Notes-master/NoteEditText.java

/*
 * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
 *
 * 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 net.micode.notes.ui;

import android.content.Context;
import android.graphics.Rect;
import android.text.Layout;
import android.text.Selection;
import android.text.Spanned;
import android.text.TextUtils;
import android.text.style.URLSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.view.ContextMenu;
import android.view.KeyEvent;
import android.view.MenuItem;
import android.view.MenuItem.OnMenuItemClickListener;
import android.view.MotionEvent;
import android.widget.EditText;

import net.micode.notes.R;

import java.util.HashMap;
import java.util.Map;

public class NoteEditText extends EditText {
    private static final String TAG = "NoteEditText";
    private int mIndex;
    private int mSelectionStartBeforeDelete;

    private static final String SCHEME_TEL = "tel:" ;
    private static final String SCHEME_HTTP = "http:" ;
    private static final String SCHEME_EMAIL = "mailto:" ;

    private static final Map<String, Integer> sSchemaActionResMap = new HashMap<String, Integer>();
    static {
        sSchemaActionResMap.put(SCHEME_TEL, R.string.note_link_tel);
        sSchemaActionResMap.put(SCHEME_HTTP, R.string.note_link_web);
        sSchemaActionResMap.put(SCHEME_EMAIL, R.string.note_link_email);
    }

    /**
     * Call by the {@link NoteEditActivity} to delete or add edit text
     */
    public interface OnTextViewChangeListener {
        /**
         * Delete current edit text when {@link KeyEvent#KEYCODE_DEL} happens
         * and the text is null
         */
        void onEditTextDelete(int index, String text);

        /**
         * Add edit text after current edit text when {@link KeyEvent#KEYCODE_ENTER}
         * happen
         */
        void onEditTextEnter(int index, String text);

        /**
         * Hide or show item option when text change
         */
        void onTextChange(int index, boolean hasText);
    }

  /*
 * Copyright (c) 2010-2011, The MiCode Open Source Community (www.micode.net)
 *
 * 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 net.micode.notes.ui;  // 定义类所在的包路径

// 引入相关的 Android 类
import android.content.Context;
import android.graphics.Rect;
import android.text.Layout;
import android.text.Selection;
import android.text.Spanned;
import android.text.TextUtils;
import android.text.style.URLSpan;
import android.util.AttributeSet;
import android.util.Log;
import android.view.ContextMenu;
import android.view.KeyEvent;
import android.view.MenuItem;
import android.view.MenuItem.OnMenuItemClickListener;
import android.view.MotionEvent;
import android.widget.EditText;

import net.micode.notes.R;  // 引入资源文件中的R类

import java.util.HashMap;
import java.util.Map;

public class NoteEditText extends EditText {
    private static final String TAG = "NoteEditText";  // 定义日志标签，用于调试输出
    private int mIndex;  // 用于表示当前编辑文本的索引
    private int mSelectionStartBeforeDelete;  // 用于记录删除前的文本选择开始位置

    // 定义常见的URI Schemes
    private static final String SCHEME_TEL = "tel:" ;
    private static final String SCHEME_HTTP = "http:" ;
    private static final String SCHEME_EMAIL = "mailto:" ;

    // 定义一个映射关系，存储不同URI Scheme对应的资源ID
    private static final Map<String, Integer> sSchemaActionResMap = new HashMap<String, Integer>();
    static {
        sSchemaActionResMap.put(SCHEME_TEL, R.string.note_link_tel);  // 电话链接对应的资源ID
        sSchemaActionResMap.put(SCHEME_HTTP, R.string.note_link_web);  // 网站链接对应的资源ID
        sSchemaActionResMap.put(SCHEME_EMAIL, R.string.note_link_email);  // 邮件链接对应的资源ID
    }

    /**
     * 在 {@link NoteEditActivity} 中调用，用于删除或添加编辑文本
     */
    public interface OnTextViewChangeListener {
        /**
         * 当发生删除事件（例如按下删除键）且文本为空时，删除当前编辑文本
         */
        void onEditTextDelete(int index, String text);

        /**
         * 当发生回车事件（例如按下回车键）时，添加编辑文本
         */
        void onEditTextEnter(int index, String text);

        /**
         * 当文本发生变化时，隐藏或显示项的选项
         */
        void onTextChange(int index, boolean hasText);
    }
}
// 定义一个文本视图变化监听器的接口
private OnTextViewChangeListener mOnTextViewChangeListener;

