Show and hide the keyboard when navigating to and from the EditFragment

app/build.gradle

@@ -29,7 +29,7 @@ android {
         exclude 'META-INF/LICENSE'
         exclude 'META-INF/DEPENDENCIES'
     }
-    compileSdkVersion 28
+    compileSdkVersion 29
     buildToolsVersion '28.0.3'
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8
@@ -38,7 +38,7 @@ android {
     defaultConfig {
         applicationId "com.wbrawner.simplemarkdown"
         minSdkVersion 21
-        targetSdkVersion 28
+        targetSdkVersion 29
         multiDexEnabled true
         versionCode 20
         versionName "0.7.0"
@@ -64,7 +64,6 @@ android {
             buildConfigField "boolean", "ENABLE_CUSTOM_CSS", "false"
         }
     }
-    flavorDimensions "platform"
     dexOptions {
         jumboMode true
     }
@@ -83,11 +82,11 @@ dependencies {
     androidTestImplementation('androidx.test.espresso:espresso-core:3.1.0', {
         exclude group: 'com.android.support', module: 'support-annotations'
     })
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
-    androidTestImplementation 'androidx.test:runner:1.1.1'
+    androidTestImplementation 'androidx.test:runner:1.2.0'
-    androidTestImplementation 'androidx.test:rules:1.1.1'
+    androidTestImplementation 'androidx.test:rules:1.2.0'
     androidTestImplementation 'androidx.test.uiautomator:uiautomator:2.2.0'
-    implementation 'androidx.appcompat:appcompat:1.1.0-alpha05'
+    implementation 'androidx.appcompat:appcompat:1.1.0-rc01'
     implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
     implementation 'com.google.android.material:material:1.0.0'
     implementation 'androidx.legacy:legacy-support-v13:1.0.0'
@@ -100,9 +99,9 @@ dependencies {
     implementation 'com.jakewharton.rxbinding2:rxbinding-design:2.0.0'
     implementation 'io.reactivex.rxjava2:rxandroid:2.1.1'
     implementation 'io.reactivex.rxjava2:rxjava:2.2.7'
-    implementation 'com.google.firebase:firebase-core:16.0.9'
+    implementation 'com.google.firebase:firebase-core:17.0.1'
     implementation 'com.android.billingclient:billing:1.2'
-    implementation 'com.crashlytics.sdk.android:crashlytics:2.10.0'
+    implementation 'com.crashlytics.sdk.android:crashlytics:2.10.1'
     implementation 'androidx.multidex:multidex:2.0.1'
     implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version"
     implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"

app/src/main/java/com/wbrawner/simplemarkdown/utility/Extensions.kt

@@ -0,0 +1,13 @@
+package com.wbrawner.simplemarkdown.utility
+
+import android.content.Context
+import android.view.View
+import android.view.inputmethod.InputMethodManager
+
+fun View.showKeyboard() =
+        (context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager)
+                .toggleSoftInput(InputMethodManager.SHOW_FORCED, 0)
+
+fun View.hideKeyboard() =
+        (context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager)
+                .hideSoftInputFromWindow(windowToken, 0)

app/src/main/java/com/wbrawner/simplemarkdown/view/ViewPagerPage.kt

@@ -0,0 +1,6 @@
+package com.wbrawner.simplemarkdown.view
+
+interface ViewPagerPage {
+    fun onSelected()
+    fun onDeselected()
+}

app/src/main/java/com/wbrawner/simplemarkdown/view/activity/MainActivity.kt

@@ -50,7 +50,9 @@ class MainActivity : AppCompatActivity(), ActivityCompat.OnRequestPermissionsRes
                     )
         }
         (application as MarkdownApplication).component.inject(this)
-        pager.adapter = EditPagerAdapter(supportFragmentManager, this@MainActivity)
+        val adapter = EditPagerAdapter(supportFragmentManager, this@MainActivity)
+        pager.adapter = adapter
+        pager.addOnPageChangeListener(adapter)
         pager.pageMargin = 1
         pager.setPageMarginDrawable(R.color.colorAccent)
         tabLayout.setupWithViewPager(pager)

app/src/main/java/com/wbrawner/simplemarkdown/view/adapter/EditPagerAdapter.kt

@@ -5,16 +5,21 @@ import android.content.res.Configuration
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.FragmentManager
 import androidx.fragment.app.FragmentPagerAdapter
+import androidx.viewpager.widget.ViewPager
 import com.wbrawner.simplemarkdown.R
 import com.wbrawner.simplemarkdown.view.fragment.EditFragment
 import com.wbrawner.simplemarkdown.view.fragment.PreviewFragment
 
-class EditPagerAdapter(fm: FragmentManager, private val context: Context) : FragmentPagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {
+class EditPagerAdapter(fm: FragmentManager, private val context: Context)
+    : FragmentPagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT), ViewPager.OnPageChangeListener {
+
+    private val editFragment = EditFragment()
+    private val previewFragment = PreviewFragment()
 
     override fun getItem(position: Int): Fragment {
         return when (position) {
-            FRAGMENT_EDIT -> EditFragment()
+            FRAGMENT_EDIT -> editFragment
-            FRAGMENT_PREVIEW -> PreviewFragment()
+            FRAGMENT_PREVIEW -> previewFragment
             else -> throw IllegalStateException("Attempting to get fragment for invalid page number")
         }
     }
@@ -40,6 +45,23 @@ class EditPagerAdapter(fm: FragmentManager, private val context: Context) : Frag
         }
     }
 
