Android实现多图选择
一、技术概述
Android项目中经常会使用多图上传功能，但是Android自带的选择器只能够选择一张图片。这个选择可以适用于Android项目中的多图显示功能。
二、技术详述
布局主要是简单的RecyclerView以及一个拖动到此处删除的框
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/publish_article_recycler"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="16dp"
android:layout_marginRight="16dp"
android:overScrollMode="never" />
<TextView
android:id="@+id/tv_delete_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
android:background="@color/subColor"
android:drawableTop="@drawable/picture_icon_delete"
android:drawablePadding="5dp"
android:gravity="center"
android:paddingTop="8dp"
android:paddingBottom="8dp"
android:text="@string/app_drag_delete"
android:textColor="@color/app_color_white"
android:textSize="12sp"
android:visibility="gone"
tools:visibility="visible" />
定义Adaptor工具类——GridImageAdapter
public class GridImageAdapter extends
RecyclerView.Adapter<GridImageAdapter.ViewHolder> {
public static final String TAG = "PictureSelector";
public static final int TYPE_CAMERA = 1;
public static final int TYPE_PICTURE = 2;
private LayoutInflater mInflater;
private List<LocalMedia> list = new ArrayList<>();
private int selectMax = 9;
/**
* 点击添加图片跳转
*/
private onAddPicClickListener mOnAddPicClickListener;
public interface onAddPicClickListener {
void onAddPicClick();
}
/**
* 删除
*/
public void delete(int position) {
try {
if (position != RecyclerView.NO_POSITION && list.size() > position) {
list.remove(position);
notifyItemRemoved(position);
notifyItemRangeChanged(position, list.size());
}
} catch (Exception e) {
e.printStackTrace();
}
}
public GridImageAdapter(Context context, onAddPicClickListener mOnAddPicClickListener) {
this.mInflater = LayoutInflater.from(context);
this.mOnAddPicClickListener = mOnAddPicClickListener;
}
public void setSelectMax(int selectMax) {
this.selectMax = selectMax;
}
public void setList(List<LocalMedia> list) {
this.list = list;
}
public List<LocalMedia> getData() {
return list == null ? new ArrayList<>() : list;
}
public void remove(int position) {
if (list != null && position < list.size()) {
list.remove(position);
}
}
public class ViewHolder extends RecyclerView.ViewHolder {
ImageView mImg;
ImageView mIvDel;
TextView tvDuration;
public ViewHolder(View view) {
super(view);
mImg = view.findViewById(R.id.fiv);
mIvDel = view.findViewById(R.id.iv_del);
tvDuration = view.findViewById(R.id.tv_duration);
}
}
@Override
public int getItemCount() {
if (list.size() < selectMax) {
return list.size() + 1;
} else {
return list.size();
}
}
@Override
public int getItemViewType(int position) {
if (isShowAddItem(position)) {
return TYPE_CAMERA;
} else {
return TYPE_PICTURE;
}
}
/**
* 创建ViewHolder
*/
@Override
public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = mInflater.inflate(R.layout.gv_filter_image,
viewGroup, false);
final ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
private boolean isShowAddItem(int position) {
int size = list.size() == 0 ? 0 : list.size();
return position == size;
}
/**
* 设置值
*/
@Override
public void onBindViewHolder(final ViewHolder viewHolder, final int position) {
//少于8张，显示继续添加的图标
if (getItemViewType(position) == TYPE_CAMERA) {
viewHolder.mImg.setImageResource(R.drawable.ic_add_image);
viewHolder.mImg.setOnClickListener(v -> mOnAddPicClickListener.onAddPicClick());
viewHolder.mIvDel.setVisibility(View.INVISIBLE);
} else {
viewHolder.mIvDel.setVisibility(View.VISIBLE);
viewHolder.mIvDel.setOnClickListener(view -> {
int index = viewHolder.getAdapterPosition();
// 这里有时会返回-1造成数据下标越界,具体可参考getAdapterPosition()源码，
// 通过源码分析应该是bindViewHolder()暂未绘制完成导致，知道原因的也可联系我~感谢
