添加搜索文字功能（基本完成），还可优化。

app/src/main/java/com/all/pdfreader/pro/app/ui/act/PdfViewActivity.kt

@@ -3,13 +3,19 @@ package com.all.pdfreader.pro.app.ui.act
 import android.content.Context
 import android.content.Intent
 import android.os.Bundle
+import android.text.Editable
+import android.text.TextWatcher
 import android.view.MotionEvent
 import android.view.View
+import android.view.inputmethod.EditorInfo
+import android.widget.Toast
+import androidx.activity.OnBackPressedCallback
 import androidx.lifecycle.ViewModelProvider
 import androidx.lifecycle.lifecycleScope
 import com.all.pdfreader.pro.app.R
 import com.all.pdfreader.pro.app.databinding.ActivityPdfViewBinding
 import com.all.pdfreader.pro.app.model.FileActionEvent
+import com.all.pdfreader.pro.app.model.PdfPickerSource
 import com.all.pdfreader.pro.app.room.entity.PdfDocumentEntity
 import com.all.pdfreader.pro.app.ui.dialog.BookmarksDialogFragment
 import com.all.pdfreader.pro.app.ui.dialog.ListMoreDialogFragment
@@ -17,7 +23,11 @@ import com.all.pdfreader.pro.app.ui.dialog.PdfPasswordProtectionDialogFragment
 import com.all.pdfreader.pro.app.ui.dialog.ViewModelDialogFragment
 import com.all.pdfreader.pro.app.ui.view.CustomScrollHandle
 import com.all.pdfreader.pro.app.util.AppUtils
+import com.all.pdfreader.pro.app.util.AppUtils.hideKeyboard
+import com.all.pdfreader.pro.app.util.AppUtils.showKeyboard
 import com.all.pdfreader.pro.app.util.FileUtils
+import com.all.pdfreader.pro.app.util.PDFHighlighter
+import com.all.pdfreader.pro.app.util.PDFSearchManager
 import com.all.pdfreader.pro.app.viewmodel.PdfViewModel
 import com.all.pdfreader.pro.app.viewmodel.observeEvent
 import com.github.barteksc.pdfviewer.listener.OnErrorListener
@@ -26,7 +36,13 @@ import com.github.barteksc.pdfviewer.listener.OnPageChangeListener
 import com.github.barteksc.pdfviewer.listener.OnTapListener
 import com.gyf.immersionbar.BarHide
 import com.gyf.immersionbar.ImmersionBar
+import com.tom_roush.pdfbox.pdmodel.PDDocument
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
 import java.io.File
 
 class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeListener,
@@ -51,6 +67,10 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
     private val repository = getRepository()
     private var isFullScreen = false
     private var lastLoadedFilePath: String? = null
+    private var showSearchTextView = false
+    private lateinit var searchManager: PDFSearchManager
+    private lateinit var highlighter: PDFHighlighter
+    private var pageCheckJob: Job? = null
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
@@ -58,6 +78,7 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
         setContentView(binding.root)
         ImmersionBar.with(this).statusBarView(binding.view).statusBarDarkFont(true)
             .navigationBarColor(R.color.white).init()
+        setupDoubleBackExit()
         initObserve()
         val filePath = intent.getStringExtra(EXTRA_PDF_HASH)
             ?: throw IllegalArgumentException("PDF file hash is required")
@@ -165,7 +186,7 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
 