+    override fun onPageScrollStateChanged(state: Int) {
+    }
+
+    override fun onPageScrolled(position: Int, positionOffset: Float, positionOffsetPixels: Int) {
+    }
+
+    override fun onPageSelected(position: Int) {
+        when (position) {
+            FRAGMENT_EDIT -> {
+                editFragment.onSelected()
+            }
+            FRAGMENT_PREVIEW -> {
+                editFragment.onDeselected()
+            }
+        }
+    }
+
     companion object {
         const val FRAGMENT_EDIT = 0
         const val FRAGMENT_PREVIEW = 1

app/src/main/java/com/wbrawner/simplemarkdown/view/fragment/EditFragment.kt

@@ -1,14 +1,12 @@
 package com.wbrawner.simplemarkdown.view.fragment
 
 import android.annotation.SuppressLint
-import android.content.Context
 import android.os.Bundle
 import android.preference.PreferenceManager
 import android.view.LayoutInflater
 import android.view.MotionEvent
 import android.view.View
 import android.view.ViewGroup
-import android.view.inputmethod.InputMethodManager
 import android.widget.EditText
 import android.widget.ScrollView
 import android.widget.Toast
@@ -19,20 +17,22 @@ import com.wbrawner.simplemarkdown.R
 import com.wbrawner.simplemarkdown.presentation.MarkdownPresenter
 import com.wbrawner.simplemarkdown.utility.MarkdownObserver
 import com.wbrawner.simplemarkdown.utility.ReadabilityObserver
+import com.wbrawner.simplemarkdown.utility.hideKeyboard
+import com.wbrawner.simplemarkdown.utility.showKeyboard
 import com.wbrawner.simplemarkdown.view.MarkdownEditView
+import com.wbrawner.simplemarkdown.view.ViewPagerPage
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.schedulers.Schedulers
 import java.util.concurrent.TimeUnit
 import javax.inject.Inject
+import kotlin.math.abs
 
-class EditFragment : Fragment(), MarkdownEditView {
+class EditFragment : Fragment(), MarkdownEditView, ViewPagerPage {
     @Inject
     lateinit var presenter: MarkdownPresenter
     private var markdownEditor: EditText? = null
     private var markdownEditorScroller: ScrollView? = null
 
-    private var lastScrollEvent = -1
-
     @SuppressLint("ClickableViewAccessibility")
     override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                               savedInstanceState: Bundle?): View? {
@@ -68,19 +68,26 @@ class EditFragment : Fragment(), MarkdownEditView {
         super.onViewCreated(view, savedInstanceState)
         presenter.setEditView(this@EditFragment)
 
-        markdownEditorScroller!!.setOnTouchListener { v, event ->
+        var touchDown = 0L
-            // The focus should only be set if this was a click, and not a scroll
+        var oldX = 0f
-            if (lastScrollEvent == MotionEvent.ACTION_DOWN && event.action == MotionEvent.ACTION_UP) {
+        var oldY = 0f
-                if (activity == null) {
+        markdownEditorScroller!!.setOnTouchListener { _, event ->
-                    return@setOnTouchListener false
+            // The ScrollView's onClickListener doesn't seem to be called, so I've had to
+            // implement a sort of custom click listener that checks that the tap was both quick
+            // and didn't drag.
+            when (event?.action) {
+                MotionEvent.ACTION_DOWN -> {
+                    touchDown = System.currentTimeMillis()
+                    oldX = event.rawX
+                    oldY = event.rawY
+                }
+                MotionEvent.ACTION_UP -> {
+                    if (System.currentTimeMillis() - touchDown < 150
+                            && abs(event.rawX - oldX) < 25
+                            && abs(event.rawY - oldY) < 25)
+                        markdownEditor?.showKeyboard()
                 }
-                val imm = activity
-                        ?.getSystemService(Context.INPUT_METHOD_SERVICE) as? InputMethodManager
-                        ?: return@setOnTouchListener false
-                imm.showSoftInput(markdownEditor, InputMethodManager.SHOW_IMPLICIT)
-                markdownEditor!!.requestFocus()
             }
-            lastScrollEvent = event.action
             false
         }
     }
@@ -94,6 +101,15 @@ class EditFragment : Fragment(), MarkdownEditView {
     override fun onPause() {
         super.onPause()
         presenter.setEditView(null)
+        markdownEditor?.hideKeyboard()
+    }
+
+    override fun onSelected() {
+        markdownEditor?.showKeyboard()
+    }
+
+    override fun onDeselected() {
+        markdownEditor?.hideKeyboard()
     }
 
     override fun getMarkdown(): String {

app/src/main/java/com/wbrawner/simplemarkdown/view/fragment/PreviewFragment.kt

@@ -29,18 +29,13 @@ class PreviewFragment : Fragment(), MarkdownPreviewView {
             inflater: LayoutInflater,
             container: ViewGroup?,
             savedInstanceState: Bundle?
-    ): View? {
+    ): View? = inflater.inflate(R.layout.fragment_preview, container, false)
-        sharedPreferences = PreferenceManager.getDefaultSharedPreferences(container!!.context)
+
-        // Inflate the layout for this fragment
+    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
-        val view = inflater.inflate(R.layout.fragment_preview, container, false)
+        sharedPreferences = PreferenceManager.getDefaultSharedPreferences(view.context)
         markdownPreview = view.findViewById(R.id.markdown_view)
-        val activity = activity
+        (activity?.application as? MarkdownApplication)?.component?.inject(this)
-        if (activity != null) {
+        WebView.setWebContentsDebuggingEnabled(BuildConfig.DEBUG)
-            (activity.application as MarkdownApplication).component.inject(this)
-        }
-        if (BuildConfig.DEBUG)
-            WebView.setWebContentsDebuggingEnabled(true)
-        return view
     }
 
     override fun updatePreview(html: String) {