工具类

1.控制软键盘

import android.app.Activity;
import android.content.Context;
import android.graphics.Paint;
import android.preference.PreferenceManager;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.TextView;

public class EmoticonsKeyboardUtils {

    private static final String EXTRA_DEF_KEYBOARDHEIGHT = "DEF_KEYBOARDHEIGHT";
    private static final int DEF_KEYBOARD_HEAGH_WITH_DP = 300;
    private static int sDefKeyboardHeight = -1;

    private static DisplayMetrics getDisplayMetrics(Context context) {
        DisplayMetrics dm = new DisplayMetrics();
        ((Activity) context).getWindowManager().getDefaultDisplay().getMetrics(dm);
        return dm;
    }

    public static int getDisplayWidthPixels(Context context) {
        return getDisplayMetrics(context).widthPixels;
    }

    public static int dip2px(Context context, float dipValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (dipValue * scale + 0.5f);
    }

    public static int px2dip(Context context, float pxValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (pxValue / scale + 0.5f);
    }

    public static int getFontHeight(TextView textView) {
        Paint paint = new Paint();
        paint.setTextSize(textView.getTextSize());
        Paint.FontMetrics fm = paint.getFontMetrics();
        return (int) Math.ceil(fm.bottom - fm.top);
    }

    public static View getRootView(Activity context) {
        return ((ViewGroup) context.findViewById(android.R.id.content)).getChildAt(0);
    }

    public static int getDefKeyboardHeight(Context context) {
        if (sDefKeyboardHeight < 0) {
            sDefKeyboardHeight = dip2px(context, DEF_KEYBOARD_HEAGH_WITH_DP);
        }
        int height = PreferenceManager.getDefaultSharedPreferences(context).getInt(EXTRA_DEF_KEYBOARDHEIGHT, 0);
        return sDefKeyboardHeight = height > 0 && sDefKeyboardHeight != height ? height : sDefKeyboardHeight;
    }

    public static void setDefKeyboardHeight(Context context, int height) {
        if (sDefKeyboardHeight != height) {
            PreferenceManager.getDefaultSharedPreferences(context).edit().putInt(EXTRA_DEF_KEYBOARDHEIGHT, height).commit();
            EmoticonsKeyboardUtils.sDefKeyboardHeight = height;
        }
    }

    public static boolean isFullScreen(final Activity activity) {
        return (activity.getWindow().getAttributes().flags &
                WindowManager.LayoutParams.FLAG_FULLSCREEN) != 0;
    }

    /**
     * 开启软键盘
     * @param et
     */
    public static void openSoftKeyboard(EditText et) {
        if (et != null) {
            et.setFocusable(true);
            et.setFocusableInTouchMode(true);
            et.requestFocus();
            InputMethodManager inputManager = (InputMethodManager) et.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
            inputManager.showSoftInput(et, 0);
        }
    }

    /**
     * 关闭软键盘
     * @param context
     */
    public static void closeSoftKeyboard(Context context) {
        if (context == null || !(context instanceof Activity) || ((Activity) context).getCurrentFocus() == null) {
            return;
        }
        try{
            View view = ((Activity) context).getCurrentFocus();
            InputMethodManager imm = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
            view.clearFocus();
            imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
        } catch (Exception e){
            e.printStackTrace();
        }
    }

    /**
     * 关闭软键盘
     * 当使用全屏主题的时候,XhsEmoticonsKeyBoard屏蔽了焦点.关闭软键盘时,直接指定 closeSoftKeyboard(EditView)
     * @param view
     */
    public static void closeSoftKeyboard(View view) {
        if (view == null || view.getWindowToken() == null) {
            return;
        }
        InputMethodManager imm = (InputMethodManager) view.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
    }
}

2.对于图片的压缩  获取视频的图片

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.media.ExifInterface;
import android.media.MediaMetadataRetriever;
import android.os.Environment;
import android.util.Log;

import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.ref.WeakReference;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Hashtable;
import java.util.Locale;

/**
 * 集合一些图片工具
 *
 * Created by zhuwentao on 2016-07-22.
 */
public class PhotoBitmapUtils {

    /**
     * 存放拍摄图片的文件夹
     */
    private static final String FILES_NAME = "/MyPhoto";
    /**
     * 获取的时间格式
     */
    public static final String TIME_STYLE = "yyyyMMddHHmmss";
    /**
     * 图片种类
     */
    public static final String IMAGE_TYPE = ".png";
    /**
     * 缩减文件的大小
     */
    public static final long FILE_SIZE=200;

    // 防止实例化
    private PhotoBitmapUtils() {
    }
    public static File getimage(String srcPath) {

        BitmapFactory.Options newOpts = new BitmapFactory.Options();
        // 开始读入图片，此时把options.inJustDecodeBounds 设回true了
        newOpts.inJustDecodeBounds = true;
        newOpts.inJustDecodeBounds = false;

        Bitmap bitmap = BitmapFactory.decodeFile(srcPath, newOpts);
        return compressImage(bitmap);
    }