if (index != RecyclerView.NO_POSITION && list.size() > index) {
list.remove(index);
notifyItemRemoved(index);
notifyItemRangeChanged(index, list.size());
}
});
LocalMedia media = list.get(position);
if (media == null
|| TextUtils.isEmpty(media.getPath())) {
return;
}
int chooseModel = media.getChooseModel();
String path;
if (media.isCut() && !media.isCompressed()) {
// 裁剪过
path = media.getCutPath();
} else if (media.isCompressed() || (media.isCut() && media.isCompressed())) {
// 压缩过,或者裁剪同时压缩过,以最终压缩过图片为准
path = media.getCompressPath();
} else {
// 原图
path = media.getPath();
}
Log.i(TAG, "原图地址::" + media.getPath());
if (media.isCut()) {
Log.i(TAG, "裁剪地址::" + media.getCutPath());
}
if (media.isCompressed()) {
Log.i(TAG, "压缩地址::" + media.getCompressPath());
Log.i(TAG, "压缩后文件大小::" + new File(media.getCompressPath()).length() / 1024 + "k");
}
if (!TextUtils.isEmpty(media.getAndroidQToPath())) {
Log.i(TAG, "Android Q特有地址::" + media.getAndroidQToPath());
}
if (media.isOriginal()) {
Log.i(TAG, "是否开启原图功能::" + true);
Log.i(TAG, "开启原图功能后地址::" + media.getOriginalPath());
}
long duration = media.getDuration();
viewHolder.tvDuration.setVisibility(PictureMimeType.isHasVideo(media.getMimeType())
? View.VISIBLE : View.GONE);
if (chooseModel == PictureMimeType.ofAudio()) {
viewHolder.tvDuration.setVisibility(View.VISIBLE);
viewHolder.tvDuration.setCompoundDrawablesRelativeWithIntrinsicBounds
(R.drawable.picture_icon_audio, 0, 0, 0);
} else {
viewHolder.tvDuration.setCompoundDrawablesRelativeWithIntrinsicBounds
(R.drawable.picture_icon_video, 0, 0, 0);
}
viewHolder.tvDuration.setText(DateUtils.formatDurationTime(duration));
if (chooseModel == PictureMimeType.ofAudio()) {
viewHolder.mImg.setImageResource(R.drawable.picture_audio_placeholder);
} else {
Glide.with(viewHolder.itemView.getContext())
.load(PictureMimeType.isContent(path) && !media.isCut() && !media.isCompressed() ? Uri.parse(path)
: path)
.centerCrop()
.placeholder(R.color.app_color_f6)
.diskCacheStrategy(DiskCacheStrategy.ALL)
.into(viewHolder.mImg);
}
//itemView 的点击事件
if (mItemClickListener != null) {
viewHolder.itemView.setOnClickListener(v -> {
int adapterPosition = viewHolder.getAdapterPosition();
mItemClickListener.onItemClick(v, adapterPosition);
});
}
if (mItemLongClickListener != null) {
viewHolder.itemView.setOnLongClickListener(v -> {
int adapterPosition = viewHolder.getAdapterPosition();
mItemLongClickListener.onItemLongClick(viewHolder, adapterPosition, v);
return true;
});
}
}
}
private OnItemClickListener mItemClickListener;
public void setOnItemClickListener(OnItemClickListener l) {
this.mItemClickListener = l;
}
private OnItemLongClickListener mItemLongClickListener;
public void setItemLongClickListener(OnItemLongClickListener l) {
this.mItemLongClickListener = l;
}
}
定义获取图片缓存工具类——ImageCacheUtils
public class ImageCacheUtils {
/**
* 根据url获取图片缓存
* Glide 4.x请调用此方法
* 注意：此方法必须在子线程中进行
*
* @param context
* @param url
* @return
*/
public static File getCacheFileTo4x(Context context, String url) {
try {
return Glide.with(context).downloadOnly().load(url).submit().get();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
/**
* 根据url获取图片缓存
* Glide 3.x请调用此方法
* 注意：此方法必须在子线程中进行
*
* @param context
* @param url
* @return
*/
public static File getCacheFileTo3x(Context context, String url) {
try {
return Glide.with(context).load(url).downloadOnly(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL).get();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
定义Glide引擎工具类——GlideEngine
public class GlideEngine implements ImageEngine {
/**
* 加载图片
*
* @param context
* @param url
* @param imageView
*/
@Override
