Android自定义键盘（KeyboardView）

1.场景：

项目中有定制的设备需要放在室外，用户使用时使用系统自带的键盘肯能没有那么方便，所以就需要使用到了自定义键盘

（结尾附上完整代码可以直接使用,不想看过程的可以直接跳过）

2.想法：

封装成一个比较通用的，当成一个View一样来使用

**实现自定义键盘思路:**
 1. 在res包下创建xml目录,Keyboard标签来定义键盘布局
 2. 创建IKeyboardView类并继承KeyboardView类,设置键盘布局（数字和字母）
 3. 处理自定义键盘按键的点击事件以及预览，并实现数字和字母键盘(包括大小写)之间的切换
 4. 绑定EditText，并且屏蔽系统键盘（实现点击切换绑定多个EditText）
 5. 使用

3.开始实现：

《一》 在res包下创建xml目录,Keyboard标签来定义键盘布局：

创建keyboard_num.xml文件（数字键盘布局）

<?xml version="1.0" encoding="utf-8"?>
<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
    android:keyWidth="10%p"
    android:keyHeight="7%p"
    android:horizontalGap="0.0px"
    android:verticalGap="0.0px">
    <Row android:verticalGap="1%p">
        <Key
            android:codes="113"
            android:keyLabel="q"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="119"
            android:keyLabel="w"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="101"
            android:keyLabel="e"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="114"
            android:keyLabel="r"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="116"
            android:keyLabel="t"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="121"
            android:keyLabel="y"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="117"
            android:keyLabel="y"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="105"
            android:keyLabel="i"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="111"
            android:keyLabel="o"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="112"
            android:keyLabel="p"
            android:horizontalGap="1.81%p">

        </Key>
    </Row>
    <Row android:verticalGap="1%p">
        <Key
            android:codes="97"
            android:keyLabel="a"
            android:keyWidth="9%p"
            android:horizontalGap="5.5%p">

        </Key>
        <Key
            android:codes="115"
            android:keyLabel="s"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="100"
            android:keyLabel="d"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="102"
            android:keyLabel="f"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="103"
            android:keyLabel="g"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="104"
            android:keyLabel="h"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="106"
            android:keyLabel="j"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="107"
            android:keyLabel="k"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="108"
            android:keyLabel="l"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
    </Row>
    <Row android:verticalGap="1%p">
        <Key
            android:codes="-1"
            android:keyLabel="大写"
            android:keyWidth="17%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="122"
            android:keyLabel="z"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="120"
            android:keyLabel="x"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="99"
            android:keyLabel="c"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="118"
            android:keyLabel="v"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="98"
            android:keyLabel="b"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="110"
            android:keyLabel="n"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="109"
            android:keyLabel="m"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="-5"
            android:isRepeatable="true"
            android:keyWidth="17%p"
            android:horizontalGap="1%p">

        </Key>
    </Row>
    <Row>
        <Key
            android:codes="-2"
            android:keyLabel="123"
            android:keyWidth="20%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="32"
            android:keyLabel="space"
            android:keyWidth="48%p"
            android:horizontalGap="5%p">

        </Key>
        <Key
            android:codes="-4"
            android:keyLabel="完成"
            android:keyWidth="20%p"
            android:horizontalGap="5%p">

        </Key>
    </Row>
</Keyboard>

创建keyboard_letter.xml文件（字母键盘布局）

<?xml version="1.0" encoding="utf-8"?>
<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
    android:keyWidth="10%p"
    android:keyHeight="7%p"
    android:horizontalGap="0.0px"
    android:verticalGap="0.0px">
    <Row android:verticalGap="1%p">
        <Key
            android:codes="113"
            android:keyLabel="q"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="119"
            android:keyLabel="w"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="101"
            android:keyLabel="e"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="114"
            android:keyLabel="r"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="116"
            android:keyLabel="t"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="121"
            android:keyLabel="y"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="117"
            android:keyLabel="y"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="105"
            android:keyLabel="i"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="111"
            android:keyLabel="o"
            android:horizontalGap="1.81%p">

        </Key>
        <Key
            android:codes="112"
            android:keyLabel="p"
            android:horizontalGap="1.81%p">

        </Key>
    </Row>
    <Row android:verticalGap="1%p">
        <Key
            android:codes="97"
            android:keyLabel="a"
            android:keyWidth="9%p"
            android:horizontalGap="5.5%p">

        </Key>
        <Key
            android:codes="115"
            android:keyLabel="s"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="100"
            android:keyLabel="d"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="102"
            android:keyLabel="f"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="103"
            android:keyLabel="g"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="104"
            android:keyLabel="h"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="106"
            android:keyLabel="j"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="107"
            android:keyLabel="k"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="108"
            android:keyLabel="l"
            android:keyWidth="9%p"
            android:horizontalGap="1%p">