     private fun setupOnClick() {
         binding.backBtn.setOnClickListener {
-            finish()
+            onBackPressedDispatcher.onBackPressed()
         }
         binding.eyeCareOverlayBtn.setOnClickListener {
             appStore.isEyeCareMode = !appStore.isEyeCareMode
@@ -188,6 +209,55 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
         binding.moreBtn.setOnClickListener {
             ListMoreDialogFragment(pdfDocument.filePath).show(supportFragmentManager, FRAG_TAG)
         }
+        binding.searchTextBtn.setOnClickListener {
+            showSearchTextView = true
+            updateSearchState(true)
+            binding.selectNextBtn.visibility = View.GONE
+            binding.selectPreviousBtn.visibility = View.GONE
+        }
+        binding.searchEdit.addTextChangedListener(object : TextWatcher {
+            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}
+            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {}
+            override fun afterTextChanged(s: Editable?) {
+                val query = s?.toString().orEmpty()
+                binding.deleteIv.visibility = if (query.isEmpty()) View.GONE else View.VISIBLE
+                binding.searchIv.visibility = if (query.isEmpty()) View.VISIBLE else View.GONE
+            }
+        })
+        binding.searchEdit.setOnEditorActionListener { _, actionId, _ ->
+            if (actionId == EditorInfo.IME_ACTION_SEARCH) {
+                val searchText = binding.searchEdit.text.toString().trim()
+                if (searchText.isNotEmpty()) {
+                    performSearch(searchText)
+                    binding.searchEdit.hideKeyboard()  // 收起键盘
+                } else {
+                    showToast(getString(R.string.enter_search_key))
+                }
+                true
+            } else {
+                false
+            }
+        }
+        binding.deleteIv.setOnClickListener {
+            binding.searchEdit.apply {
+                setText("")
+                clearComposingText()
+                setSelection(0)
+            }
+            clearHighlights()
+            binding.selectNextBtn.visibility = View.GONE
+            binding.selectPreviousBtn.visibility = View.GONE
+        }
+        binding.selectNextBtn.setOnClickListener {
+            highlighter.selectNext { id ->
+                showToast(getString(id))
+            }
+        }
+        binding.selectPreviousBtn.setOnClickListener {
+            highlighter.selectPrevious { id ->
+                showToast(getString(id))
+            }
+        }
     }
 
     private fun loadPdf() {
@@ -199,6 +269,7 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
             finish()
             return
         }
+        setupPDFSearchManager()//初始化搜索文本需要的类
         if (pdfDocument.isPassword) {
             showPasswordDialog(file)
         } else {
@@ -239,10 +310,22 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
             lastReadPage = page, readingProgress = (page.toFloat() / pageCount.toFloat()) * 100
         )
         saveReadingProgress()
-    }
 
-    override fun onDestroy() {
+        val doc = searchManager.getCachedDoc() ?: return
-        super.onDestroy()
+        // 取消上一次检查任务
+        pageCheckJob?.cancel()
+        // 启动新的防抖任务
+        pageCheckJob = lifecycleScope.launch(Dispatchers.IO) {
+            delay(120) // 防抖 120ms
+            val hasText = checkPageHasText(doc, page)
+            if (hasText && searchManager.hasSearched && !searchManager.currentSearchText.isNullOrEmpty()) {
+                searchTextIng(
+                    File(pdfDocument.filePath),
+                    searchManager.currentSearchText ?: "",
+                    binding.pdfview.currentPage
+                )
+            }
+        }
     }
 
     private fun saveReadingProgress() {
@@ -276,9 +359,7 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
             onTap(this@PdfViewActivity) // 单击回调
             onPageChange(this@PdfViewActivity) // 页面改变回调
             scrollHandle(CustomScrollHandle(this@PdfViewActivity)) // 自定义的页数展示
-            onDraw { canvas, pageWidth, pageHeight, displayedPage ->
+            onDraw(highlighter)
-
-            }
             if (appStore.isPageFling) {
                 pageSnap(true)//页面可在逐页中，可居中展示，非逐页模式，滑动停止后可自动定格在居中位置。
                 pageFling(true)//逐页
@@ -299,6 +380,9 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
     }
 
