Android load all photos into RecyclerView,pinch to zoom by ScaleGestureDetector,kotlin(4)

客官°小女子只卖身不卖艺 2023-10-12 18:13 17阅读 0赞

## Android load all photos into RecyclerView,pinch to zoom by ScaleGestureDetector,kotlin(4) ##

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
        <uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />

import android.content.ContentValues
    import android.content.Context
    import android.net.Uri
    import android.os.Bundle
    import android.provider.MediaStore
    import android.util.Log
    import android.view.ScaleGestureDetector
    import android.view.ScaleGestureDetector.SimpleOnScaleGestureListener
    import android.view.View.OnTouchListener
    import androidx.appcompat.app.AppCompatActivity
    import androidx.recyclerview.widget.GridLayoutManager
    import androidx.recyclerview.widget.RecyclerView
    import kotlinx.coroutines.CoroutineScope
    import kotlinx.coroutines.Dispatchers
    import kotlinx.coroutines.launch
    import java.io.File
    import java.text.SimpleDateFormat
    import java.util.Date
    
    
    class MainActivity : AppCompatActivity() {
        private var mPhotos: List<Photo>? = null
        private var mRecyclerView: RecyclerView? = null
        private var mPhotoAdapter: PhotoAdapter? = null
        private var mLayoutManager: GridLayoutManager? = null
        private var mScaleGestureDetector: ScaleGestureDetector? = null
        private val TAG = "fly"
        private val ZOOM = intArrayOf(3, 5, 9)
    
        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            setContentView(R.layout.recycler_view)
            mRecyclerView = findViewById(R.id.recycler_view)
            mLayoutManager = GridLayoutManager(this, ZOOM[2])
            mLayoutManager?.orientation = GridLayoutManager.VERTICAL
            mRecyclerView?.setLayoutManager(mLayoutManager)
            mScaleGestureDetector = ScaleGestureDetector(this, object : SimpleOnScaleGestureListener() {
                override fun onScaleBegin(detector: ScaleGestureDetector): Boolean {
                    Log.d(TAG, "--onScaleBegin--")
                    return super.onScaleBegin(detector)
                }
    
                override fun onScale(detector: ScaleGestureDetector): Boolean {
                    Log.d(TAG, "--onScale--")
                    return super.onScale(detector)
                }
    
                override fun onScaleEnd(detector: ScaleGestureDetector) {
                    super.onScaleEnd(detector)
                    Log.d(TAG, "--onScaleEnd--")
                    Log.d(TAG, "TimeDelta-" + detector.timeDelta)
                    Log.d(TAG, "ScaleFactor-" + detector.scaleFactor)
                    Log.d(TAG, "currentSpan-" + detector.currentSpan)
                    scale(detector)
                }
    
                private fun scale(detector: ScaleGestureDetector): Boolean {
                    if (detector.currentSpan > 50 && detector.timeDelta > 10) {
                        val scaleFactor = detector.scaleFactor
                        val curSpanCount = mLayoutManager!!.spanCount
                        Log.d(TAG, "LayoutManager SpanCount()-\$curSpanCount")
                        val curIndex = getSpanCountIndex(curSpanCount)
                        if (scaleFactor < 1) {
                            if (curSpanCount == ZOOM[ZOOM.size - 1]) {
                                return true
                            } else {
                                mLayoutManager!!.spanCount = ZOOM[curIndex + 1]
                            }
                        } else {
                            if (curSpanCount == ZOOM[0]) {
                                return true
                            } else {
                                mLayoutManager!!.spanCount = ZOOM[curIndex - 1]
                            }
                        }
                        mRecyclerView?.setLayoutManager(mLayoutManager)
                        mPhotoAdapter?.dataChanged(mPhotos)
    
                        return true
                    }
                    return false
                }
            })
    
            mRecyclerView?.setOnTouchListener(OnTouchListener { v, event ->
                mScaleGestureDetector!!.onTouchEvent(event)
                false
            })
    
            mPhotoAdapter = PhotoAdapter(applicationContext)
            mRecyclerView?.setAdapter(mPhotoAdapter)
    
            CoroutineScope(Dispatchers.IO).launch {
                mPhotos = readAllImage(applicationContext)
                launch(Dispatchers.Main) {
                    mPhotoAdapter?.dataChanged(mPhotos)
                }
            }
        }
    
        private fun getSpanCountIndex(spanCount: Int): Int {
            var index = 0
            for (i in ZOOM.indices) {
                if (spanCount == ZOOM[i]) {
                    index = i
                }
            }
            return index
        }
    
        companion object {
            private fun readAllImage(context: Context): List<Photo> {
                val photos: MutableList<Photo> = ArrayList<Photo>()
    
                //读取手机图片
                val cursor = context.contentResolver.query(
                    MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                    null,
                    null,
                    null,
                    null
                )
                while (cursor!!.moveToNext()) {
                    //图片的路径
                    val path =
                        cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA))
    
