Customize PDF view layout in Kotlin for Android

1
/*
2
 *   Copyright © 2020-2025 PSPDFKit GmbH. All rights reserved.
3
 *
4
 *   The PSPDFKit Sample applications are licensed with a modified BSD license.
5
 *   Please see License for details. This notice may not be removed from this file.
6
 */
7

8
package com.pspdfkit.catalog.examples.kotlin
9

10
import android.content.Context
11
import android.net.Uri
12
import android.os.Bundle
13
import android.view.MenuItem
14
import android.view.View
15
import androidx.annotation.UiThread
16
import androidx.core.view.GravityCompat
17
import androidx.drawerlayout.widget.DrawerLayout
18
import androidx.drawerlayout.widget.DrawerLayout.SimpleDrawerListener
19
import com.pspdfkit.catalog.R
20
import com.pspdfkit.catalog.SdkExample
21
import com.pspdfkit.catalog.tasks.ExtractAssetTask
22
import com.pspdfkit.catalog.utils.Utils
23
import com.pspdfkit.configuration.activity.PdfActivityConfiguration
24
import com.pspdfkit.configuration.activity.TabBarHidingMode
25
import com.pspdfkit.configuration.activity.ThumbnailBarMode
26
import com.pspdfkit.configuration.search.SearchType
27
import com.pspdfkit.document.PdfDocument
28
import com.pspdfkit.listeners.OnVisibilityChangedListener
29
import com.pspdfkit.ui.PdfActivity
30
import com.pspdfkit.ui.PdfActivityIntentBuilder
31
import com.pspdfkit.ui.PdfThumbnailGrid
32

33
/**
34
 * This example shows how to use a custom [PdfActivity] with a custom layout. In detail:
35
 *
36
 * - It subclasses the [PdfActivity] and uses a custom layout resource.
37
 * - It removes the thumbnail bar and adds two navigation buttons to the layouts ("Next" and "Previous").
38
 * - It puts the thumbnail grid into the right navigation drawer.
39
 */
40
class CustomLayoutExample(context: Context) : SdkExample(context, R.string.customLayoutExampleTitle, R.string.customLayoutExampleDescription) {
41
    override fun launchExample(context: Context, configuration: PdfActivityConfiguration.Builder) {
42
        // Define the custom layout of our activity inside the configuration.
43
        configuration.layout(R.layout.custom_pdf_activity)
44

45
        // The custom layout is missing some UI elements, in order to prevent the activity from
46
        // accessing them we have to deactivate them in the configuration.
47
        configuration.apply {
48
            // The custom layout has no thumbnail bar.
49
            setThumbnailBarMode(ThumbnailBarMode.THUMBNAIL_BAR_MODE_NONE)
50
            // The custom layout has no document editor.
51
            documentEditorEnabled(false)
52
            // The custom layout has no document title overlay.
53
            documentTitleOverlayEnabled(false)
54
            // The custom layout has no navigation buttons.
55
            navigationButtonsEnabled(false)
56
            // This example shows the thumbnail grid in a custom drawer layout.
57
            thumbnailGridEnabled(true)
58
            // Disable forms editing.
59
            formEditingEnabled(false)
60
            // The custom layout has no content editor.
61
            contentEditingEnabled(false)
62
            // Disable measurements
63
            setMeasurementToolsEnabled(false)
64
        }
65

66
        // Hide tab bar as it's not used by the custom layout.
67
        configuration.setTabBarHidingMode(TabBarHidingMode.HIDE)
68

69
        // We keep things simple, and use inline search and deactivate immersive mode for this example.
70
        configuration.apply {
71
            setSearchType(SearchType.INLINE)
72
            useImmersiveMode(false)
73
        }
74

75
        // We use a custom utility class to extract the example document from the assets.
76
        ExtractAssetTask.extract(WELCOME_DOC, title, context) { documentFile ->
77
            // To start the `CustomLayoutActivity` create a launch intent using the builder.
78
            val intent = PdfActivityIntentBuilder.fromUri(context, Uri.fromFile(documentFile))
79
                .configuration(configuration.build())
80
                .activityClass(CustomLayoutActivity::class)
81
                .build()
82
            context.startActivity(intent)
83
        }
84
    }
85
}
86

87
class CustomLayoutActivity : PdfActivity() {
88

89
    /**
90
     * Total number of pages in the current document.
91
     */
92
    private var documentPageCount = 0
93

94
    private lateinit var drawerLayout: DrawerLayout
95
    private lateinit var thumbnailGridView: PdfThumbnailGrid
96

97
    override fun onCreate(savedInstanceState: Bundle?) {
98
        super.onCreate(savedInstanceState)
99