public void loadImage(@NonNull Context context, @NonNull String url, @NonNull ImageView imageView) {
Glide.with(context)
.load(url)
.into(imageView);
}
/**
* 加载网络图片适配长图方案
* # 注意：此方法只有加载网络图片才会回调
*
* @param context
* @param url
* @param imageView
* @param longImageView
* @param callback 网络图片加载回调监听 {link after version 2.5.1 Please use the #OnImageCompleteCallback#}
*/
@Override
public void loadImage(@NonNull Context context, @NonNull String url,
@NonNull final ImageView imageView,
final SubsamplingScaleImageView longImageView, final OnImageCompleteCallback callback) {
Glide.with(context)
.asBitmap()
.load(url)
.into(new ImageViewTarget<Bitmap>(imageView) {
@Override
public void onLoadStarted(@Nullable Drawable placeholder) {
super.onLoadStarted(placeholder);
if (callback != null) {
callback.onShowLoading();
}
}
@Override
public void onLoadFailed(@Nullable Drawable errorDrawable) {
super.onLoadFailed(errorDrawable);
if (callback != null) {
callback.onHideLoading();
}
}
@Override
protected void setResource(@Nullable Bitmap resource) {
if (callback != null) {
callback.onHideLoading();
}
if (resource != null) {
boolean eqLongImage = MediaUtils.isLongImg(resource.getWidth(),
resource.getHeight());
longImageView.setVisibility(eqLongImage ? View.VISIBLE : View.GONE);
imageView.setVisibility(eqLongImage ? View.GONE : View.VISIBLE);
if (eqLongImage) {
// 加载长图
longImageView.setQuickScaleEnabled(true);
longImageView.setZoomEnabled(true);
longImageView.setPanEnabled(true);
longImageView.setDoubleTapZoomDuration(100);
longImageView.setMinimumScaleType(SubsamplingScaleImageView.SCALE_TYPE_CENTER_CROP);
longImageView.setDoubleTapZoomDpi(SubsamplingScaleImageView.ZOOM_FOCUS_CENTER);
longImageView.setImage(ImageSource.bitmap(resource),
new ImageViewState(0, new PointF(0, 0), 0));
} else {
// 普通图片
imageView.setImageBitmap(resource);
}
}
}
});
}
/**
* 加载网络图片适配长图方案
* # 注意：此方法只有加载网络图片才会回调
*
* @param context
* @param url
* @param imageView
* @param longImageView
* @ 已废弃
*/
@Override
public void loadImage(@NonNull Context context, @NonNull String url,
@NonNull final ImageView imageView,
final SubsamplingScaleImageView longImageView) {
Glide.with(context)
.asBitmap()
.load(url)
.into(new ImageViewTarget<Bitmap>(imageView) {
@Override
protected void setResource(@Nullable Bitmap resource) {
if (resource != null) {
boolean eqLongImage = MediaUtils.isLongImg(resource.getWidth(),
resource.getHeight());
longImageView.setVisibility(eqLongImage ? View.VISIBLE : View.GONE);
imageView.setVisibility(eqLongImage ? View.GONE : View.VISIBLE);
if (eqLongImage) {
// 加载长图
longImageView.setQuickScaleEnabled(true);
longImageView.setZoomEnabled(true);
longImageView.setPanEnabled(true);
longImageView.setDoubleTapZoomDuration(100);
longImageView.setMinimumScaleType(SubsamplingScaleImageView.SCALE_TYPE_CENTER_CROP);
longImageView.setDoubleTapZoomDpi(SubsamplingScaleImageView.ZOOM_FOCUS_CENTER);
longImageView.setImage(ImageSource.bitmap(resource),
new ImageViewState(0, new PointF(0, 0), 0));
} else {
// 普通图片
imageView.setImageBitmap(resource);
}
}
}
});
}
/**
* 加载相册目录
*
* @param context 上下文
* @param url 图片路径
* @param imageView 承载图片ImageView
*/
@Override
public void loadFolderImage(@NonNull final Context context, @NonNull String url, @NonNull final ImageView imageView) {
Glide.with(context)
.asBitmap()
.load(url)
.override(180, 180)
.centerCrop()
.sizeMultiplier(0.5f)
.apply(new RequestOptions().placeholder(R.drawable.picture_image_placeholder))
.into(new BitmapImageViewTarget(imageView) {
@Override
protected void setResource(Bitmap resource) {
RoundedBitmapDrawable circularBitmapDrawable =
RoundedBitmapDrawableFactory.
