TextFieldFocusModifier.android.kt
/*
* Copyright 2022 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.compose.foundation.text
import android.view.InputDevice.KEYBOARD_TYPE_ALPHABETIC
import android.view.KeyEvent.KEYCODE_DPAD_CENTER
import android.view.KeyEvent.KEYCODE_DPAD_DOWN
import android.view.KeyEvent.KEYCODE_DPAD_LEFT
import android.view.KeyEvent.KEYCODE_DPAD_RIGHT
import android.view.KeyEvent.KEYCODE_DPAD_UP
import androidx.compose.ui.Modifier
import androidx.compose.ui.focus.FocusDirection.Companion.Down
import androidx.compose.ui.focus.FocusDirection.Companion.Left
import androidx.compose.ui.focus.FocusDirection.Companion.Right
import androidx.compose.ui.focus.FocusDirection.Companion.Up
import androidx.compose.ui.focus.FocusManager
import androidx.compose.ui.input.key.KeyEventType.Companion.KeyDown
import androidx.compose.ui.input.key.key
import androidx.compose.ui.input.key.nativeKeyCode
import androidx.compose.ui.input.key.onPreviewKeyEvent
import androidx.compose.ui.input.key.type
/**
* TextField consumes the D-pad keys, due to which we can't move focus once a TextField is focused.
* To prevent this, this modifier can be used to intercept D-pad key events before they are sent to
* the TextField. It intercepts and handles the directional (Up, Down, Left, Right & Center) D-pad
* key presses, to move the focus between TextField and other focusable items on the screen.
*/
internal actual fun Modifier.interceptDPadAndMoveFocus(
state: TextFieldState,
focusManager: FocusManager
): Modifier {
return this
.onPreviewKeyEvent { keyEvent ->
// If direction keys from virtual alphabetic keyboard are used, propagate the input
val device = keyEvent.nativeKeyEvent.device ?: return@onPreviewKeyEvent false
if (device.keyboardType == KEYBOARD_TYPE_ALPHABETIC && device.isVirtual) {
return@onPreviewKeyEvent false
}
// Handle only the key press events, ignore key release events
if (keyEvent.type != KeyDown) return@onPreviewKeyEvent false
when (keyEvent.key.nativeKeyCode) {
KEYCODE_DPAD_UP -> focusManager.moveFocus(Up)
KEYCODE_DPAD_DOWN -> focusManager.moveFocus(Down)
KEYCODE_DPAD_LEFT -> focusManager.moveFocus(Left)
KEYCODE_DPAD_RIGHT -> focusManager.moveFocus(Right)
KEYCODE_DPAD_CENTER -> {
// Enable keyboard on center key press
state.inputSession?.showSoftwareKeyboard()
true
}
else -> false
}
}
}