shell/platform/android/io/flutter/plugin/editing/TextInputPlugin.java - mirrors/engine - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 package io.flutter.plugin.editing;

 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.os.Build;
 import android.provider.Settings;
 import android.text.Editable;
 import android.text.InputType;
 import android.text.Selection;
 import android.view.View;
 import android.view.inputmethod.BaseInputConnection;
 import android.view.inputmethod.EditorInfo;
 import android.view.inputmethod.InputConnection;
 import android.view.inputmethod.InputMethodManager;
 import android.view.inputmethod.InputMethodSubtype;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 import io.flutter.embedding.engine.dart.DartExecutor;
 import io.flutter.embedding.engine.systemchannels.TextInputChannel;
 import io.flutter.plugin.platform.PlatformViewsController;

 /** Android implementation of the text input plugin. */
 public class TextInputPlugin {
   @NonNull private final View mView;
   @NonNull private final InputMethodManager mImm;
   @NonNull private final TextInputChannel textInputChannel;
   @NonNull private InputTarget inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
   @Nullable private TextInputChannel.Configuration configuration;
   @Nullable private Editable mEditable;
   private boolean mRestartInputPending;
   @Nullable private InputConnection lastInputConnection;
   @NonNull private PlatformViewsController platformViewsController;
   private final boolean restartAlwaysRequired;

   // When true following calls to createInputConnection will return the cached lastInputConnection
   // if the input
   // target is a platform view. See the comments on lockPlatformViewInputConnection for more
   // details.
   private boolean isInputConnectionLocked;

   public TextInputPlugin(
       View view,
       @NonNull DartExecutor dartExecutor,
       @NonNull PlatformViewsController platformViewsController) {
     mView = view;
     mImm = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);

     textInputChannel = new TextInputChannel(dartExecutor);
     textInputChannel.setTextInputMethodHandler(
         new TextInputChannel.TextInputMethodHandler() {
           @Override
           public void show() {
             showTextInput(mView);
           }

           @Override
           public void hide() {
             hideTextInput(mView);
           }

           @Override
           public void setClient(
               int textInputClientId, TextInputChannel.Configuration configuration) {
             setTextInputClient(textInputClientId, configuration);
           }

           @Override
           public void setPlatformViewClient(int platformViewId) {
             setPlatformViewTextInputClient(platformViewId);
           }

           @Override
           public void setEditingState(TextInputChannel.TextEditState editingState) {
             setTextInputEditingState(mView, editingState);
           }

           @Override
           public void clearClient() {
             clearTextInputClient();
           }
         });

     textInputChannel.requestExistingInputState();

     this.platformViewsController = platformViewsController;
     this.platformViewsController.attachTextInputPlugin(this);
     restartAlwaysRequired = isRestartAlwaysRequired();
   }

   @NonNull
   public InputMethodManager getInputMethodManager() {
     return mImm;
   }

   @VisibleForTesting
   Editable getEditable() {
     return mEditable;
   }

   /**
    * * Use the current platform view input connection until unlockPlatformViewInputConnection is
    * called.
    *
    * <p>The current input connection instance is cached and any following call to @{link
    * createInputConnection} returns the cached connection until unlockPlatformViewInputConnection is
    * called.
    *
    * <p>This is a no-op if the current input target isn't a platform view.
    *
    * <p>This is used to preserve an input connection when moving a platform view from one virtual
    * display to another.
    */
   public void lockPlatformViewInputConnection() {
     if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
       isInputConnectionLocked = true;
     }
   }

   /**
    * Unlocks the input connection.
    *
    * <p>See also: @{link lockPlatformViewInputConnection}.
    */
   public void unlockPlatformViewInputConnection() {
     isInputConnectionLocked = false;
   }

