;
}

requestCreator.resize(dip2px(resizeX), dip2px(resizeY));
}

requestCreator.priority(Picasso.Priority.HIGH);

requestCreator.into(imageView);
}

public void setGlideImage() {
glideRequest = Glide.with(context);

if (resourceId > 0) {
drawableTypeRequest = glideRequest.load(resourceId);
}

if (!TextUtils.isEmpty(imageUrl)) {
drawableTypeRequest = glideRequest.load(imageUrl);
}

switch (type) {
case TYPE_CIRCLE:
drawableTypeRequest.transform(new GlideCircleTransform(context));
break;

case TYPE_ROUND:
if (radius == 0) {
radius = IMAGE_DEFAULT_RADIUS;
}
drawableTypeRequest.transform(new GlideRoundTransform(context, radius));
break;
}

if (cacheable) {
drawableTypeRequest.diskCacheStrategy(DiskCacheStrategy.ALL);
}

if (fadeable) {
drawableTypeRequest.crossFade();
}

if (resizeable) {
if (resizeX == 0) {
resizeX = DEFAULT_IMAGE_WIDTH;
}

if (resizeY == 0) {
resizeY = DEFAULT_IMAGE_HEIGHT;
}

drawableTypeRequest.override(dip2px(resizeX), dip2px(resizeY));
}

if (placeHolder > 0) {
drawableTypeRequest.placeholder(placeHolder);
}

if (errorResource > 0) {
drawableTypeRequest.error(errorResource);
}

if (gifable) {
drawableTypeRequest.asGif();
}

// 根据ImageView缩放
drawableTypeRequest.into(new SimpleTarget<Bitmap>(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL) {
@Override
public void onResourceReady(Bitmap bitmap, GlideAnimation<? super Bitmap> glideAnimation) {
int imageWidth = bitmap.getWidth();
int imageHeight = bitmap.getHeight();
int height = imageView.getWidth() * imageHeight / imageWidth;
ViewGroup.LayoutParams layoutParams = imageView.getLayoutParams();
layoutParams.height = height;
layoutParams.width = imageView.getWidth();
imageView.setImageBitmap(bitmap);
}
});
}
}
}

调用

ImageFillUtils.builder(context, imageView).setImageUrl(url).setPlaceHolder(R.drawable.img_transition_default).setErrorResource(R.drawable.img_transition_default).setPicassoImage(); // .setGlideImage();