Android开发(45) 自定义软键盘

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：

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

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 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：

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 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;
    }
}

代码下载：

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