   /**
    * Detaches the text input plugin from the platform views controller.
    *
    * <p>The TextInputPlugin instance should not be used after calling this.
    */
   public void destroy() {
     platformViewsController.detachTextInputPlugin();
   }

   private static int inputTypeFromTextInputType(
       TextInputChannel.InputType type,
       boolean obscureText,
       boolean autocorrect,
       boolean enableSuggestions,
       TextInputChannel.TextCapitalization textCapitalization) {
     if (type.type == TextInputChannel.TextInputType.DATETIME) {
       return InputType.TYPE_CLASS_DATETIME;
     } else if (type.type == TextInputChannel.TextInputType.NUMBER) {
       int textType = InputType.TYPE_CLASS_NUMBER;
       if (type.isSigned) {
         textType |= InputType.TYPE_NUMBER_FLAG_SIGNED;
       }
       if (type.isDecimal) {
         textType |= InputType.TYPE_NUMBER_FLAG_DECIMAL;
       }
       return textType;
     } else if (type.type == TextInputChannel.TextInputType.PHONE) {
       return InputType.TYPE_CLASS_PHONE;
     }

     int textType = InputType.TYPE_CLASS_TEXT;
     if (type.type == TextInputChannel.TextInputType.MULTILINE) {
       textType |= InputType.TYPE_TEXT_FLAG_MULTI_LINE;
     } else if (type.type == TextInputChannel.TextInputType.EMAIL_ADDRESS) {
       textType |= InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS;
     } else if (type.type == TextInputChannel.TextInputType.URL) {
       textType |= InputType.TYPE_TEXT_VARIATION_URI;
     } else if (type.type == TextInputChannel.TextInputType.VISIBLE_PASSWORD) {
       textType |= InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD;
     }

     if (obscureText) {
       // Note: both required. Some devices ignore TYPE_TEXT_FLAG_NO_SUGGESTIONS.
       textType |= InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
       textType |= InputType.TYPE_TEXT_VARIATION_PASSWORD;
     } else {
       if (autocorrect) textType |= InputType.TYPE_TEXT_FLAG_AUTO_CORRECT;
       if (!enableSuggestions) textType |= InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
     }

     if (textCapitalization == TextInputChannel.TextCapitalization.CHARACTERS) {
       textType |= InputType.TYPE_TEXT_FLAG_CAP_CHARACTERS;
     } else if (textCapitalization == TextInputChannel.TextCapitalization.WORDS) {
       textType |= InputType.TYPE_TEXT_FLAG_CAP_WORDS;
     } else if (textCapitalization == TextInputChannel.TextCapitalization.SENTENCES) {
       textType |= InputType.TYPE_TEXT_FLAG_CAP_SENTENCES;
     }

     return textType;
   }

   public InputConnection createInputConnection(View view, EditorInfo outAttrs) {
     if (inputTarget.type == InputTarget.Type.NO_TARGET) {
       lastInputConnection = null;
       return null;
     }

     if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
       if (isInputConnectionLocked) {
         return lastInputConnection;
       }
       lastInputConnection =
           platformViewsController
               .getPlatformViewById(inputTarget.id)
               .onCreateInputConnection(outAttrs);
       return lastInputConnection;
     }

     outAttrs.inputType =
         inputTypeFromTextInputType(
             configuration.inputType,
             configuration.obscureText,
             configuration.autocorrect,
             configuration.enableSuggestions,
             configuration.textCapitalization);
     outAttrs.imeOptions = EditorInfo.IME_FLAG_NO_FULLSCREEN;
     int enterAction;
     if (configuration.inputAction == null) {
       // If an explicit input action isn't set, then default to none for multi-line fields
       // and done for single line fields.
       enterAction =
           (InputType.TYPE_TEXT_FLAG_MULTI_LINE & outAttrs.inputType) != 0
               ? EditorInfo.IME_ACTION_NONE
               : EditorInfo.IME_ACTION_DONE;
     } else {
       enterAction = configuration.inputAction;
     }
     if (configuration.actionLabel != null) {
       outAttrs.actionLabel = configuration.actionLabel;
       outAttrs.actionId = enterAction;
     }
     outAttrs.imeOptions |= enterAction;

     InputConnectionAdaptor connection =
         new InputConnectionAdaptor(view, inputTarget.id, textInputChannel, mEditable, outAttrs);
     outAttrs.initialSelStart = Selection.getSelectionStart(mEditable);
     outAttrs.initialSelEnd = Selection.getSelectionEnd(mEditable);

     lastInputConnection = connection;
     return lastInputConnection;
   }

   @Nullable
   public InputConnection getLastInputConnection() {
     return lastInputConnection;
   }