create(context.getResources(), resource);
circularBitmapDrawable.setCornerRadius(8);
imageView.setImageDrawable(circularBitmapDrawable);
}
});
}
/**
* 加载gif
*
* @param context 上下文
* @param url 图片路径
* @param imageView 承载图片ImageView
*/
@Override
public void loadAsGifImage(@NonNull Context context, @NonNull String url,
@NonNull ImageView imageView) {
Glide.with(context)
.asGif()
.load(url)
.into(imageView);
}
/**
* 加载图片列表图片
*
* @param context 上下文
* @param url 图片路径
* @param imageView 承载图片ImageView
*/
@Override
public void loadGridImage(@NonNull Context context, @NonNull String url, @NonNull ImageView imageView) {
Glide.with(context)
.load(url)
.override(200, 200)
.centerCrop()
.apply(new RequestOptions().placeholder(R.drawable.picture_image_placeholder))
.into(imageView);
}
private GlideEngine() {
}
private static GlideEngine instance;
public static GlideEngine createGlideEngine() {
if (null == instance) {
synchronized (GlideEngine.class) {
if (null == instance) {
instance = new GlideEngine();
}
}
}
return instance;
}
}
最后一个工具类FullyGridLayoutManager
public class FullyGridLayoutManager extends GridLayoutManager {
public FullyGridLayoutManager(Context context, int spanCount) {
super(context, spanCount);
}
public FullyGridLayoutManager(Context context, int spanCount, int orientation, boolean reverseLayout) {
super(context, spanCount, orientation, reverseLayout);
}
private int[] mMeasuredDimension = new int[2];
@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state, int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
int width = 0;
int height = 0;
int count = getItemCount();
int span = getSpanCount();
for (int i = 0; i < count; i++) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);
if (getOrientation() == HORIZONTAL) {
if (i % span == 0) {
width = width + mMeasuredDimension[0];
}
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
if (i % span == 0) {
height = height + mMeasuredDimension[1];
}
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}
switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
setMeasuredDimension(width, height);
}
final RecyclerView.State mState = new RecyclerView.State();
private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
int itemCount = mState.getItemCount();
if (position < itemCount) {
try {
View view = recycler.getViewForPosition(0);
if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight(), p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom(), p.height);
view.measure(childWidthSpec, childHeightSpec);
measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
做好以上工具类的创建后，就可以开始搭建图片选择器了
首先初始化RecylerView以及GridImageAdapter
mRecyclerView = findViewById(R.id.publish_article_recycler);
FullyGridLayoutManager manager = new FullyGridLayoutManager(this,
4, GridLayoutManager.VERTICAL, false);
mRecyclerView.setLayoutManager(manager);
mRecyclerView.addItemDecoration(new GridSpacingItemDecoration(4,
ScreenUtils.dip2px(this, 8), false));
mAdapter = new GridImageAdapter(getContext(), onAddPicClickListener);
mAdapter.setSelectMax(maxSelectNum);
给adaptor添加点击事件