// NoteEditText的构造函数，当从AttributeSet创建时调用
public NoteEditText(Context context) {
    super(context, null);
    mIndex = 0;
}

// 设置当前文本编辑框的索引
public void setIndex(int index) {
    mIndex = index;
}

// 设置文本视图变化监听器
public void setOnTextViewChangeListener(OnTextViewChangeListener listener) {
    mOnTextViewChangeListener = listener;
}

// NoteEditText的构造函数，当从AttributeSet和 defStyle创建时调用
public NoteEditText(Context context, AttributeSet attrs) {
    super(context, attrs, android.R.attr.editTextStyle);
}

// NoteEditText的构造函数，当从AttributeSet、defStyle和 defStyle创建时调用
public NoteEditText(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    // TODO Auto-generated constructor stub
}

// 处理触摸事件，用于实现自定义的文本选择行为
@Override
public boolean onTouchEvent(MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            int x = (int) event.getX();
            int y = (int) event.getY();
            x -= getTotalPaddingLeft();
            y -= getTotalPaddingTop();
            x += getScrollX();
            y += getScrollY();

            Layout layout = getLayout();
            int line = layout.getLineForVertical(y);
            int off = layout.getOffsetForHorizontal(line, x);
            Selection.setSelection(getText(), off);
            break;
    }

    return super.onTouchEvent(event);
}

// 处理按键事件，例如Enter和Delete键
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    switch (keyCode) {
        case KeyEvent.KEYCODE_ENTER:
            if (mOnTextViewChangeListener != null) {
                return false;
            }
            break;
        case KeyEvent.KEYCODE_DEL:
            mSelectionStartBeforeDelete = getSelectionStart();
            break;
        default:
            break;
    }
    return super.onKeyDown(keyCode, event);
}

// 处理按键释放事件，例如Enter和Delete键
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
    switch(keyCode) {
        case KeyEvent.KEYCODE_DEL:
            if (mOnTextViewChangeListener != null) {
                if (0 == mSelectionStartBeforeDelete && mIndex != 0) {
                    mOnTextViewChangeListener.onEditTextDelete(mIndex, getText().toString());
                    return true;
                }
            } else {
                Log.d(TAG, "OnTextViewChangeListener was not seted");
            }
            break;
        case KeyEvent.KEYCODE_ENTER:
            if (mOnTextViewChangeListener != null) {
                int selectionStart = getSelectionStart();
                String text = getText().subSequence(selectionStart, length()).toString();
                setText(getText().subSequence(0, selectionStart));
                mOnTextViewChangeListener.onEditTextEnter(mIndex + 1, text);
            } else {
                Log.d(TAG, "OnTextViewChangeListener was not seted");
            }
            break;
        default:
            break;
    }
    return super.onKeyUp(keyCode, event);
}

// 处理焦点变化事件，用于在文本编辑框失去焦点时通知监听器
@Override
protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
    if (mOnTextViewChangeListener != null) {
        if (!focused && TextUtils.isEmpty(getText())) {
            mOnTextViewChangeListener.onTextChange(mIndex, false);
        } else {
            mOnTextViewChangeListener.onTextChange(mIndex, true);
        }
    }
    super.onFocusChanged(focused, direction, previouslyFocusedRect);
}

// 创建上下文菜单，用于实现长按文本时弹出的菜单
@Override
protected void onCreateContextMenu(ContextMenu menu) {
    if (getText() instanceof Spanned) {
        int selStart = getSelectionStart();
        int selEnd = getSelectionEnd();

        int min = Math.min(selStart, selEnd);
        int max = Math.max(selStart, selEnd);

        final URLSpan[] urls = ((Spanned) getText()).getSpans(min, max, URLSpan.class);
        if (urls.length == 1) {
            int defaultResId = 0;
            for(String schema: sSchemaActionResMap.keySet()) {
                if(urls[0].getURL().indexOf(schema) >= 0) {
                    defaultResId = sSchemaActionResMap.get(schema);
                    break;
                }
            }

            if (defaultResId == 0) {
                defaultResId = R.string.note_link_other;
            }

            menu.add(0, 0, 0, defaultResId).setOnMenuItemClickListener(
                    new OnMenuItemClickListener() {
                        public boolean onMenuItemClick(MenuItem item) {
                            // goto a new intent
                            urls[0].onClick(NoteEditText.this);
                            return true;
                        }
                    });
        }
    }
    super.onCreateContextMenu(menu);
}