   /**
    * Clears a platform view text input client if it is the current input target.
    *
    * <p>This is called when a platform view is disposed to make sure we're not hanging to a stale
    * input connection.
    */
   public void clearPlatformViewClient(int platformViewId) {
     if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW && inputTarget.id == platformViewId) {
       inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
       hideTextInput(mView);
       mImm.restartInput(mView);
       mRestartInputPending = false;
     }
   }

   private void showTextInput(View view) {
     view.requestFocus();
     mImm.showSoftInput(view, 0);
   }

   private void hideTextInput(View view) {
     // Note: a race condition may lead to us hiding the keyboard here just after a platform view has
     // shown it.
     // This can only potentially happen when switching focus from a Flutter text field to a platform
     // view's text
     // field(by text field here I mean anything that keeps the keyboard open).
     // See: https://github.com/flutter/flutter/issues/34169
     mImm.hideSoftInputFromWindow(view.getApplicationWindowToken(), 0);
   }

   @VisibleForTesting
   void setTextInputClient(int client, TextInputChannel.Configuration configuration) {
     inputTarget = new InputTarget(InputTarget.Type.FRAMEWORK_CLIENT, client);
     this.configuration = configuration;
     mEditable = Editable.Factory.getInstance().newEditable("");

     // setTextInputClient will be followed by a call to setTextInputEditingState.
     // Do a restartInput at that time.
     mRestartInputPending = true;
     unlockPlatformViewInputConnection();
   }

   private void setPlatformViewTextInputClient(int platformViewId) {
     // We need to make sure that the Flutter view is focused so that no imm operations get short
     // circuited.
     // Not asking for focus here specifically manifested in a but on API 28 devices where the
     // platform view's
     // request to show a keyboard was ignored.
     mView.requestFocus();
     inputTarget = new InputTarget(InputTarget.Type.PLATFORM_VIEW, platformViewId);
     mImm.restartInput(mView);
     mRestartInputPending = false;
   }

   private void applyStateToSelection(TextInputChannel.TextEditState state) {
     int selStart = state.selectionStart;
     int selEnd = state.selectionEnd;
     if (selStart >= 0
         && selStart <= mEditable.length()
         && selEnd >= 0
         && selEnd <= mEditable.length()) {
       Selection.setSelection(mEditable, selStart, selEnd);
     } else {
       Selection.removeSelection(mEditable);
     }
   }

   @VisibleForTesting
   void setTextInputEditingState(View view, TextInputChannel.TextEditState state) {
     // Always replace the contents of mEditable if the text differs
     if (!state.text.equals(mEditable.toString())) {
       mEditable.replace(0, mEditable.length(), state.text);
     }
     // Always apply state to selection which handles updating the selection if needed.
     applyStateToSelection(state);
     InputConnection connection = getLastInputConnection();
     if (connection != null && connection instanceof InputConnectionAdaptor) {
       ((InputConnectionAdaptor) connection).markDirty();
     }
     // Use updateSelection to update imm on selection if it is not neccessary to restart.
     if (!restartAlwaysRequired && !mRestartInputPending) {
       mImm.updateSelection(
           mView,
           Math.max(Selection.getSelectionStart(mEditable), 0),
           Math.max(Selection.getSelectionEnd(mEditable), 0),
           BaseInputConnection.getComposingSpanStart(mEditable),
           BaseInputConnection.getComposingSpanEnd(mEditable));
       // Restart if there is a pending restart or the device requires a force restart
       // (see isRestartAlwaysRequired). Restarting will also update the selection.
     } else {
       mImm.restartInput(view);
       mRestartInputPending = false;
     }
   }

   // Samsung's Korean keyboard has a bug where it always attempts to combine characters based on
   // its internal state, ignoring if and when the cursor is moved programmatically. The same bug
   // also causes non-korean keyboards to occasionally duplicate text when tapping in the middle
   // of existing text to edit it.
   //
   // Fully restarting the IMM works around this because it flushes the keyboard's internal state
   // and stops it from trying to incorrectly combine characters. However this also has some
   // negative performance implications, so we don't want to apply this workaround in every case.
   @SuppressLint("NewApi") // New API guard is inline, the linter can't see it.
   @SuppressWarnings("deprecation")
   private boolean isRestartAlwaysRequired() {
     InputMethodSubtype subtype = mImm.getCurrentInputMethodSubtype();
     // Impacted devices all shipped with Android Lollipop or newer.
     if (subtype == null
         || Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP
         || !Build.MANUFACTURER.equals("samsung")) {
       return false;
     }
     String keyboardName =
         Settings.Secure.getString(
             mView.getContext().getContentResolver(), Settings.Secure.DEFAULT_INPUT_METHOD);
     // The Samsung keyboard is called "com.sec.android.inputmethod/.SamsungKeypad" but look
     // for "Samsung" just in case Samsung changes the name of the keyboard.
     return keyboardName.contains("Samsung");
   }