    /**
     * 缩放大小  缩略图
     * */
    public static Bitmap zoomImg(Bitmap bm, int newWidth ,int newHeight){
        // 获得图片的宽高
        int width = bm.getWidth();
        int height = bm.getHeight();
        // 计算缩放比例
        float scaleWidth = ((float) newWidth) / width;
        float scaleHeight = ((float) newHeight) / height;
        // 取得想要缩放的matrix参数
        Matrix matrix = new Matrix();
        matrix.postScale(scaleWidth, scaleHeight);
        // 得到新的图片
        Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, true);
        return newbm;
    }
    public static Bitmap createVideoThumbnail(String filePath)
    {
        Bitmap bitmap = null;
        MediaMetadataRetriever retriever = new MediaMetadataRetriever();
        try
        {
            if (filePath.startsWith("http://")
                    || filePath.startsWith("https://")
                    || filePath.startsWith("widevine://"))
            {
                retriever.setDataSource(filePath, new Hashtable<String, String>());
            }
            else
            {
                retriever.setDataSource(filePath);
            }
            bitmap = retriever.getFrameAtTime(0, MediaMetadataRetriever.OPTION_CLOSEST_SYNC); //retriever.getFrameAtTime(-1);
        }
        catch (IllegalArgumentException ex)
        {
            // Assume this is a corrupt video file
            ex.printStackTrace();
        }
        catch (RuntimeException ex)
        {
            // Assume this is a corrupt video file.
            ex.printStackTrace();
        }
        finally
        {
            try
            {
                retriever.release();
            }
            catch (RuntimeException ex)
            {
                // Ignore failures while cleaning up.
                ex.printStackTrace();
            }
        }

        return bitmap;
    }
    /**
     * 压缩图片（质量压缩）
     * @param bitmap
     */
    public static File compressImage(Bitmap bitmap) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);//质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中
        int options = 100;
        while (baos.toByteArray().length / 1024 > FILE_SIZE) {  //循环判断如果压缩后图片是否大于500kb,大于继续压缩
            baos.reset();//重置baos即清空baos
            options -= 10;//每次都减少10
            bitmap.compress(Bitmap.CompressFormat.JPEG, options, baos);//这里压缩options%，把压缩后的数据存放到baos中
            long length = baos.toByteArray().length;
        }
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");
        Date date = new Date(System.currentTimeMillis());
        String filename = format.format(date);
        File file = new File(Environment.getExternalStorageDirectory(),filename+".png");
        try {
            FileOutputStream fos = new FileOutputStream(file);
            try {
                fos.write(baos.toByteArray());
                fos.flush();
                fos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        return file;
    }

}

3.监听软键盘

window.decorView.addOnLayoutChangeListener {v, left, top, right, down, oldLeft, oldTop, oldRight, oldBottom ->
    val rect = Rect()
    window.decorView.getWindowVisibleDisplayFrame(rect)
    val screenHeight = window.decorView.rootView.height
    val heightDifference = screenHeight - rect.bottom
    val visible = heightDifference > screenHeight / 3

    if (visible) {
       
    } else {
       
    }

}

4.解决CoordinatorLayout 快速拖拽  抖动问题

引入自定义behavior

    app:layout_behavior="org.com.qy.myapplication.CustomBehavior"

import android.content.Context;
import android.support.design.widget.AppBarLayout;
import android.support.design.widget.CoordinatorLayout;
import android.support.v4.view.ViewCompat;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.OverScroller;

import java.lang.reflect.Field;

public class CustomBehavior extends AppBarLayout.Behavior {
    private OverScroller mScroller;
    private static final int TYPE_FLING = 1;

    private boolean isFlinging;
    private boolean shouldBlockNestedScroll;
    public CustomBehavior() {
    }

    public CustomBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
        getParentScroller(context);
    }

    /**
     * 反射获得滑动属性。
     *
     * @param context
     */
    private void getParentScroller(Context context) {
        if (mScroller != null) return;
        mScroller = new OverScroller(context);
        try {
            Class<?> reflex_class = getClass().getSuperclass().getSuperclass();//父类AppBarLayout.Behavior父类的父类HeaderBehavior
            Field fieldScroller = reflex_class.getDeclaredField("mScroller");
            fieldScroller.setAccessible(true);
            fieldScroller.set(this, mScroller);
        } catch (Exception e) {
        }
    }

    //fling上滑appbar然后迅速fling下滑recycler时, HeaderBehavior的mScroller并未停止, 会导致上下来回晃动
    @Override
    public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dx, int dy, int[] consumed, int type) {
        if (mScroller != null) { //当recyclerView 做好滑动准备的时候 直接干掉Appbar的滑动
            if (mScroller.computeScrollOffset()) {
                mScroller.abortAnimation();
            }
        }
        if (type == ViewCompat.TYPE_NON_TOUCH && getTopAndBottomOffset() == 0) { //recyclerview的惯性比较大 ,会顶在头部一会儿, 到头直接干掉它的滑动
            ViewCompat.stopNestedScroll(target, type);
        }
        if (type == TYPE_FLING) {
            isFlinging = true;
        }
        if (!shouldBlockNestedScroll) {
            super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
        }
        super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed, type);
    }

    @Override
    public boolean onTouchEvent(CoordinatorLayout parent, AppBarLayout child, MotionEvent e) {

        switch (e.getActionMasked()) {
            case MotionEvent.ACTION_DOWN:
                break;
        }

        return super.onTouchEvent(parent, child, e);
    }
    @Override
    public boolean onInterceptTouchEvent(CoordinatorLayout parent, AppBarLayout child, MotionEvent ev) {

        shouldBlockNestedScroll = false;
        if (isFlinging) {
            shouldBlockNestedScroll = true;
        }
        return super.onInterceptTouchEvent(parent, child, ev);
    }



    @Override
    public void onNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout child, View target, int dxConsumed, int dyConsumed, int
            dxUnconsumed, int dyUnconsumed, int type) {

        if (!shouldBlockNestedScroll) {
            super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, type);
        }
    }

    @Override
    public void onStopNestedScroll(CoordinatorLayout coordinatorLayout, AppBarLayout abl, View target, int type) {
        super.onStopNestedScroll(coordinatorLayout, abl, target, type);
        isFlinging = false;
        shouldBlockNestedScroll = false;
    }
}