        </Key>
    </Row>
    <Row android:verticalGap="1%p">
        <Key
            android:codes="-1"
            android:keyLabel="大写"
            android:keyWidth="17%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="122"
            android:keyLabel="z"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="120"
            android:keyLabel="x"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="99"
            android:keyLabel="c"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="118"
            android:keyLabel="v"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="98"
            android:keyLabel="b"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="110"
            android:keyLabel="n"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="109"
            android:keyLabel="m"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="-5"
            android:isRepeatable="true"
            android:keyWidth="17%p"
            android:horizontalGap="1%p">

        </Key>
    </Row>
    <Row>
        <Key
            android:codes="-2"
            android:keyLabel="123"
            android:keyWidth="20%p"
            android:horizontalGap="1%p">

        </Key>
        <Key
            android:codes="32"
            android:keyLabel="space"
            android:keyWidth="48%p"
            android:horizontalGap="5%p">

        </Key>
        <Key
            android:codes="-4"
            android:keyLabel="完成"
            android:keyWidth="20%p"
            android:horizontalGap="5%p">

        </Key>
    </Row>
</Keyboard>

《二》创建IKeyboardView类并继承KeyboardView类,设置键盘布局（数字和字母）

public class IKeyBoardView extends KeyboardView implements KeyboardView.OnKeyboardActionListener {
    
    

    public IIKeyBoardView(Context context, AttributeSet attrs) {
    
    
        super(context, attrs);
        init();
    }

    public IKeyBoardView(Context context, AttributeSet attrs, int defStyleAttr) {
    
    
        super(context, attrs, defStyleAttr);
        init();
    }

    public IIKeyBoardView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
    
    
        super(context, attrs, defStyleAttr, defStyleRes);
        init();
    }

    /**
     * 数字键盘
     */
    private Keyboard keyboardNumber;
    /**
     * 字母键盘
     */
    private Keyboard keyboardLetter;
    //绑定的输入框
    private EditText mEditText;

    /**
     * 是否发生键盘切换
     */
    private boolean changeLetter = false;

    /**
     * 是否为大写
     */
    private boolean isCapital = false;
     private List<Integer> noLists = new ArrayList<>();


    private int[] arrays = new int[]{
    
    Keyboard.KEYCODE_SHIFT, Keyboard.KEYCODE_MODE_CHANGE,
            Keyboard.KEYCODE_CANCEL, Keyboard.KEYCODE_DONE, Keyboard.KEYCODE_DELETE,
            Keyboard.KEYCODE_ALT, 32};

    //初始化
    private void init(){
    
    
        keyboardNumber = new Keyboard(getContext(), R.xml.keyboard_num);
        keyboardLetter = new Keyboard(getContext(), R.xml.keyboard_letter);
        //设置一些不需要预览的键位
        for (int i = 0; i < arrays.length; i++) {
    
    
            noLists.add(arrays[i]);
        }
        //默认使用数字键盘
        setKeyboard(keyboardNumber);
        //是否启用预览
        setPreviewEnabled(true);
        //键盘动作监听
        setOnKeyboardActionListener(this);
    }

    @Override
    public void onPress(int primaryCode) {
    
    

    }

    @Override
    public void onRelease(int primaryCode) {
    
    

    }

    @Override
    public void onKey(int primaryCode, int[] keyCodes) {
    
    

    }

    @Override
    public void onText(CharSequence text) {
    
    

    }

    @Override
    public void swipeLeft() {
    
    

    }

    @Override
    public void swipeRight() {
    
    

    }

    @Override
    public void swipeDown() {
    
    

    }

    @Override
    public void swipeUp() {
    
    

    }
}

《三》 处理自定义键盘按键的点击事件以及预览，并实现数字和字母键盘(包括大小写)之间的切换

核心代码onKey方法（设置键盘输入）

//在onKey回调中的代码
Editable editable = mEditText.getText();
        int start = mEditText.getSelectionStart();
        switch (primaryCode) {
    
    
            case Keyboard.KEYCODE_DELETE://删除
                if (editable != null && editable.length() > 0 && start > 0) {
    
    
                    editable.delete(start - 1, start);
                }
                break;
            case Keyboard.KEYCODE_MODE_CHANGE://字母键盘与数字键盘切换
                    changeKeyBoard(!changeLetter);
                break;
            case Keyboard.KEYCODE_DONE://完成
                changeKeyBoard(!changeLetter);
                break;
            case Keyboard.KEYCODE_SHIFT://大小写切换
                changeCapital(!isCapital);
                setKeyboard(keyboardLetter);
                break;
            default:
                    editable.insert(start, Character.toString((char) primaryCode));
                break;
        }