   private void clearTextInputClient() {
     if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
       // Focus changes in the framework tree have no guarantees on the order focus nodes are
       // notified. A node
       // that lost focus may be notified before or after a node that gained focus.
       // When moving the focus from a Flutter text field to an AndroidView, it is possible that the
       // Flutter text
       // field's focus node will be notified that it lost focus after the AndroidView was notified
       // that it gained
       // focus. When this happens the text field will send a clearTextInput command which we ignore.
       // By doing this we prevent the framework from clearing a platform view input client(the only
       // way to do so
       // is to set a new framework text client). I don't see an obvious use case for "clearing" a
       // platform views
       // text input client, and it may be error prone as we don't know how the platform view manages
       // the input
       // connection and we probably shouldn't interfere.
       // If we ever want to allow the framework to clear a platform view text client we should
       // probably consider
       // changing the focus manager such that focus nodes that lost focus are notified before focus
       // nodes that
       // gained focus as part of the same focus event.
       return;
     }
     inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
     unlockPlatformViewInputConnection();
   }

   private static class InputTarget {
     enum Type {
       NO_TARGET,
       // InputConnection is managed by the TextInputPlugin, and events are forwarded to the Flutter
       // framework.
       FRAMEWORK_CLIENT,
       // InputConnection is managed by an embedded platform view.
       PLATFORM_VIEW
     }

     public InputTarget(@NonNull Type type, int id) {
       this.type = type;
       this.id = id;
     }

     @NonNull Type type;
     // The ID of the input target.
     //
     // For framework clients this is the framework input connection client ID.
     // For platform views this is the platform view's ID.
     int id;
   }
 }
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	package io.flutter.plugin.editing;

	import android.annotation.SuppressLint;
	import android.content.Context;
	import android.os.Build;
	import android.provider.Settings;
	import android.text.Editable;
	import android.text.InputType;
	import android.text.Selection;
	import android.view.View;
	import android.view.inputmethod.BaseInputConnection;
	import android.view.inputmethod.EditorInfo;
	import android.view.inputmethod.InputConnection;
	import android.view.inputmethod.InputMethodManager;
	import android.view.inputmethod.InputMethodSubtype;
	import androidx.annotation.NonNull;
	import androidx.annotation.Nullable;
	import androidx.annotation.VisibleForTesting;
	import io.flutter.embedding.engine.dart.DartExecutor;
	import io.flutter.embedding.engine.systemchannels.TextInputChannel;
	import io.flutter.plugin.platform.PlatformViewsController;

	/** Android implementation of the text input plugin. */
	public class TextInputPlugin {
	@NonNull private final View mView;
	@NonNull private final InputMethodManager mImm;
	@NonNull private final TextInputChannel textInputChannel;
	@NonNull private InputTarget inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
	@Nullable private TextInputChannel.Configuration configuration;
	@Nullable private Editable mEditable;
	private boolean mRestartInputPending;
	@Nullable private InputConnection lastInputConnection;
	@NonNull private PlatformViewsController platformViewsController;
	private final boolean restartAlwaysRequired;

	// When true following calls to createInputConnection will return the cached lastInputConnection
	// if the input
	// target is a platform view. See the comments on lockPlatformViewInputConnection for more
	// details.
	private boolean isInputConnectionLocked;

	public TextInputPlugin(
	View view,
	@NonNull DartExecutor dartExecutor,
	@NonNull PlatformViewsController platformViewsController) {
	mView = view;
	mImm = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);

	textInputChannel = new TextInputChannel(dartExecutor);
	textInputChannel.setTextInputMethodHandler(
	new TextInputChannel.TextInputMethodHandler() {
	@Override
	public void show() {
	showTextInput(mView);
	}

	@Override
	public void hide() {
	hideTextInput(mView);
	}

	@Override
	public void setClient(
	int textInputClientId, TextInputChannel.Configuration configuration) {
	setTextInputClient(textInputClientId, configuration);
	}

