Implement EditTextPreference

Author: Maxr1998

library/src/main/java/de/Maxr1998/modernpreferences/helpers/PreferencesDsl.kt

@@ -84,6 +84,10 @@ inline fun PreferenceScreen.Appendable.multiChoice(key: String, items: List<Sele
     return MultiChoiceDialogPreference(key, items).apply(block).also(::addPreferenceItem)
 }
 
+inline fun PreferenceScreen.Appendable.editText(key: String, block: EditTextPreference.() -> Unit): EditTextPreference {
+    return EditTextPreference(key).apply(block).also(::addPreferenceItem)
+}
+
 inline fun <reified T : Preference> PreferenceScreen.Appendable.custom(key: String, block: T.() -> Unit): T {
     return T::class.java.getConstructor(String::class.java).newInstance(key).apply(block).also(::addPreferenceItem)
 }

library/src/main/java/de/Maxr1998/modernpreferences/preferences/EditTextPreference.kt

@@ -0,0 +1,97 @@
+package de.Maxr1998.modernpreferences.preferences
+
+import android.app.Dialog
+import android.content.Context
+import android.text.InputType
+import android.view.ViewGroup
+import android.view.ViewGroup.LayoutParams.MATCH_PARENT
+import android.view.ViewGroup.LayoutParams.WRAP_CONTENT
+import android.widget.FrameLayout
+import androidx.annotation.StringRes
+import androidx.appcompat.app.AlertDialog
+import androidx.appcompat.widget.AppCompatEditText
+
+class EditTextPreference(key: String) : DialogPreference(key) {
+
+    var currentInput: CharSequence? = null
+        private set
+
+    /**
+     * The [InputType] applied to the contained [EditText][AppCompatEditText]
+     */
+    var textInputType: Int = InputType.TYPE_NULL
+
+    @StringRes
+    var textInputHintRes: Int = -1
+    var textInputHint: CharSequence? = null
+
+    var textChangeListener: OnTextChangeListener? = null
+
+    /**
+     * Allows to override the summary, providing the current input value when called.
+     *
+     * Summary falls back to [summary] or [summaryRes] when null is returned.
+     */
+    var summaryProvider: (CharSequence?) -> CharSequence? = { null }
+
+    override fun onAttach() {
+        super.onAttach()
+        if (currentInput == null)
+            currentInput = getString()
+    }
+
+    override fun createDialog(context: Context): Dialog = AlertDialog.Builder(context).apply {
+        if (titleRes != -1) setTitle(titleRes) else setTitle(title)
+        val editText = AppCompatEditText(context).apply {
+            if (textInputType != InputType.TYPE_NULL) {
+                inputType = textInputType
+            }
+            when {
+                textInputHintRes != -1 -> setHint(textInputHintRes)
+                textInputHint != null -> hint = textInputHint
+            }
+            setText(currentInput)
+        }
+        setView(FrameLayout(context).apply {
+            val layoutParams = ViewGroup.MarginLayoutParams(MATCH_PARENT, WRAP_CONTENT).apply {
+                val tenDp = (10 * context.resources.displayMetrics.density).toInt()
+                marginStart = 2 * tenDp
+                marginEnd = 2 * tenDp
+                topMargin = tenDp
+            }
+            addView(editText, layoutParams)
+        })
+        setCancelable(false)
+        setPositiveButton(android.R.string.ok) { _, _ ->
+            editText.text?.let(::persist)
+            requestRebind()
+        }
+        setNegativeButton(android.R.string.cancel) { _, _ ->
+            editText.setText(currentInput)
+        }
+    }.create()
+
+    private fun persist(input: CharSequence) {
+        if (textChangeListener?.onTextChange(this, input) != false) {
+            currentInput = input
+            commitString(input.toString())
+        }
+    }
+
+    override fun resolveSummary(context: Context): CharSequence? {
+        return summaryProvider(currentInput) ?: super.resolveSummary(context)
+    }
+
+    fun interface OnTextChangeListener {
+        /**
+         * Notified when the value of the connected [EditTextPreference] changes,
+         * meaning after the user closes the dialog by pressing "ok".
+         * This is called before the change gets persisted and can be prevented by returning false.
+         *
+         * @param text the new value
+         *
+         * @return true to commit the new value to [SharedPreferences][android.content.SharedPreferences]
+         */
+        fun onTextChange(preference: EditTextPreference, text: CharSequence): Boolean
+    }
+}

testapp/src/main/java/de/Maxr1998/modernpreferences/example/Common.kt

@@ -130,6 +130,10 @@ object Common {
             multiChoice("multi-choice-dialog", selectableItems) {
                 title = "Multi choice selection dialog"
             }
+            editText("edit-text") {
+                title = "Text input"
+                textInputHint = "Enter whatever you want!"
+            }
             expandText("expand-text") {
                 title = "Expandable text"
                 text = "This is an example implementation of ModernAndroidPreferences, check out " +