     private fun toggleFullScreen() {
+        if (showSearchTextView) {//如果是搜索文本时，不全屏
+            return
+        }
         isFullScreen = !isFullScreen
         updateStatusAndNavigationLayout(isFullScreen)
         if (isFullScreen) {
@@ -337,4 +421,129 @@ class PdfViewActivity : BaseActivity(), OnLoadCompleteListener, OnPageChangeList
         ImmersionBar.with(this).statusBarView(binding.view).statusBarDarkFont(true)
             .navigationBarColor(navColor).init()
     }
+
+    private fun setupDoubleBackExit() {
+        onBackPressedDispatcher.addCallback(this, object : OnBackPressedCallback(true) {
+            override fun handleOnBackPressed() {
+                if (showSearchTextView) {//如果当前是搜索，则退出搜索
+                    showSearchTextView = false
+                    updateSearchState(false)
+                    clearHighlights()
+                    binding.searchEdit.apply {
+                        setText("")
+                        clearComposingText()
+                        setSelection(0)
+                    }
+                } else {
+                    isEnabled = false // 解除拦截
+                    onBackPressedDispatcher.onBackPressed() // 调用系统默认返回逻辑
+                }
+            }
+        })
+    }
+
+    private fun updateSearchState(b: Boolean) {
+        if (b) {
+            binding.searchTextLayout.visibility = View.VISIBLE
+            binding.navigationLayout.visibility = View.GONE
+            binding.searchEdit.showKeyboard()
+        } else {
+            binding.searchTextLayout.visibility = View.GONE
+            binding.navigationLayout.visibility = View.VISIBLE
+            binding.searchEdit.hideKeyboard()
+        }
+    }
+
+    private fun setupPDFSearchManager() {
+        searchManager = PDFSearchManager(binding.pdfview)
+        highlighter = PDFHighlighter(binding.pdfview, searchManager)
+
+        initSearchDocument()
+    }
+
+    private fun initSearchDocument() {
+        val file = File(pdfDocument.filePath)
+        lifecycleScope.launch(Dispatchers.IO) {
+            searchManager.getDocument(file, onLoaded = { doc ->
+                lifecycleScope.launch(Dispatchers.IO) {
+                    checkPageHasText(doc, binding.pdfview.currentPage)
+                }
+            }, onError = { e ->
+                runOnUiThread {
+                    binding.searchTextBtn.visibility = View.GONE
+                    binding.searchTextBtn.isEnabled = false
+                }
+            })
+        }
+    }
+
+    /**
+     * 异步检查指定页是否有文字并更新按钮
+     */
+    private suspend fun checkPageHasText(doc: PDDocument, pageIndex: Int): Boolean {
+        val hasText = searchManager.pageHasText(doc, pageIndex, minChars = 10) // 可调整阈值
+        withContext(Dispatchers.Main) {
+            if (hasText) {
+                binding.searchTextBtn.visibility = View.VISIBLE
+                binding.searchTextBtn.isEnabled = true
+            } else {
+                binding.searchTextBtn.visibility = View.GONE
+                binding.searchTextBtn.isEnabled = false
+            }
+        }
+        return hasText
+    }
+
+    private fun performSearch(searchText: String) {
+        val file = File(pdfDocument.filePath)
+        lifecycleScope.launch(Dispatchers.IO) {
+            searchTextIng(file, searchText, binding.pdfview.currentPage)
+        }
+    }
+
+    private fun searchTextIng(pdfFile: File, key: String, targetPage: Int? = null) {
+        lifecycleScope.launch(Dispatchers.IO) {
+            try {
+                val results = searchManager.searchText(pdfFile, key, targetPage)
+
+                withContext(Dispatchers.Main) {
+                    if (!results.isEmpty()) {
+                        binding.selectNextBtn.visibility = View.VISIBLE
+                        binding.selectPreviousBtn.visibility = View.VISIBLE
+                        results.firstOrNull()?.let { firstResult ->
+                            onSearchResultClicked(firstResult)
+                        }
+                    }
+                }
+            } catch (e: Exception) {
+                e.printStackTrace()
+            }
+        }
+    }
+
+    private fun onSearchResultClicked(
+        result: PDFSearchManager.TextSearchResult, isJumpTo: Boolean = false
+    ) {
+        if (isJumpTo) {
+            // 跳转到对应页面 (PDFView 页面索引从0开始)
+            binding.pdfview.jumpTo(result.pageNumber - 1)
+        }
+
+        // 设置高亮
+        highlighter.setCurrentPageHighlights(result.pageNumber)
+        // 标记已搜索高亮
+        searchManager.currentSearchText = result.text
+        searchManager.hasSearched = true
+    }
+
+    private fun clearHighlights() {
+        searchManager.clearHighlights()
+        highlighter.clearCurrentHighlights()
+    }
+
+    override fun onDestroy() {
+        super.onDestroy()
+        searchManager.closeCachedDocument()
+    }
+
 }

app/src/main/java/com/all/pdfreader/pro/app/util/AppUtils.kt

@@ -100,6 +100,15 @@ object AppUtils {
         }, 200)
     }
 
+    fun EditText.hideKeyboard() {
+        clearFocus()
+        postDelayed({
+            val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as? InputMethodManager
+            imm?.hideSoftInputFromWindow(windowToken, 0)
+        }, 200)
+
+    }
+
     /**
      * 分享文件（自动识别 MIME 类型）
      * @param context 上下文

app/src/main/java/com/all/pdfreader/pro/app/util/PDFHighlighter.kt

@@ -3,6 +3,7 @@ package com.all.pdfreader.pro.app.util
 import android.graphics.Canvas
 import android.graphics.Paint
 import android.graphics.RectF
+import com.all.pdfreader.pro.app.R
 import com.github.barteksc.pdfviewer.PDFView
 import com.github.barteksc.pdfviewer.listener.OnDrawListener
 