	@Override
	public void setPlatformViewClient(int platformViewId) {
	setPlatformViewTextInputClient(platformViewId);
	}

	@Override
	public void setEditingState(TextInputChannel.TextEditState editingState) {
	setTextInputEditingState(mView, editingState);
	}

	@Override
	public void clearClient() {
	clearTextInputClient();
	}
	});

	textInputChannel.requestExistingInputState();

	this.platformViewsController = platformViewsController;
	this.platformViewsController.attachTextInputPlugin(this);
	restartAlwaysRequired = isRestartAlwaysRequired();
	}

	@NonNull
	public InputMethodManager getInputMethodManager() {
	return mImm;
	}

	@VisibleForTesting
	Editable getEditable() {
	return mEditable;
	}

	/**
	* * Use the current platform view input connection until unlockPlatformViewInputConnection is
	* called.
	*
	* <p>The current input connection instance is cached and any following call to @{link
	* createInputConnection} returns the cached connection until unlockPlatformViewInputConnection is
	* called.
	*
	* <p>This is a no-op if the current input target isn't a platform view.
	*
	* <p>This is used to preserve an input connection when moving a platform view from one virtual
	* display to another.
	*/
	public void lockPlatformViewInputConnection() {
	if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
	isInputConnectionLocked = true;
	}
	}

	/**
	* Unlocks the input connection.
	*
	* <p>See also: @{link lockPlatformViewInputConnection}.
	*/
	public void unlockPlatformViewInputConnection() {
	isInputConnectionLocked = false;
	}

	/**
	* Detaches the text input plugin from the platform views controller.
	*
	* <p>The TextInputPlugin instance should not be used after calling this.
	*/
	public void destroy() {
	platformViewsController.detachTextInputPlugin();
	}

	private static int inputTypeFromTextInputType(
	TextInputChannel.InputType type,
	boolean obscureText,
	boolean autocorrect,
	boolean enableSuggestions,
	TextInputChannel.TextCapitalization textCapitalization) {
	if (type.type == TextInputChannel.TextInputType.DATETIME) {
	return InputType.TYPE_CLASS_DATETIME;
	} else if (type.type == TextInputChannel.TextInputType.NUMBER) {
	int textType = InputType.TYPE_CLASS_NUMBER;
	if (type.isSigned) {
	textType \|= InputType.TYPE_NUMBER_FLAG_SIGNED;
	}
	if (type.isDecimal) {
	textType \|= InputType.TYPE_NUMBER_FLAG_DECIMAL;
	}
	return textType;
	} else if (type.type == TextInputChannel.TextInputType.PHONE) {
	return InputType.TYPE_CLASS_PHONE;
	}

	int textType = InputType.TYPE_CLASS_TEXT;
	if (type.type == TextInputChannel.TextInputType.MULTILINE) {
	textType \|= InputType.TYPE_TEXT_FLAG_MULTI_LINE;
	} else if (type.type == TextInputChannel.TextInputType.EMAIL_ADDRESS) {
	textType \|= InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS;
	} else if (type.type == TextInputChannel.TextInputType.URL) {
	textType \|= InputType.TYPE_TEXT_VARIATION_URI;
	} else if (type.type == TextInputChannel.TextInputType.VISIBLE_PASSWORD) {
	textType \|= InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD;
	}

	if (obscureText) {
	// Note: both required. Some devices ignore TYPE_TEXT_FLAG_NO_SUGGESTIONS.
	textType \|= InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
	textType \|= InputType.TYPE_TEXT_VARIATION_PASSWORD;
	} else {
	if (autocorrect) textType \|= InputType.TYPE_TEXT_FLAG_AUTO_CORRECT;
	if (!enableSuggestions) textType \|= InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
	}

	if (textCapitalization == TextInputChannel.TextCapitalization.CHARACTERS) {
	textType \|= InputType.TYPE_TEXT_FLAG_CAP_CHARACTERS;
	} else if (textCapitalization == TextInputChannel.TextCapitalization.WORDS) {
	textType \|= InputType.TYPE_TEXT_FLAG_CAP_WORDS;
	} else if (textCapitalization == TextInputChannel.TextCapitalization.SENTENCES) {
	textType \|= InputType.TYPE_TEXT_FLAG_CAP_SENTENCES;
	}