mAdapter.setOnItemClickListener((v, position) -> {
List<LocalMedia> selectList = mAdapter.getData();
if (selectList.size() > 0) {
LocalMedia media = selectList.get(position);
String mimeType = media.getMimeType();
int mediaType = PictureMimeType.getMimeType(mimeType);
switch (mediaType) {
case PictureConfig.TYPE_VIDEO:
// 预览视频
PictureSelector.create(PublishArticle.this)
.themeStyle(R.style.picture_default_style)
.setPictureStyle(mPictureParameterStyle)// 动态自定义相册主题
.externalPictureVideo(TextUtils.isEmpty(media.getAndroidQToPath()) ? media.getPath() : media.getAndroidQToPath());
break;
default:
// 预览图片 可自定长按保存路径
// PictureWindowAnimationStyle animationStyle = new PictureWindowAnimationStyle();
// animationStyle.activityPreviewEnterAnimation = R.anim.picture_anim_up_in;
// animationStyle.activityPreviewExitAnimation = R.anim.picture_anim_down_out;
PictureSelector.create(PublishArticle.this)
.themeStyle(R.style.picture_default_style) // xml设置主题
.setPictureStyle(mPictureParameterStyle)// 动态自定义相册主题
//.setPictureWindowAnimationStyle(animationStyle)// 自定义页面启动动画
.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED)// 设置相册Activity方向，不设置默认使用系统
.isNotPreviewDownload(true)// 预览图片长按是否可以下载
//.bindCustomPlayVideoCallback(new MyVideoSelectedPlayCallback(getContext()))// 自定义播放回调控制，用户可以使用自己的视频播放界面
.imageEngine(GlideEngine.createGlideEngine())// 外部传入图片加载引擎，必传项
.openExternalPreview(position, selectList);
break;
}
}
});
mAdapter.setItemLongClickListener((holder, position, v) -> {
//如果item不是最后一个，则执行拖拽
needScaleBig = true;
needScaleSmall = true;
int size = mAdapter.getData().size();
if (size != maxSelectNum) {
mItemTouchHelper.startDrag(holder);
return;
}
if (holder.getLayoutPosition() != size - 1) {
mItemTouchHelper.startDrag(holder);
}
});
mRecyclerView.setAdapter(mAdapter);
mDragListener = new DragListener() {
@Override
public void deleteState(boolean isDelete) {
if (isDelete) {
tvDeleteText.setText(getString(R.string.app_let_go_drag_delete));
tvDeleteText.setCompoundDrawablesRelativeWithIntrinsicBounds(0, R.drawable.ic_let_go_delete, 0, 0);
} else {
tvDeleteText.setText(getString(R.string.app_drag_delete));
tvDeleteText.setCompoundDrawablesRelativeWithIntrinsicBounds(0, R.drawable.picture_icon_delete, 0, 0);
}
}
@Override
public void dragState(boolean isStart) {
int visibility = tvDeleteText.getVisibility();
if (isStart) {
if (visibility == View.GONE) {
tvDeleteText.animate().alpha(1).setDuration(300).setInterpolator(new AccelerateInterpolator());
tvDeleteText.setVisibility(View.VISIBLE);
}
} else {
if (visibility == View.VISIBLE) {
tvDeleteText.animate().alpha(0).setDuration(300).setInterpolator(new AccelerateInterpolator());
tvDeleteText.setVisibility(View.GONE);
}
}
}
};
触摸事件的编写
mItemTouchHelper = new ItemTouchHelper(new ItemTouchHelper.Callback() {
@Override
public boolean isLongPressDragEnabled() {
return true;
}
@Override
public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int direction) {
}
@Override
public int getMovementFlags(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder) {
int itemViewType = viewHolder.getItemViewType();