@@ -11,6 +12,13 @@ class PDFHighlighter(
     private val searchManager: PDFSearchManager
 ) : OnDrawListener {
 
+    enum class ClickType {
+        NEXT,
+        PREVIOUS
+    }
+
+    private var type = ClickType.NEXT
+
     private val highlightPaint = Paint().apply {
         color = 0x80FFD700.toInt() // 半透明黄色
         style = Paint.Style.FILL
@@ -22,13 +30,34 @@ class PDFHighlighter(
         strokeWidth = 2f
     }
 
+    private val selectedPaint = Paint().apply {
+        color = 0x80FF4500.toInt() // 当前选中高亮，橙红色半透明
+        style = Paint.Style.FILL
+    }
+
+    private val selectedStrokePaint = Paint().apply {
+        color = 0xFFFF6347.toInt() // 当前选中边框，亮橙红
+        style = Paint.Style.STROKE
+        strokeWidth = 2f
+    }
+
     private var currentPageHighlights: List<PDFSearchManager.TextPositionInfo> = emptyList()
+    private var currentSelectedIndex: Int = -1
 
     /**
      * 设置当前页面的高亮
      */
     fun setCurrentPageHighlights(page: Int) {
         currentPageHighlights = searchManager.getHighlightsForPage(page)
+        currentSelectedIndex = when (type) {
+            ClickType.NEXT -> {
+                if (currentPageHighlights.isNotEmpty()) 0 else -1
+            }
+
+            ClickType.PREVIOUS -> {
+                if (currentPageHighlights.isNotEmpty()) currentPageHighlights.size - 1 else -1
+            }
+        }
         pdfView.invalidate()
     }
 
@@ -37,18 +66,78 @@ class PDFHighlighter(
      */
     fun clearCurrentHighlights() {
         currentPageHighlights = emptyList()
+        currentSelectedIndex = -1
         pdfView.invalidate()
     }
 
-    override fun onLayerDrawn(canvas: Canvas, pageWidth: Float, pageHeight: Float, displayedPage: Int) {
+    /**
-        // 只绘制当前显示页面的高亮
+     * 选中下一条高亮
+     */
+    fun selectNext(rid: ((Int) -> Unit)? = null) {
+        type = ClickType.NEXT
+        if (currentPageHighlights.isEmpty()) {//当前页没有对应的文字，直接跳转下一页
+            val nextPage = searchManager.currentHighlightPage + 1
+            pdfView.jumpTo(nextPage, true)
+            return
+        }
+        if (currentSelectedIndex < currentPageHighlights.size - 1) {
+            currentSelectedIndex++
+            //下一页+，需要刷新
+            pdfView.invalidate()
+        } else {
+            // 当前页最后一条，尝试跳到下一页
+            val nextPage = searchManager.currentHighlightPage + 1
+            if (nextPage < pdfView.pageCount) {
+                pdfView.jumpTo(nextPage, true)
+                currentSelectedIndex = 0
+            } else {
+                rid?.invoke(R.string.no_more_results)
+            }
+        }
+    }
+
+    /**
+     * 选中上一条高亮
+     */
+    fun selectPrevious(rid: ((Int) -> Unit)? = null) {
+        type = ClickType.PREVIOUS
+        if (currentPageHighlights.isEmpty()) { // 当前页没有对应的文字，直接跳转上一页
+            val prevPage = searchManager.currentHighlightPage - 1
+            if (prevPage >= 0) {
+                pdfView.jumpTo(prevPage, true)
+            } else {
+                rid?.invoke(R.string.no_more_results)
+            }
+            return
+        } 
+        if (currentSelectedIndex > 0) {
+            currentSelectedIndex--
+            pdfView.invalidate()
+        } else {
+            val prevPage = searchManager.currentHighlightPage - 1
+            if (prevPage >= 0) {
+                pdfView.jumpTo(prevPage, true)
+                currentPageHighlights = emptyList()
+                currentSelectedIndex = -1
+            } else {
+                rid?.invoke(R.string.no_more_results)
+            }
+        }
+    }
+
+
+    override fun onLayerDrawn(
+        canvas: Canvas,
+        pageWidth: Float,
+        pageHeight: Float,
+        displayedPage: Int
+    ) {
         if (displayedPage != searchManager.currentHighlightPage) {
             searchManager.currentHighlightPage = displayedPage
-            setCurrentPageHighlights(displayedPage + 1) // PDFView 页面从0开始，我们的搜索从1开始
+//            setCurrentPageHighlights(displayedPage + 1)
         }
 
