一些平时可能会用到的

一些平时可能会用到的，不定期更新

• 判断sdk版本大于6.0

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){}
  

• 请求运行时权限

    private void requestPermission() {
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.WRITE_EXTERNAL_STORAGE)
                != PackageManager.PERMISSION_GRANTED) {
  
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                    1001);
        } else {
           //已经拥有权限
        }
    }
  

• 根据包名打开相关的app

   Intent intentForPackage = getPackageManager().getLaunchIntentForPackage("yourAppPackageName");
   startActivity(intentForPackage);
  

• 根据包名和Activity名称打开对应的Activity

   Intent intent = new Intent();
   intent.setClassName("com.rk_itvui.settings", "com.rk_itvui.settings.network_settingnew");
  

• 获取定位城市

    mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    Location location = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
    double latitude = location.getLatitude();
    double longitude = location.getLongitude();
  
    Geocoder ge = new Geocoder(this);
    addList = ge.getFromLocation(latitude, longitude, 1);
    Address ad = addList.get(i);
    //国家和城市
    String s = ad.getCountryName() + ";" + ad.getLocality() +";" + ad.getSubLocality();
  

• 模拟键盘输入

    instrumentation = new Instrumentation();
    int keycode = 7;
    instrumentation.sendKeyDownUpSync(keycode);
  

• 隐藏底部NavigationBar

    private void hideNavicationView() {
        WindowManager.LayoutParams params = getWindow().getAttributes();
        params.systemUiVisibility = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_IMMERSIVE;
        getWindow().setAttributes(params);
    }
  

• 获取屏幕相关信息

    private void getDisplayMetrics() {
        DisplayMetrics metric = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(metric);
        // 屏幕宽度（像素）
        int width = metric.widthPixels;
        // 屏幕高度（像素）
        int height = metric.heightPixels;
        // 屏幕密度比（1.0 / 1.5 / 2.0）
        float density = metric.density;
        // 屏幕密度DPI（160 / 240 / 320）
        int densityDpi = metric.densityDpi;
        String info = "机顶盒型号: " + android.os.Build.MODEL + "," +
                "\nSDK版本:" + android.os.Build.VERSION.SDK + "," +
                "\n系统版本:"+ android.os.Build.VERSION.RELEASE +
                "\n屏幕宽度（像素）: " + width +
                "\n屏幕高度（像素）: " + height +
                "\n屏幕密度比:  " + density +
                "\n屏幕密度DPI: " + densityDpi;
        Log.d("System INFO", info);
  
    }
  

• 获取所有存储卡和u盘的目录

    private  void  getStroage(){
        String[] result = null;
        StorageManager storageManager = (StorageManager)getSystemService(Context.STORAGE_SERVICE);
        try {
            Method method = StorageManager.class.getMethod("getVolumePaths");
            method.setAccessible(true);
            try {
                result =(String[])method.invoke(storageManager);
            } catch (InvocationTargetException e) {
                e.printStackTrace();
            }
            for (int i = 0; i < result.length; i++) {
                Log.d(this.getClass().getSimpleName(), "getStroage: " + result[i] + "\n");
                System.out.println("path----> " + result[i]+"\n");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
  

• Android查询指定后缀名的文件

        /**
         * 查询SD卡里所有pdf文件pdf可以替换
         */
        private void queryFiles() {
            String[] projection = new String[]{MediaStore.Files.FileColumns._ID,
                    MediaStore.Files.FileColumns.DATA,
                    MediaStore.Files.FileColumns.SIZE
            };
            Cursor cursor = getContentResolver().query(
                    Uri.parse("content://media/external/file"),
                    projection,
                    MediaStore.Files.FileColumns.DATA + " like ?",
                    new String[]{"%.pdf"},//数组里边更改想要查询的后缀名
                    null);
            if (cursor != null) {
                while (cursor.moveToNext()) {
                    int idindex = cursor
                            .getColumnIndex(MediaStore.Files.FileColumns._ID);
                    int dataindex = cursor
                            .getColumnIndex(MediaStore.Files.FileColumns.DATA);
                    int sizeindex = cursor
                            .getColumnIndex(MediaStore.Files.FileColumns.SIZE);
                    String id = cursor.getString(idindex);
                    String path = cursor.getString(dataindex);
                    String size = cursor.getString(sizeindex);
  
                    Log.d(TAG, "id = " + id + "\n"
                            + "路径 = " + path + "\n"
                            + "size = " + size);
                }
                cursor.close();
            }
  

• 将view保存为bitmap

    private Bitmap createBitmapFromView(View view) {
        Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.RGB_565);
        Canvas canvas = new Canvas(bitmap);
        view.layout(view.getLeft(), view.getTop(), view.getRight(), view.getBottom());
        // Draw background
        Drawable bgDrawable = view.getBackground();
        if (bgDrawable != null) {
            bgDrawable.draw(canvas);
        } else {
            canvas.drawColor(Color.WHITE);
        }
        // Draw view to canvas
        view.draw(canvas);
        return bitmap;
    }
  

• 静默安装,需要root权限

    /**
     * 静默安装,通过PM命令
     *
     * @param apkFilePath apk文件路径
     * @return true表示安装成功，否则返回false
     */
    public static boolean silentInstall(String apkFilePath) {
        boolean isInstallOk = false;
        if (isSupportSilentInstall()) {
            DataOutputStream dataOutputStream = null;
            BufferedReader bufferedReader = null;
            try {
                Process process = Runtime.getRuntime().exec("su");
                dataOutputStream = new DataOutputStream(process.getOutputStream());
                String command = "pm install -r " + apkFilePath + "\n";
                dataOutputStream.write(command.getBytes(Charset.forName("utf-8")));
                dataOutputStream.flush();
                dataOutputStream.writeBytes("exit\n");
                dataOutputStream.flush();
                process.waitFor();
                bufferedReader = new BufferedReader(new InputStreamReader(process.getErrorStream()));
                StringBuilder msg = new StringBuilder();
                String line;
                while ((line = bufferedReader.readLine()) != null) {
                    msg.append(line);
                }
                if (msg.toString().contains("Success")) {
                    isInstallOk = true;
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (dataOutputStream != null) {
                    try {
                        dataOutputStream.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                if (bufferedReader != null) {
                    try {
                        bufferedReader.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
  
