[Android] TextWatcherを使った複数Viewの表示制御

AppTextWatcher.java

package xxx; // TODO change your package name.

import android.text.Editable;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.view.View;

import androidx.annotation.NonNull;

import java.util.Arrays;

public final class AppTextWatcher implements TextWatcher {
    @NonNull
    private final Type mType;
    @NonNull
    private final View[] mViews;

    public AppTextWatcher(
            final @NonNull View... views
    ) {
        this(Type.ENABLED, views);
    }

    public AppTextWatcher(
            final @NonNull Type type,
            final @NonNull View... views) {
        this.mType = type;
        this.mViews = views;
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {

    }

    @Override
    public void afterTextChanged(Editable s) {
        final boolean flag = !TextUtils.isEmpty(s);
        Arrays.stream(mViews).forEach(view -> {
            switch (mType) {
                case ENABLED:
                    view.setEnabled(flag);
                    break;
                case VISIBILITY_INVISIBLE:
                    view.setVisibility(flag ? View.VISIBLE : View.INVISIBLE);
                    break;
                case VISIBILITY_GONE:
                    view.setVisibility(flag ? View.VISIBLE : View.GONE);
                    break;
                case CLICKABLE:
                    view.setClickable(flag);
                    break;
            }
        });
    }

    public enum Type {
        ENABLED, VISIBILITY_INVISIBLE, VISIBILITY_GONE, CLICKABLE
    }
}

Usage 1: default

        final EditText editText = findViewById(R.id.editTextText);
        final Button button = findViewById(R.id.button);
        final Switch switch1 = findViewById(R.id.switch1);
        final CheckBox checkBox = findViewById(R.id.checkBox);
        editText.addTextChangedListener(new AppTextWatcher(button, switch1, checkBox));

API 30

device-2023-07-22-005751.webm

Usage 2: specific Type

        final EditText editText = findViewById(R.id.editTextText);
        final Button button = findViewById(R.id.button);
        final Switch switch1 = findViewById(R.id.switch1);
        final CheckBox checkBox = findViewById(R.id.checkBox);
        editText.addTextChangedListener(
                new AppTextWatcher(
                        AppTextWatcher.Type.VISIBILITY_GONE,
                        button, switch1, checkBox
                )
        );

API 30

device-2023-07-22-010153.webm