-        // 绘制高亮区域
+        currentPageHighlights.forEachIndexed { index, position ->
-        currentPageHighlights.forEach { position ->
             try {
                 val rect = position.getRelativeRect()
                 val absoluteRect = RectF(
@@ -58,7 +147,6 @@ class PDFHighlighter(
                     rect.bottom * pageHeight
                 )
 
-                // 可选：添加小的边距让高亮更明显
                 val margin = 1f
                 val paddedRect = RectF(
                     absoluteRect.left - margin,
@@ -67,12 +155,13 @@ class PDFHighlighter(
                     absoluteRect.bottom + margin
                 )
 
-                // 绘制半透明高亮
+                if (index == currentSelectedIndex) {
-                canvas.drawRect(paddedRect, highlightPaint)
+                    canvas.drawRect(paddedRect, selectedPaint)
-
+                    canvas.drawRect(paddedRect, selectedStrokePaint)
-                // 绘制边框
+                } else {
-                canvas.drawRect(paddedRect, highlightStrokePaint)
+                    canvas.drawRect(paddedRect, highlightPaint)
-
+                    canvas.drawRect(paddedRect, highlightStrokePaint)
+                }
             } catch (e: Exception) {
                 e.printStackTrace()
             }

app/src/main/java/com/all/pdfreader/pro/app/util/PDFSearchManager.kt

@@ -198,49 +198,74 @@ class PDFSearchManager(private val pdfView: PDFView) {
         )
     }
 
+    /**
+     * 在一页的 TextPositionInfo 列表中搜索指定文本，并返回每个匹配的高亮区域。
+     *
+     * 逻辑说明：
+     * 1. 按视觉顺序（纵向 y, 横向 x）排序字符。
+     * 2. 根据 y 坐标将字符分组为“同一行”，避免跨行高亮。
+     * 3. 对每一行独立进行逐字符匹配：
+     *    - 清理不可打印字符（零宽空格、控制字符等）。
+     *    - 如果匹配成功，则将匹配字符合并为一个矩形区域。
+     *
+     * @param positions 当前页的所有字符位置信息（TextPositionInfo）。
+     * @param searchText 要搜索的文本（不区分大小写）。
+     * @return 匹配的高亮区域列表，每个 TextPositionInfo 对象表示一段匹配文字。
+     */
     private fun findTextMatches(
         positions: List<TextPositionInfo>,
         searchText: String
     ): List<TextPositionInfo> {
         val matches = mutableListOf<TextPositionInfo>()
-        val fullText = positions.joinToString("") { it.text }.toLowerCase()
+        val chars = searchText.lowercase().toCharArray()
 
-        var index = 0
+        // 按纵向 y、横向 x 排序，保证字符视觉顺序
-        while (index < fullText.length) {
+        val sortedPositions = positions.sortedWith(compareBy({ it.y }, { it.x }))
-            val matchIndex = fullText.indexOf(searchText, index)
-            if (matchIndex == -1) break
 
-            // 精确查找匹配的文本段在positions中的范围
+        // 按行拆分字符，避免高亮跨行
-            var currentLength = 0
+        val lines = mutableListOf<MutableList<TextPositionInfo>>()
-            val matchedPositions = mutableListOf<TextPositionInfo>()
+        var currentLine = mutableListOf<TextPositionInfo>()
+        var lastY = sortedPositions.firstOrNull()?.y ?: 0f
+        val lineThreshold = 2f // y 差值小于阈值则视为同一行，可根据字体大小微调
 
-            for (pos in positions) {
+        for (pos in sortedPositions) {
-                val positionStart = currentLength
+            if (currentLine.isNotEmpty() && kotlin.math.abs(pos.y - lastY) > lineThreshold) {
-                val positionEnd = currentLength + pos.text.length
+                // y 坐标变化超过阈值，说明换行
+                lines.add(currentLine)
+                currentLine = mutableListOf()
+            }
+            currentLine.add(pos)
+            lastY = pos.y
+        }
+        if (currentLine.isNotEmpty()) lines.add(currentLine)
 