if (itemViewType != GridImageAdapter.TYPE_CAMERA) {
viewHolder.itemView.setAlpha(0.7f);
}
return makeMovementFlags(ItemTouchHelper.DOWN | ItemTouchHelper.UP
| ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT, 0);
}
@Override
public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target) {
//得到item原来的position
try {
int fromPosition = viewHolder.getAdapterPosition();
//得到目标position
int toPosition = target.getAdapterPosition();
int itemViewType = target.getItemViewType();
if (itemViewType != GridImageAdapter.TYPE_CAMERA) {
if (fromPosition < toPosition) {
for (int i = fromPosition; i < toPosition; i++) {
Collections.swap(mAdapter.getData(), i, i + 1);
}
} else {
for (int i = fromPosition; i > toPosition; i--) {
Collections.swap(mAdapter.getData(), i, i - 1);
}
}
mAdapter.notifyItemMoved(fromPosition, toPosition);
}
} catch (Exception e) {
e.printStackTrace();
}
return true;
}
@Override
public void onChildDraw(@NonNull Canvas c, @NonNull RecyclerView recyclerView,
@NonNull RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) {
int itemViewType = viewHolder.getItemViewType();
if (itemViewType != GridImageAdapter.TYPE_CAMERA) {
if (null == mDragListener) {
return;
}
if (needScaleBig) {
//如果需要执行放大动画
viewHolder.itemView.animate().scaleXBy(0.1f).scaleYBy(0.1f).setDuration(100);
//执行完成放大动画,标记改掉
needScaleBig = false;
//默认不需要执行缩小动画，当执行完成放大 并且松手后才允许执行
needScaleSmall = false;
}
int sh = recyclerView.getHeight() + tvDeleteText.getHeight();
int ry = tvDeleteText.getBottom() - sh;
if (dY >= ry) {
//拖到删除处
mDragListener.deleteState(true);
if (isUpward) {
//在删除处放手，则删除item
viewHolder.itemView.setVisibility(View.INVISIBLE);
mAdapter.delete(viewHolder.getAdapterPosition());
resetState();
return;
}
} else {//没有到删除处
if (View.INVISIBLE == viewHolder.itemView.getVisibility()) {
//如果viewHolder不可见，则表示用户放手，重置删除区域状态
mDragListener.dragState(false);
}
if (needScaleSmall) {//需要松手后才能执行
viewHolder.itemView.animate().scaleXBy(1f).scaleYBy(1f).setDuration(100);
}
mDragListener.deleteState(false);
}
super.onChildDraw(c, recyclerView, viewHolder, dX, dY, actionState, isCurrentlyActive);
}
}
@Override
public void onSelectedChanged(@Nullable RecyclerView.ViewHolder viewHolder, int actionState) {
int itemViewType = viewHolder != null ? viewHolder.getItemViewType() : GridImageAdapter.TYPE_CAMERA;
if (itemViewType != GridImageAdapter.TYPE_CAMERA) {
if (ItemTouchHelper.ACTION_STATE_DRAG == actionState && mDragListener != null) {
mDragListener.dragState(true);
}
super.onSelectedChanged(viewHolder, actionState);
}
}
@Override
public long getAnimationDuration(@NonNull RecyclerView recyclerView, int animationType, float animateDx, float animateDy) {
needScaleSmall = true;
isUpward = true;
return super.getAnimationDuration(recyclerView, animationType, animateDx, animateDy);
}
@Override
public void clearView(@NonNull RecyclerView recyclerView, @NonNull RecyclerView.ViewHolder viewHolder) {
int itemViewType = viewHolder.getItemViewType();
if (itemViewType != GridImageAdapter.TYPE_CAMERA) {
viewHolder.itemView.setAlpha(1.0f);
super.clearView(recyclerView, viewHolder);
