概述

　　在项目开发中遇到一个需求，”只要数字键盘的输入，仅仅有大写字母的输入，某些输入法总是会提示更新，弹出广告等“，使得我们需要自定义输入。

关联到的知识　

KeyboardView 一个视图对象，展示了键盘。它需要关联到一个 Keyboard对象才能展示。
Keyboard 键盘对象，通过加载xml的配置获得键盘的排列。
xml 文件键盘描述一个xml文件，放置在 xml 资源文件夹下，描述了显示的键盘按钮，和排列，键盘宽度和高度等。

具体实现

　　准备xml键盘描述文件

　　　　在xml文件夹下创建文件，下面的代码中使用 “ 33%p” 这样的单位指定一定的百分比，以适配屏幕，详细内容如下：

<?xml version="1.0" encoding="UTF-8"?><!-- 数字键盘 -->

<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"

    android:horizontalGap="0dp"

    android:keyHeight="61dp"

    android:keyWidth="33%p"

    android:verticalGap="0dp">

    <Row>

        <Key

            android:codes="49"

            android:keyEdgeFlags="left"

            android:keyLabel="1" />

        <Key

            android:codes="50"

            android:keyLabel="2" />

        <Key

            android:codes="51"

            android:keyLabel="3" />

    </Row>

    <Row>

        <Key

            android:codes="52"

            android:keyEdgeFlags="left"

            android:keyLabel="4" />

        <Key

            android:codes="53"

            android:keyLabel="5" />

        <Key

            android:codes="54"

            android:keyLabel="6" />

    </Row>

    <Row>

        <Key

            android:codes="55"

            android:keyEdgeFlags="left"

            android:keyLabel="7" />

        <Key

            android:codes="56"

            android:keyLabel="8" />

        <Key

            android:codes="57"

            android:keyLabel="9" />

    </Row>

    <Row>

        <Key

            android:codes="48"

            android:keyEdgeFlags="left"

            android:keyLabel="0" />

        <Key

            android:codes="-5"

            android:isRepeatable="true"

            android:keyIcon="@drawable/keyboard_delete"

            android:keyWidth="66%p" />

    </Row>

</Keyboard>

　　创建Keyboard对象

　　　　要先配置好xml文件，在构造方法里传入上面的xml文件

 this.keyboard = new Keyboard(mActivity, R.xml.small_keyboard);

　　构造KeyboardView

　　　　keyboardView 对象可以在 xml 中描述，类似下面这样

<android.inputmethodservice.KeyboardView

        android:id="@+id/keyboard_view"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_gravity="center"

        android:background="@android:color/transparent"

        android:focusable="true"

        android:focusableInTouchMode="true"

        android:keyBackground="@drawable/keyboard_key"

        android:keyTextColor="@color/white"

        android:keyTextSize="@dimen/sp_32"

        android:visibility="visible" />

　　　　获得 KeyboardView并进行配置，需要关联到具体的 keyboard 对象

        KeyboardView keyboardView = (KeyboardView) viewContainer.findViewById(R.id.keyboard_view);

        this.keyboardView = keyboardView;

        this.keyboardView.setKeyboard(keyboard);

        this.keyboardView.setEnabled(true);

        this.keyboardView.setPreviewEnabled(false);

        this.keyboardView.setOnKeyboardActionListener(listener2);

　　隐藏系统自带的键盘

　　　　　　根据android系统的版本的不同，有不同的方法，需要利用反射，见代码：

 /**

     * 隐藏系统键盘

     *

     * @param editText

     */

    public static void hideSystemSofeKeyboard(EditText editText) {

        int sdkInt = Build.VERSION.SDK_INT;

        if (sdkInt >= 11) {

            try {

                Class<EditText> cls = EditText.class;

                Method setShowSoftInputOnFocus;

                setShowSoftInputOnFocus = cls.getMethod("setShowSoftInputOnFocus", boolean.class);

                setShowSoftInputOnFocus.setAccessible(true);

                setShowSoftInputOnFocus.invoke(editText, false);