            }
        }
        return isInstallOk;
    }
  

• 连续点击五次出现当前版本号
  能够实现n此事件的点击，只需将数组长度定义为n个长度。

    long[] mHits = new long[5];
    private View.OnClickListener mShowVersionCodeListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //每点击一次 实现左移一格数据
            System.arraycopy(mHits, 1, mHits, 0, mHits.length - 1);
            //给数组的最后赋当前时钟值
            mHits[mHits.length - 1] = SystemClock.uptimeMillis();
            //当0出的值大于当前时间-500时  证明在500秒内点击了2次
            if(mHits[0] > SystemClock.uptimeMillis() - 2000){
                ToastUtils.showLong("当前版本:"+AppUtils.getAppVersionCode());
            }
        }
    };
  

• 发送广播让Android系统将新加的图片加入图片库

    private void sendImageAddBroadcast() {
        //imageFileList 文件的集合
        if (imageFileList != null) {
            for (int i = 0; i < imageFileList.size(); i++) {
                // 其次把文件插入到系统图库
                File file = imageFileList.get(i);
                try {
                    MediaStore.Images.Media.insertImage(mContext.getContentResolver(),
                            file.getAbsolutePath(), file.getName(), null);
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                }
                // 最后通知图库更新
                mContext.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://" + file.getPath())));
  
            }
        }
    }
  

• 将drawable转换为bitmap

    public static Bitmap drawable2Bitmap(Drawable drawable) {
        if (drawable instanceof BitmapDrawable) {
            return ((BitmapDrawable) drawable).getBitmap();
        } else if (drawable instanceof NinePatchDrawable) {
            Bitmap bitmap = Bitmap
                    .createBitmap(
                            drawable.getIntrinsicWidth(),
                            drawable.getIntrinsicHeight(),
                            drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                                    : Bitmap.Config.RGB_565);
            Canvas canvas = new Canvas(bitmap);
            drawable.setBounds(0, 0, drawable.getIntrinsicWidth(),
                    drawable.getIntrinsicHeight());
            drawable.draw(canvas);
            return bitmap;
        } else {
            return null;
        }
    }
  

或者drawable是个资源文件
Resources res = getResources();
Bitmap bmp = BitmapFactory.decodeResource(res, R.drawable.pic);

• 将bitmap转换为drawable

    public static   Drawable bitmap2Drawable(Bitmap bitmap) {
            return new BitmapDrawable(bitmap);
        }
  

• 获取apk文件的icon

    public static Drawable getApkIcon(Context context, String apkPath) {
        PackageManager pm = context.getPackageManager();
        PackageInfo info = pm.getPackageArchiveInfo(apkPath,
                PackageManager.GET_ACTIVITIES);
        if (info != null) {
            ApplicationInfo appInfo = info.applicationInfo;
            appInfo.sourceDir = apkPath;
            appInfo.publicSourceDir = apkPath;
            try {
                return appInfo.loadIcon(pm);
            } catch (OutOfMemoryError e) {
                Log.e("ApkIconLoader", e.toString());
            }
        }
        return null;
    }
  

• 动态用代码改变图片的颜色(图片必须为单一颜色,不需要改变的地方为透明色)

       private Drawable getTintDrawable(Context context, @DrawableRes int image, int color) {
           Drawable drawable = ContextCompat.getDrawable(context, image);
           Drawable.ConstantState constantState = drawable.getConstantState();
           Drawable newDrawable = DrawableCompat.wrap(constantState == null ? drawable : constantState.newDrawable()).mutate();
           DrawableCompat.setTint(newDrawable, color);
           return newDrawable;
       }
  

• 保留float 后两位小数

DecimalFormat decimalFormat=new DecimalFormat(".00");//构造方法的字符格式这里如果小数不足2位,会以0补足.
String format = decimalFormat.format(rate);

Android 7.0（Nougat，牛轧糖）开始，Android更改了对用户安装证书的默认信任行为，应用程序「只信任系统级别的CA」。

对此，如果是自己写的APP想抓HTTPS的包，可以在 res/xml目录下新建一个network_security_config.xml 文件，复制粘贴如下内容：

    <base-config cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system" overridePins="true" /> <!--信任系统证书-->
            <certificates src="user" overridePins="true" /> <!--信任用户证书-->
        </trust-anchors>
    </base-config>
</network-security-config>

复制代码接着AndroidManifest.xml文件中新增networkSecurityConfig属性引用xml文件，如下：

<?xml version="1.0" encoding="utf-8"?>
<manifest ... >
    <application android:networkSecurityConfig="@xml/network_security_config"
    ... >
    ...
    </application>
</manifest>

复制代码调试期为了方便自己抓包可以加上，发版本的时候，记得删掉哦！！！

调取相机拍照,并获取照片路径

                SPUtils.getInstance().put("path",mFilePath);
                File outFile = new File(mFilePath);
                Uri uri = FileProvider.getUriForFile(
                        SavePunchAvatarActivity.this,
                        "com.jy.feng.fileProvider",
                        outFile);
                //拍照
                Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
                startActivityForResult(intent, REQUEST_CODE);