-                // 精确检查：这个位置是否在当前匹配范围内
+        // 对每一行独立匹配搜索文本
-                if (positionStart < matchIndex + searchText.length &&
+        for (line in lines) {
-                    positionEnd > matchIndex
+            var i = 0
-                ) {
+            while (i <= line.size - chars.size) {
-                    matchedPositions.add(pos)
+                var matched = true
+                val matchedPositions = mutableListOf<TextPositionInfo>()
+
+                for (j in chars.indices) {
+                    // 清理不可打印字符（零宽空格、控制字符等）
+                    val posChar = line[i + j].text.replace(Regex("\\p{C}"), "").lowercase()
+                    if (posChar != chars[j].toString()) {
+                        matched = false
+                        break
+                    }
+                    matchedPositions.add(line[i + j])
                 }
 
-                currentLength += pos.text.length
+                if (matched) {
-
+                    // 合并匹配字符为矩形区域
-                // 如果已经超过当前匹配范围，立即停止
+                    matches.add(mergePositions(matchedPositions, searchText))
-                if (currentLength >= matchIndex + searchText.length) break
+                    i += chars.size
+                } else {
+                    i++
+                }
             }
-
-            // 计算合并后的矩形区域
-            if (matchedPositions.isNotEmpty()) {
-                val mergedPosition = mergePositions(matchedPositions, searchText)
-                matches.add(mergedPosition)
-            }
-
-            index = matchIndex + searchText.length
         }
 
-        Log.d("PDF_DEBUG", "找到 ${matches.size} 个独立匹配")
         return matches
     }
 
@@ -297,10 +322,6 @@ class PDFSearchManager(private val pdfView: PDFView) {
 
         val stripper = object : PDFTextStripper() {
             override fun processTextPosition(text: TextPosition) {
-                Log.d(
-                    "ocean",
-                    "processTextPosition text->$text  width->${text.width}height->${text.height}"
-                )
                 //太小的文字当没有
                 if (text.width > 1 && text.height > 2) {
                     charCount++

app/src/main/res/drawable/arrow_next_icon.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="256dp"
+    android:height="256dp"
+    android:viewportWidth="1024"
+    android:viewportHeight="1024">
+  <path
+      android:pathData="M333.1,126.5l-0.7,0.7c-12.3,12.3 -12.3,32.4 0,44.7l339.9,339.9 -340.1,340.1c-12.5,12.5 -12.5,32.9 0,45.4s32.9,12.5 45.4,0L740,535s0.1,-0.1 0.2,-0.1l0.7,-0.7c12.3,-12.3 12.3,-32.4 0,-44.7l-363,-363c-12.4,-12.3 -32.5,-12.3 -44.8,0z"
+      android:fillColor="#000000"/>
+</vector>

app/src/main/res/drawable/arrow_previous_icon.xml

@@ -0,0 +1,9 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="256dp"
+    android:height="256dp"
+    android:viewportWidth="1024"
+    android:viewportHeight="1024">
+  <path
+      android:pathData="M690.8,126.5l0.7,0.7c12.3,12.3 12.3,32.4 0,44.7l-340,340L691.6,852c12.5,12.5 12.5,32.9 0,45.4s-32.9,12.5 -45.4,0L283.9,535s-0.1,-0.1 -0.2,-0.1l-0.7,-0.7c-12.3,-12.3 -12.3,-32.4 0,-44.7l363,-363c12.4,-12.3 32.5,-12.3 44.8,0z"
+      android:fillColor="#000000"/>
+</vector>

app/src/main/res/drawable/dr_item_img_frame.xml

@@ -2,6 +2,6 @@
 <shape xmlns:android="http://schemas.android.com/apk/res/android"
     android:shape="rectangle">
     <stroke android:color="@color/line_color"
-        android:width="0.5dp"/>
+        android:width="1dp"/>
     <corners android:radius="8dp" />
 </shape>

app/src/main/res/layout/activity_pdf_view.xml

@@ -42,47 +42,87 @@
             <LinearLayout
                 android:id="@+id/searchTextLayout"
                 android:layout_width="match_parent"
-                android:layout_height="wrap_content"
+                android:layout_height="match_parent"
-                android:layout_marginEnd="16dp"
-                android:background="@drawable/dr_item_img_frame"
                 android:gravity="center_vertical"
+                android:orientation="horizontal"
                 android:visibility="gone">
 