            } catch (SecurityException e) {

                e.printStackTrace();

            } catch (NoSuchMethodException e) {

                e.printStackTrace();

            } catch (Exception e) {

                e.printStackTrace();

            }

        } else {

            editText.setInputType(InputType.TYPE_NULL);

        }

    }

　　从底部弹出键盘

　　输入法需要从页面底部向上弹出，需要一个过渡动画，android每个页面都有一个window,window包含了一个getDecorView 根视图，我们要把键盘的视图添加到这个根视图下，配合动画出现键盘。

    public void showSoftKeyboard() {

        if (viewContainer == null) {

            viewContainer = mActivity.getLayoutInflater().inflate(R.layout.keyboardview_layout, null);

        } else {

            if (viewContainer.getParent() != null)

                return;

        }

        FrameLayout frameLayout = (FrameLayout) mActivity.getWindow().getDecorView();

        KeyboardView keyboardView = (KeyboardView) viewContainer.findViewById(R.id.keyboard_view);

        this.keyboardView = keyboardView;

        this.keyboardView.setKeyboard(keyboard);

        this.keyboardView.setEnabled(true);

        this.keyboardView.setPreviewEnabled(false);

        this.keyboardView.setOnKeyboardActionListener(listener2);

        FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.WRAP_CONTENT);

        lp.gravity = Gravity.BOTTOM;

        frameLayout.addView(viewContainer, lp);

        //viewContainer.setVisibility(View.GONE);

        viewContainer.setAnimation(AnimationUtils.loadAnimation(mActivity, R.anim.down_to_up));

    }

完整的代码如下：

package vir56k.democustomkeyboard;

import android.app.Activity;

import android.inputmethodservice.Keyboard;

import android.inputmethodservice.KeyboardView;

import android.inputmethodservice.KeyboardView.OnKeyboardActionListener;

import android.os.Build;

import android.text.Editable;

import android.text.InputType;

import android.text.TextUtils;

import android.view.Gravity;

import android.view.View;

import android.view.ViewGroup;

import android.view.animation.AnimationUtils;

import android.widget.EditText;

import android.widget.FrameLayout;

import java.lang.reflect.Method;

public class PopupKeyboardUtil {

    private Activity mActivity;

    private KeyboardView keyboardView;

    private Keyboard keyboard;// 全键盘包括数字和字母

    private EditText editText1;

    public PopupKeyboardUtil(Activity mActivity) {

        this.mActivity = mActivity;

        this.keyboard = new Keyboard(mActivity, R.xml.small_keyboard);

    }

    public void attachTo(EditText editText, boolean isAuto) {

        this.editText1 = editText;

        hideSystemSofeKeyboard(this.editText1);

        setAutoShowOnFocs(isAuto);

    }

    public void setAutoShowOnFocs(boolean enable) {

        if (editText1 == null)

            return;

        if (enable)

            editText1.setOnFocusChangeListener(onFocusChangeListener1);

        else

            editText1.setOnFocusChangeListener(null);

    }

    View.OnFocusChangeListener onFocusChangeListener1 = new View.OnFocusChangeListener() {

        @Override

        public void onFocusChange(View v, boolean hasFocus) {

            if (hasFocus)

                showSoftKeyboard();

            else

                hideSoftKeyboard();

        }

    };

    View viewContainer;

    public void showSoftKeyboard() {

        if (viewContainer == null) {

            viewContainer = mActivity.getLayoutInflater().inflate(R.layout.keyboardview_layout, null);

        } else {

            if (viewContainer.getParent() != null)

                return;

        }

        FrameLayout frameLayout = (FrameLayout) mActivity.getWindow().getDecorView();

        KeyboardView keyboardView = (KeyboardView) viewContainer.findViewById(R.id.keyboard_view);

        this.keyboardView = keyboardView;

        this.keyboardView.setKeyboard(keyboard);

        this.keyboardView.setEnabled(true);

        this.keyboardView.setPreviewEnabled(false);

        this.keyboardView.setOnKeyboardActionListener(listener2);

        FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.WRAP_CONTENT);

        lp.gravity = Gravity.BOTTOM;

        frameLayout.addView(viewContainer, lp);

        //viewContainer.setVisibility(View.GONE);

        viewContainer.setAnimation(AnimationUtils.loadAnimation(mActivity, R.anim.down_to_up));

    }

    public void hideSoftKeyboard() {

        if (viewContainer != null && viewContainer.getParent() != null) {

            ((ViewGroup) viewContainer.getParent()).removeView(viewContainer);

        }

    }

    public boolean isShowing() {

        if (viewContainer == null)

            return false;

        return viewContainer.getVisibility() == View.VISIBLE;

    }

    /**

     * 隐藏系统键盘

     *

     * @param editText

     */

    public static void hideSystemSofeKeyboard(EditText editText) {

        int sdkInt = Build.VERSION.SDK_INT;

        if (sdkInt >= 11) {

            try {

                Class<EditText> cls = EditText.class;

                Method setShowSoftInputOnFocus;

                setShowSoftInputOnFocus = cls.getMethod("setShowSoftInputOnFocus", boolean.class);

                setShowSoftInputOnFocus.setAccessible(true);

                setShowSoftInputOnFocus.invoke(editText, false);

            } catch (SecurityException e) {

                e.printStackTrace();

            } catch (NoSuchMethodException e) {

                e.printStackTrace();

            } catch (Exception e) {

                e.printStackTrace();

            }

        } else {

            editText.setInputType(InputType.TYPE_NULL);

        }

    }

    private OnKeyboardActionListener listener2 = new OnKeyboardActionListener() {

        @Override

        public void swipeUp() {

        }

        @Override

        public void swipeRight() {

        }

        @Override

        public void swipeLeft() {

        }

        @Override

        public void swipeDown() {

        }

        @Override

        public void onText(CharSequence text) {

        }

        @Override

        public void onRelease(int primaryCode) {

        }

        @Override

        public void onPress(int primaryCode) {

        }

        @Override

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

            if (editText1 != null) {

                keyCode_delect(primaryCode, editText1);

            }

            keyboardView.postInvalidate();

        }

    };

    /**

     * 判断回退键 和大小写切换

     *

     * @param primaryCode

     * @param edText

     */

    private void keyCode_delect(int primaryCode, EditText edText) {

        Editable editable = edText.getText();

        int start = edText.getSelectionStart();

        if (primaryCode == Keyboard.KEYCODE_DELETE) {// 回退

            if (edText.hasFocus()) {

                if (!TextUtils.isEmpty(editable)) {

                    if (start > 0) {

                        editable.delete(start - 1, start);

                    }

                }

            }

        } else if (primaryCode == Keyboard.KEYCODE_SHIFT) {// 大小写切换

            keyboardView.setKeyboard(keyboard);

        } else {

            if (edText.hasFocus()) {

                editable.insert(start, Character.toString((char) primaryCode));

            }

        }

    }

}

功能完成后，具体调用的演示：

package vir56k.democustomkeyboard;

import android.app.Activity;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.view.View;

import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    EditText edittext1;

    PopupKeyboardUtil smallKeyboardUtil;

    private View viewContainer;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        edittext1 = (EditText) findViewById(R.id.edittext1);

        smallKeyboardUtil = new PopupKeyboardUtil(self());

        smallKeyboardUtil.attachTo(edittext1, false);

        //smallKeyboardUtil.setAutoShowOnFocs(false);

    }

    public void onClickView(View view) {

        if (view.getId() == R.id.btn1)

            smallKeyboardUtil.showSoftKeyboard();

        if (view.getId() == R.id.btn2)

            smallKeyboardUtil.hideSoftKeyboard();

    }

    private Activity self() {

        return this;

    }

}

完整的代码下载：

https://github.com/vir56k/demo/tree/master/demo.customkeyboard

巴特西

android开发(45) 自定义软键盘（输入法）

概述