mAdapter.notifyDataSetChanged();
resetState();
}
}
});
不要忘记绑定
// 绑定拖拽事件
mItemTouchHelper.attachToRecyclerView(mRecyclerView);
// 注册广播
BroadcastManager.getInstance(getContext()).registerReceiver(broadcastReceiver,
BroadcastAction.ACTION_DELETE_PREVIEW_POSITION);
最后集成LuckSiege的PictureSelector2.0
private GridImageAdapter.onAddPicClickListener onAddPicClickListener = new GridImageAdapter.onAddPicClickListener() {
@Override
public void onAddPicClick() {
// 进入相册 以下是例子：不需要的api可以不写
PictureSelector.create(PublishArticle.this)
.openGallery(PictureMimeType.ofImage())// 全部.PictureMimeType.ofAll()、图片.ofImage()、视频.ofVideo()、音频.ofAudio()
.imageEngine(GlideEngine.createGlideEngine())// 外部传入图片加载引擎，必传项
.setPictureStyle(mPictureParameterStyle)// 动态自定义相册主题
.setPictureCropStyle(mCropParameterStyle)// 动态自定义裁剪主题
.maxSelectNum(maxSelectNum)// 最大图片选择数量
.minSelectNum(1)// 最小选择数量
// .isOriginalImageControl(true)
.isCompress(true)// 是否压缩
.compressQuality(20)// 图片压缩后输出质量 0~ 100
.isEnableCrop(true)// 是否裁剪
.freeStyleCropEnabled(true)// 裁剪框是否可拖拽
// .showCropFrame(true)// 是否显示裁剪矩形边框 圆形裁剪时建议设为false
.hideBottomControls(true)// 是否显示uCrop工具栏，默认不显示
.selectionData(mAdapter.getData())// 是否传入已选图片
.imageSpanCount(4)// 每行显示个数
.isReturnEmpty(false)// 未选择数据时点击按钮是否可以返回
.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED)// 设置相册Activity方向，不设置默认使用系统
.forResult(new MyResultCallback(mAdapter));
}
};
/**
* 返回结果回调
*/
private static class MyResultCallback implements OnResultCallbackListener<LocalMedia> {
private WeakReference<GridImageAdapter> mAdapterWeakReference;
public MyResultCallback(GridImageAdapter adapter) {
super();
this.mAdapterWeakReference = new WeakReference<>(adapter);
}
@Override
public void onResult(List<LocalMedia> result) {
for (LocalMedia media : result) {
Log.i(TAG, "是否压缩:" + media.isCompressed());
Log.i(TAG, "压缩:" + media.getCompressPath());
Log.i(TAG, "原图:" + media.getPath());
Log.i(TAG, "是否裁剪:" + media.isCut());
Log.i(TAG, "裁剪:" + media.getCutPath());
Log.i(TAG, "是否开启原图:" + media.isOriginal());
Log.i(TAG, "原图路径:" + media.getOriginalPath());
Log.i(TAG, "Android Q 特有Path:" + media.getAndroidQToPath());
Log.i(TAG, "宽高: " + media.getWidth() + "x" + media.getHeight());
Log.i(TAG, "Size: " + media.getSize());
//可以通过PictureSelectorExternalUtils.getExifInterface();方法获取一些额外的资源信息，如旋转角度、经纬度等信息
}
if (mAdapterWeakReference.get() != null) {
mAdapterWeakReference.get().setList(result);
mAdapterWeakReference.get().notifyDataSetChanged();
}
}
@Override
public void onCancel() {
Log.i(TAG, "PictureSelector Cancel");
}
}
再根据自己的需要进行一些回调接口的编写，就能大致实现一个可以多选图片并显示的activity了
三、问题与解决
-
在和后端的交互过程中，因为图片大小限制的原因，我们需要对图片进行一定程度的压缩。万幸的是PictureSelector自带裁剪和压缩的功能，只需要在创建时明确自己的参数，就可以实现相关的功能了。
-
拖拉功能的实现是难度比较大的。我根据的是LuckSiege的Github中所给出的demo进行修改所完成的功能，大家如果需要可以利用LuckSiege的demo进行尝试和修改。
-
对于LocalMedia类型的说明，这是LuckSiege中定义的一个文件类型，可以选择音频、视频、图片等，在这个项目中，我只使用了图片的文件类型，具体的大家可以到LuckSiege的GitHub上去查看相关说明。
四、总结
集成PictureSelector2.0并不难，难的是如何对Selector所选择的图片进行相关的操作，如排序、删除、再次添加等等，大多数新手都会面对这样的问题，我集成了Selector但是我并不知道如何去保存这些数据，如何向后端传输这些数据，这些问题，都可以通过下载demo，对demo进行分析然后再根据需要，对demo进行集成，不仅解决了主要问题，还可以学习到别人的代码。