100
        // Get all required views for customization.
101
        drawerLayout = findViewById(R.id.drawerLayout)
102

103
        // Dynamically set the correct width of the thumbnail grid drawer.
104
        val thumbnailGridDrawer = findViewById<View>(R.id.thumbnailGridDrawer)
105
        Utils.setProperNavigationDrawerWidth(thumbnailGridDrawer)
106

107
        thumbnailGridView = findViewById(R.id.pspdf__activity_thumbnail_grid)
108

109
        // Register the thumbnail grid with the fragment, so it is notified of page changes.
110
        requirePdfFragment().addDocumentListener(thumbnailGridView)
111

112
        // Toggle drawer when thumbnail grid visibility changes.
113
        thumbnailGridView.addOnVisibilityChangedListener(object : OnVisibilityChangedListener {
114
            override fun onShow(view: View) {
115
                drawerLayout.openDrawer(DRAWER_GRAVITY)
116
            }
117

118
            override fun onHide(view: View) {
119
                drawerLayout.closeDrawer(DRAWER_GRAVITY)
120
            }
121
        })
122

123
        // Ensure action bar and grid are visible when drawer is opened.
124
        drawerLayout.addDrawerListener(object : SimpleDrawerListener() {
125
            override fun onDrawerSlide(drawerView: View, slideOffset: Float) {}
126

127
            override fun onDrawerClosed(drawerView: View) {
128
                thumbnailGridView.hide()
129
            }
130

131
            override fun onDrawerStateChanged(newState: Int) {
132
                if (newState == DrawerLayout.STATE_DRAGGING) {
133
                    thumbnailGridView.show()
134
                }
135
            }
136
        })
137

138
        // Go to the tapped page, and close the thumbnail drawer after selecting a page.
139
        thumbnailGridView.setOnPageClickListener { _, pageIndex ->
140
            setPageIndex(pageIndex)
141
            toggleThumbnailGrid()
142
        }
143

144
        // Flip to the next page when clicking on the next page button.
145
        findViewById<View>(R.id.nextPageButton).setOnClickListener {
146
            val currentPage = pageIndex
147
            if (currentPage < documentPageCount - 1) pageIndex = currentPage + 1
148
        }
149
        // Flip to the previous page when clicking on the previous page button.
150
        findViewById<View>(R.id.previousPageButton).setOnClickListener {
151
            val currentPage = pageIndex
152
            if (currentPage > 0) pageIndex = currentPage - 1
153
        }
154
    }
155

156
    override fun onOptionsItemSelected(item: MenuItem): Boolean {
157
        when (item.itemId) {
158
            MENU_OPTION_THUMBNAIL_GRID -> {
159
                toggleThumbnailGrid()
160
                hidePSPDFViews()
161

162
                // Consume the event, preventing the default behavior.
163
                return true
164
            }
165
            MENU_OPTION_OUTLINE, MENU_OPTION_SEARCH -> {
166
                hideThumbnailGrid()
167
                // Don't consume the event here since we want to fallback to default action handling.
168
            }
169
        }
170
        return super.onOptionsItemSelected(item)
171
    }
172

173
    @Deprecated("Deprecated in Java")
174
    override fun onBackPressed() {
175
        super.onBackPressed()
176
        hideThumbnailGrid()
177
    }
178

179
    /**
180
     * Called as soon as the PDF document has been loaded.
181
     */
182
    @UiThread
183
    override fun onDocumentLoaded(document: PdfDocument) {
184
        super.onDocumentLoaded(document)
185

186
        // Retrieve the total number of pages in the document.
187
        documentPageCount = document.pageCount
188
    }
189

190
    private fun hidePSPDFViews() {
191
        pspdfKitViews.outlineView?.hide()
192
        pspdfKitViews.searchView?.hide()
193
    }
194

195
    private fun hideThumbnailGrid() {
196
        if (drawerLayout.isDrawerVisible(DRAWER_GRAVITY)) {
197
            drawerLayout.closeDrawer(DRAWER_GRAVITY)
198
        }
199
    }
200

201
    private fun toggleThumbnailGrid() {
202
        if (drawerLayout.isDrawerOpen(DRAWER_GRAVITY)) {
203
            thumbnailGridView.hide()
204
            drawerLayout.closeDrawer(DRAWER_GRAVITY)
205
        } else {
206
            thumbnailGridView.show()
207
            drawerLayout.openDrawer(DRAWER_GRAVITY)
208
        }
209
    }
210

211
    companion object {
212
        /** Gravity of the thumbnail grid drawer. */
213
        private const val DRAWER_GRAVITY = GravityCompat.END
214
    }
215
}