	return textType;
	}

	public InputConnection createInputConnection(View view, EditorInfo outAttrs) {
	if (inputTarget.type == InputTarget.Type.NO_TARGET) {
	lastInputConnection = null;
	return null;
	}

	if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
	if (isInputConnectionLocked) {
	return lastInputConnection;
	}
	lastInputConnection =
	platformViewsController
	.getPlatformViewById(inputTarget.id)
	.onCreateInputConnection(outAttrs);
	return lastInputConnection;
	}

	outAttrs.inputType =
	inputTypeFromTextInputType(
	configuration.inputType,
	configuration.obscureText,
	configuration.autocorrect,
	configuration.enableSuggestions,
	configuration.textCapitalization);
	outAttrs.imeOptions = EditorInfo.IME_FLAG_NO_FULLSCREEN;
	int enterAction;
	if (configuration.inputAction == null) {
	// If an explicit input action isn't set, then default to none for multi-line fields
	// and done for single line fields.
	enterAction =
	(InputType.TYPE_TEXT_FLAG_MULTI_LINE & outAttrs.inputType) != 0
	? EditorInfo.IME_ACTION_NONE
	: EditorInfo.IME_ACTION_DONE;
	} else {
	enterAction = configuration.inputAction;
	}
	if (configuration.actionLabel != null) {
	outAttrs.actionLabel = configuration.actionLabel;
	outAttrs.actionId = enterAction;
	}
	outAttrs.imeOptions \|= enterAction;

	InputConnectionAdaptor connection =
	new InputConnectionAdaptor(view, inputTarget.id, textInputChannel, mEditable, outAttrs);
	outAttrs.initialSelStart = Selection.getSelectionStart(mEditable);
	outAttrs.initialSelEnd = Selection.getSelectionEnd(mEditable);

	lastInputConnection = connection;
	return lastInputConnection;
	}

	@Nullable
	public InputConnection getLastInputConnection() {
	return lastInputConnection;
	}

	/**
	* Clears a platform view text input client if it is the current input target.
	*
	* <p>This is called when a platform view is disposed to make sure we're not hanging to a stale
	* input connection.
	*/
	public void clearPlatformViewClient(int platformViewId) {
	if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW && inputTarget.id == platformViewId) {
	inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
	hideTextInput(mView);
	mImm.restartInput(mView);
	mRestartInputPending = false;
	}
	}

	private void showTextInput(View view) {
	view.requestFocus();
	mImm.showSoftInput(view, 0);
	}

	private void hideTextInput(View view) {
	// Note: a race condition may lead to us hiding the keyboard here just after a platform view has
	// shown it.
	// This can only potentially happen when switching focus from a Flutter text field to a platform
	// view's text
	// field(by text field here I mean anything that keeps the keyboard open).
	// See: https://github.com/flutter/flutter/issues/34169
	mImm.hideSoftInputFromWindow(view.getApplicationWindowToken(), 0);
	}

	@VisibleForTesting
	void setTextInputClient(int client, TextInputChannel.Configuration configuration) {
	inputTarget = new InputTarget(InputTarget.Type.FRAMEWORK_CLIENT, client);
	this.configuration = configuration;
	mEditable = Editable.Factory.getInstance().newEditable("");

	// setTextInputClient will be followed by a call to setTextInputEditingState.
	// Do a restartInput at that time.
	mRestartInputPending = true;
	unlockPlatformViewInputConnection();
	}

	private void setPlatformViewTextInputClient(int platformViewId) {
	// We need to make sure that the Flutter view is focused so that no imm operations get short
	// circuited.
	// Not asking for focus here specifically manifested in a but on API 28 devices where the
	// platform view's
	// request to show a keyboard was ignored.
	mView.requestFocus();
	inputTarget = new InputTarget(InputTarget.Type.PLATFORM_VIEW, platformViewId);
	mImm.restartInput(mView);
	mRestartInputPending = false;
	}

	private void applyStateToSelection(TextInputChannel.TextEditState state) {
	int selStart = state.selectionStart;
	int selEnd = state.selectionEnd;
	if (selStart >= 0
	&& selStart <= mEditable.length()
	&& selEnd >= 0
	&& selEnd <= mEditable.length()) {
	Selection.setSelection(mEditable, selStart, selEnd);
	} else {
	Selection.removeSelection(mEditable);
	}
	}