                    //图片名称
                    val name =
                        cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DISPLAY_NAME))
    
                    //图片最后修改日期
                    val file = File(path)
                    val sdf = SimpleDateFormat("yyyy-MM-dd hh:mm:ss")
                    val date = sdf.format(Date(file.lastModified()))
    
                    //图片大小
                    val size =
                        cursor.getLong(cursor.getColumnIndexOrThrow(MediaStore.Images.Media.SIZE))
                    val photo = Photo(name, date, size, path, getImageUri(context, path))
                    photos.add(photo)
                }
                cursor.close()
                return photos
            }
    
            private fun getImageUri(context: Context, filePath: String): Uri? {
                val cursor = context.contentResolver.query(
                    MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                    arrayOf(MediaStore.Images.Media._ID),
                    MediaStore.Images.Media.DATA + "=? ",
                    arrayOf(filePath),
                    null
                )
                return if (cursor != null && cursor.moveToFirst()) {
                    val id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.MediaColumns._ID))
                    val baseUri = Uri.parse("content://media/external/images/media")
                    Uri.withAppendedPath(baseUri, "" + id)
                } else {
                    val values = ContentValues()
                    values.put(MediaStore.Images.Media.DATA, filePath)
                    context.contentResolver.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values)
                }
            }
        }
    }

import android.content.Context
    import android.view.LayoutInflater
    import android.view.View
    import android.view.ViewGroup
    import android.widget.TextView
    import androidx.recyclerview.widget.RecyclerView
    import com.github.piasy.biv.BigImageViewer
    import com.github.piasy.biv.loader.glide.GlideImageLoader
    import com.github.piasy.biv.view.BigImageView
    
    
    class PhotoAdapter(context: Context?) :
        RecyclerView.Adapter<PhotoAdapter.PhotoViewHolder>() {
        private var photos: List<Photo>? = null
    
        init {
            BigImageViewer.initialize(GlideImageLoader.with(context))
        }
    
        override fun onCreateViewHolder(
            parent: ViewGroup,
            viewType: Int
        ): PhotoViewHolder {
            val view: View =
                LayoutInflater.from(parent.context).inflate(R.layout.photo, parent, false)
            return PhotoViewHolder(view)
        }
    
        override fun onBindViewHolder(holder: PhotoViewHolder, position: Int) {
            holder.textView.text = position.toString()
            holder.imageView.showImage(photos?.get(position)?.uri)
        }
    
        override fun getItemCount(): Int {
            return photos?.size ?: 0
        }
    
        inner class PhotoViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
            var imageView: BigImageView
            var textView: TextView
    
            init {
                imageView = itemView.findViewById<BigImageView>(R.id.image)
                textView = itemView.findViewById<TextView>(R.id.text)
            }
        }
    
        fun dataChanged(photos: List<Photo>?) {
            this.photos = photos
    
            notifyDataSetChanged()
        }
    }

import android.net.Uri
    
    
    class Photo(
        //名称
        var name: String, //日期
        var date: String, //大小
        var size: Long,//路径
        var path: String,
        var uri: Uri?
    )

<?xml version="1.0" encoding="utf-8"?>
    <androidx.recyclerview.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

<?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="1dp"
        android:layout_marginTop="1dp"
        android:layout_marginRight="1dp">
    
        <com.github.piasy.biv.view.BigImageView
            android:id="@+id/image"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            app:failureImage="@android:drawable/ic_dialog_alert"
            app:failureImageInitScaleType="center"
            app:optimizeDisplay="true" />
    
        <TextView
            android:id="@+id/text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/image"
            android:layout_centerHorizontal="true"
            android:maxLines="1"
            android:text="-.-"
            android:textColor="@android:color/black" />
    </RelativeLayout>

[Android load all photos into RecyclerView,support pinch to zoom by ScaleGestureDetector,Java(3)\_zhangphil的博客-CSDN博客Android RecyclerView的StaggeredGridLayoutManager实现交错排列的子元素分组先看实现的结果如图：设计背景：现在的产品对设计的需求越来越多样化，如附录文章2是典型的联系人分组RecyclerView，子元素排列到一个相同的组，但是有些时候，UI要求把这些元素不是垂直方向的，而是像本文开头的图中所示样式排列，这就需要用StaggeredGridLayoutMa。在处理大图的浏览查看动作过程中，往往还有其他额外的事情需要处理，典型的以微信。![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/130708679][Android load all photos into RecyclerView_support pinch to zoom by ScaleGestureDetector_Java_3_zhangphil_-CSDN_Android RecyclerView_StaggeredGridLayoutManager_2_RecyclerView_UI_StaggeredGridLayoutMa_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_130708679]

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[Android load all photos into RecyclerView_support pinch to zoom by ScaleGestureDetector_Java_3_zhangphil_-CSDN_Android RecyclerView_StaggeredGridLayoutManager_2_RecyclerView_UI_StaggeredGridLayoutMa_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_130708679]: https://blog.csdn.net/zhangphil/article/details/130708679