还有几个必要的方法附上

	/**
     * 切换键盘大小写
     */
    private void changeCapital(boolean b) {
    
    
            isCapital = b;
            List<Keyboard.Key> lists = keyboardLetter.getKeys();
            for (Keyboard.Key key : lists) {
    
    
                if (key.label != null && isKey(key.label.toString())) {
    
    
                    if (isCapital) {
    
    
                        key.label = key.label.toString().toUpperCase();
                        key.codes[0] = key.codes[0] - 32;
                    } else {
    
    
                        key.label = key.label.toString().toLowerCase();
                        key.codes[0] = key.codes[0] + 32;
                    }
                } else if (key.label != null && key.label.toString().equals("小写")) {
    
    
                    key.label = "大写";
                } else if (key.label != null && key.label.toString().equals("大写")) {
    
    
                    key.label = "小写";
                }
            }
    }

 	/**
     * 判断此key是否正确，且存在 * * @param key * @return
     */
    private boolean isKey(String key) {
    
    
        String lowercase = "abcdefghijklmnopqrstuvwxyz";
        if (lowercase.indexOf(key.toLowerCase()) > -1) {
    
    
            return true;
        }
        return false;
    }

	/**
     * 切换键盘类型
     */
    private void changeKeyBoard(boolean b) {
    
    
        changeLetter = b;
        if (b) {
    
    
            setKeyboard(keyboardLetter);
        } else {
    
    
            setKeyboard(keyboardNumber);
        }
    }

/**
     * 判断是否需要预览Key
     *
     * @param primaryCode keyCode
     */
    private void canShowPreview(int primaryCode) {
    
    
        if (noLists.contains(primaryCode)) {
    
    
            setPreviewEnabled(false);
        } else {
    
    
            setPreviewEnabled(true);
        }
    }

	//设置需要绑定的EditView
	public void setmEditText(EditText mEditText) {
    
    
        this.mEditText = mEditText;
    }

《四》 绑定EditText，并且屏蔽系统键盘（实现点击切换绑定多个EditText）

这块我屏蔽键盘的方式是比较粗暴的，直接在EditTextView当中设置了屏蔽焦点，这样的同时会让EditTextView丢失光标

public class IEditText extends AppCompatEditText {
    
    
    private IKeyboardView mIKeyboardView;
    public IEditText(@NonNull Context context) {
    
    
        super(context);
        init();
    }

    public IEditText(@NonNull Context context, @Nullable AttributeSet attrs) {
    
    
        super(context, attrs);
        init();
    }

    public IEditText(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
    
    
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
    
    
        setInputType(InputType.TYPE_NULL);
    }

    //绑定键盘
    public void setmIKeyboardView(IKeyboardView mIKeyboardView) {
    
    
        this.mIKeyboardView = mIKeyboardView;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
    
    
        //按下时绑定当前的EditText
        if (event.getAction() == MotionEvent.ACTION_DOWN){
    
    
            if (mIKeyboardView!=null){
    
    
                mIKeyboardView.setEditText(this);
            }
        }
        return super.onTouchEvent(event);
    }
    
}

《五》. 使用

例如：两个EditTextView一个自定义键盘，因为太简单我就不放出布局代码了(占位置) 就看看咱是如何绑定的

public class MainActivity extends AppCompatActivity {
    
    

    private static final String TAG = "MainActivity:";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
    
    
        super.onCreate(savedInstanceState);
        MainActivityBinding binding = DataBindingUtil.setContentView(this, R.layout.main_activity);


        //默认绑定一个EditTextView
        binding.viewKeyboard.setEditText(binding.ed1);
        //点击时切换绑定键盘
        binding.ed1.setmIKeyboardView(binding.viewKeyboard);
        binding.ed2.setmIKeyboardView(binding.viewKeyboard);
    }

}

4.KeyboardView,keyboard,Key,Row属性解释：

• Keyboard
  
• Row
  
• Key
  
• KeyboardView
  ![在这里插入图片描述](https://img-blog.csdnimg.cn/1e5efd3bbb8248af91cf6beb1ab6b913.png

5.完整代码

https://gitee.com/li-weihao1010/keyboard

6.注意事项

在清单文件（AndroidManifest.xml）中，
activity标签下面不要使用该属性
android:hardwareAccelerated=“true”
不然会导致你键盘卡顿以及点击事件错位问题

6.结尾

如果大家觉得有哪里写得有问题，可以告诉我，一起学习
参考链接