	@VisibleForTesting
	void setTextInputEditingState(View view, TextInputChannel.TextEditState state) {
	// Always replace the contents of mEditable if the text differs
	if (!state.text.equals(mEditable.toString())) {
	mEditable.replace(0, mEditable.length(), state.text);
	}
	// Always apply state to selection which handles updating the selection if needed.
	applyStateToSelection(state);
	InputConnection connection = getLastInputConnection();
	if (connection != null && connection instanceof InputConnectionAdaptor) {
	((InputConnectionAdaptor) connection).markDirty();
	}
	// Use updateSelection to update imm on selection if it is not neccessary to restart.
	if (!restartAlwaysRequired && !mRestartInputPending) {
	mImm.updateSelection(
	mView,
	Math.max(Selection.getSelectionStart(mEditable), 0),
	Math.max(Selection.getSelectionEnd(mEditable), 0),
	BaseInputConnection.getComposingSpanStart(mEditable),
	BaseInputConnection.getComposingSpanEnd(mEditable));
	// Restart if there is a pending restart or the device requires a force restart
	// (see isRestartAlwaysRequired). Restarting will also update the selection.
	} else {
	mImm.restartInput(view);
	mRestartInputPending = false;
	}
	}

	// Samsung's Korean keyboard has a bug where it always attempts to combine characters based on
	// its internal state, ignoring if and when the cursor is moved programmatically. The same bug
	// also causes non-korean keyboards to occasionally duplicate text when tapping in the middle
	// of existing text to edit it.
	//
	// Fully restarting the IMM works around this because it flushes the keyboard's internal state
	// and stops it from trying to incorrectly combine characters. However this also has some
	// negative performance implications, so we don't want to apply this workaround in every case.
	@SuppressLint("NewApi") // New API guard is inline, the linter can't see it.
	@SuppressWarnings("deprecation")
	private boolean isRestartAlwaysRequired() {
	InputMethodSubtype subtype = mImm.getCurrentInputMethodSubtype();
	// Impacted devices all shipped with Android Lollipop or newer.
	if (subtype == null
	\|\| Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP
	\|\| !Build.MANUFACTURER.equals("samsung")) {
	return false;
	}
	String keyboardName =
	Settings.Secure.getString(
	mView.getContext().getContentResolver(), Settings.Secure.DEFAULT_INPUT_METHOD);
	// The Samsung keyboard is called "com.sec.android.inputmethod/.SamsungKeypad" but look
	// for "Samsung" just in case Samsung changes the name of the keyboard.
	return keyboardName.contains("Samsung");
	}

	private void clearTextInputClient() {
	if (inputTarget.type == InputTarget.Type.PLATFORM_VIEW) {
	// Focus changes in the framework tree have no guarantees on the order focus nodes are
	// notified. A node
	// that lost focus may be notified before or after a node that gained focus.
	// When moving the focus from a Flutter text field to an AndroidView, it is possible that the
	// Flutter text
	// field's focus node will be notified that it lost focus after the AndroidView was notified
	// that it gained
	// focus. When this happens the text field will send a clearTextInput command which we ignore.
	// By doing this we prevent the framework from clearing a platform view input client(the only
	// way to do so
	// is to set a new framework text client). I don't see an obvious use case for "clearing" a
	// platform views
	// text input client, and it may be error prone as we don't know how the platform view manages
	// the input
	// connection and we probably shouldn't interfere.
	// If we ever want to allow the framework to clear a platform view text client we should
	// probably consider
	// changing the focus manager such that focus nodes that lost focus are notified before focus
	// nodes that
	// gained focus as part of the same focus event.
	return;
	}
	inputTarget = new InputTarget(InputTarget.Type.NO_TARGET, 0);
	unlockPlatformViewInputConnection();
	}

	private static class InputTarget {
	enum Type {
	NO_TARGET,
	// InputConnection is managed by the TextInputPlugin, and events are forwarded to the Flutter
	// framework.
	FRAMEWORK_CLIENT,
	// InputConnection is managed by an embedded platform view.
	PLATFORM_VIEW
	}

	public InputTarget(@NonNull Type type, int id) {
	this.type = type;
	this.id = id;
	}

	@NonNull Type type;
	// The ID of the input target.
	//
	// For framework clients this is the framework input connection client ID.
	// For platform views this is the platform view's ID.
	int id;
	}
	}