-                <com.google.android.material.textfield.TextInputEditText
+                <LinearLayout
-                    android:id="@+id/searchEdit"
-                    style="@style/TextViewFont_PopRegular"
                     android:layout_width="0dp"
                     android:layout_height="wrap_content"
-                    android:layout_margin="8dp"
+                    android:layout_marginEnd="16dp"
                     android:layout_weight="1"
-                    android:background="@null"
+                    android:background="@drawable/dr_item_img_frame"
-                    android:hint="@string/search_hint"
+                    android:gravity="center_vertical">
-                    android:textSize="14sp" />
+
+                    <com.google.android.material.textfield.TextInputEditText
+                        android:id="@+id/searchEdit"
+                        style="@style/TextViewFont_PopRegular"
+                        android:layout_width="0dp"
+                        android:layout_height="wrap_content"
+                        android:layout_margin="8dp"
+                        android:layout_weight="1"
+                        android:background="@null"
+                        android:hint="@string/search_hint"
+                        android:imeOptions="actionSearch"
+                        android:inputType="text"
+                        android:maxLines="1"
+                        android:textSize="14sp" />
 
 
-                <RelativeLayout
+                    <RelativeLayout
-                    android:layout_width="wrap_content"
-                    android:layout_height="wrap_content"
-                    android:layout_marginStart="12dp"
-                    android:layout_marginEnd="12dp">
-
-                    <ImageView
-                        android:id="@+id/searchIv"
                         android:layout_width="wrap_content"
                         android:layout_height="wrap_content"
-                        android:src="@drawable/search" />
+                        android:layout_marginStart="12dp"
+                        android:layout_marginEnd="12dp">
+
+                        <ImageView
+                            android:id="@+id/searchIv"
+                            android:layout_width="wrap_content"
+                            android:layout_height="wrap_content"
+                            android:src="@drawable/search" />
+
+                        <ImageView
+                            android:id="@+id/deleteIv"
+                            android:layout_width="wrap_content"
+                            android:layout_height="wrap_content"
+                            android:src="@drawable/delete_cha_icon"
+                            android:visibility="gone" />
+
+                    </RelativeLayout>
+                </LinearLayout>
+
+                <LinearLayout
+                    android:id="@+id/selectPreviousBtn"
+                    android:layout_width="32dp"
+                    android:layout_height="32dp"
+                    android:background="@drawable/dr_click_effect_oval_transparent"
+                    android:gravity="center">
 
                     <ImageView
-                        android:id="@+id/deleteIv"
+                        android:layout_width="24dp"
-                        android:layout_width="wrap_content"
+                        android:layout_height="24dp"
-                        android:layout_height="wrap_content"
+                        android:src="@drawable/arrow_previous_icon" />
-                        android:src="@drawable/delete_cha_icon"
+
-                        android:visibility="gone" />
+                </LinearLayout>
+
+                <LinearLayout
+                    android:id="@+id/selectNextBtn"
+                    android:layout_width="32dp"
+                    android:layout_height="32dp"
+                    android:background="@drawable/dr_click_effect_oval_transparent"
+                    android:layout_marginEnd="16dp"
+                    android:gravity="center">
+
+                    <ImageView
+                        android:layout_width="24dp"
+                        android:layout_height="24dp"
+                        android:src="@drawable/arrow_next_icon" />
+
+                </LinearLayout>
 
-                </RelativeLayout>
             </LinearLayout>
 
-
             <LinearLayout
                 android:layout_width="match_parent"
                 android:layout_height="match_parent"
@@ -109,7 +149,7 @@
                     android:layout_marginStart="8dp"
                     android:background="@drawable/dr_click_effect_oval_transparent"
                     android:gravity="center"
-                    android:visibility="gone">
+                    android:visibility="visible">
 
                     <ImageView
                         android:layout_width="24dp"

app/src/main/res/values/strings.xml

@@ -163,4 +163,6 @@
     <string name="no_app_to_open_image">No app found to open image</string>
     <string name="failed_to_open_image">Failed to open image</string>
     <string name="press_again_to_exit">Press again to exit</string>
+    <string name="enter_search_key">Please enter the search keyword</string>
+    <string name="no_more_results">No more results</string>
 </resources>