環(huán)信即時(shí)通訊

Q：找不到AsyncTaskCompatl類 NoClassDefFoundError: support/v4/os/AsyncTaskCompat
A：因?yàn)锳syncTaskCompat此類已在API26.0.0以上中被棄用了秩铆，所以需要更改compileSdkVersion最高26，同理targetSdkVersion和其它依賴也需要適當(dāng)降低版本滚粟。

Service里啟動(dòng)Activity延時(shí)問題

Q：Service里監(jiān)聽按鍵然后啟動(dòng)Activity凡壤，大約延時(shí)2-3s左右才啟動(dòng)
A：使用延時(shí)意圖

    intent intent = new Intent(context, AnotherActivity.class);
    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
    try {
        pendingIntent.send(); 
    } catch (PendingIntent.CanceledException e) {
        e.printStackTrace();
    }

getSupportFragmentManager()報(bào)紅

app包下FragmentManager用：
Fragmentmanager fragmentManager=getFragmentManager();
v-4包的FragmentManager用：
FragmentManager fragmentManager=getSupportFragmentManager() 獲取
但是getSupportFragmentManager() 有其運(yùn)用范圍俗扇，只能在部分activity中運(yùn)用铜幽。當(dāng)遇到getSupportFragmentManager() 沒定義的問題時(shí)狮杨，修改下activity為FragmentActivity或者AppCompatActivity橄教。

旋轉(zhuǎn)動(dòng)畫的時(shí)候會(huì)有停頓

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <rotate
        android:duration="2000"
        android:pivotX="50%"
        android:pivotY="50%"
        android:repeatCount="-1"
        android:fromDegrees="0"
        android:toDegrees="359"  />
</set>

        Animation rotateAnimation = AnimationUtils.loadAnimation(this, R.anim.rotate_anim);
        //解決旋轉(zhuǎn)有停頓
        LinearInterpolator lir = new LinearInterpolator();
        rotateAnimation.setInterpolator(lir);
        mIvLoading.startAnimation(rotateAnimation);

Error: Program type already present: android.support.v4.app.INotificationSideChannel

當(dāng)項(xiàng)目使用API28對應(yīng)的是android9.0，當(dāng)AndroidStudio運(yùn)行項(xiàng)目的時(shí)候出現(xiàn)編譯錯(cuò)誤：Error: Program type already present: android.support.v4.app.INotificationSideChannel，這意思是v4包沖突了比吭。
首先，查找一下自己的文件里是否存在v4包重復(fù)的赏表，搜索之后發(fā)現(xiàn)沒有出現(xiàn)重復(fù)，針對這個(gè)問題查看了網(wǎng)上一些資料间狂，發(fā)現(xiàn)這個(gè)問題是AndroidX版本引起的。有以下兩種解決方法：

1纺弊、Refactor-->Migrate to AndroidX

2、向gradle.properties添加以下內(nèi)容：
android.enableJetifier=true
android.useAndroidX=true

Android與AndroidX包重復(fù)問題詳情可查看這篇文章：http://www.reibang.com/p/1466ebefe4d0
如果SDK不是28的版本焰望，可在Terminal窗口復(fù)制命令gradlew clean build --stacktrace去查看詳細(xì)信息針對性去解決問題~

zip4j jar包使用中遇到解壓文件名字部分出現(xiàn)亂碼

ZipFile zipFile = new ZipFile(zipfilenow.getAbsolutePath());
zipFile.setFileNameCharset(getCharset(zipfilenow.getPath()));

/**
     * 判斷文件的編碼格式
     *
     * @param fileName
     * @return
     */
    public static String getCharset(String fileName) {
        BufferedInputStream bis = null;
        String charset = "GBK";
        byte[] first3Bytes = new byte[3];
        try {
            boolean checked = false;
            bis = new BufferedInputStream(new FileInputStream(fileName));
            bis.mark(0);
            int read = bis.read(first3Bytes, 0, 3);
            if (read == -1)
                return charset;
            if (first3Bytes[0] == (byte) 0xFF && first3Bytes[1] == (byte) 0xFE) {
                charset = "UTF-16LE";
                checked = true;
            } else if (first3Bytes[0] == (byte) 0xFE
                    && first3Bytes[1] == (byte) 0xFF) {
                charset = "UTF-16BE";
                checked = true;
            } else if (first3Bytes[0] == (byte) 0xEF
                    && first3Bytes[1] == (byte) 0xBB
                    && first3Bytes[2] == (byte) 0xBF) {
                charset = "UTF-8";
                checked = true;
            }
            bis.mark(0);
            if (!checked) {
                while ((read = bis.read()) != -1) {
                    if (read >= 0xF0)
                        break;
                    if (0x80 <= read && read <= 0xBF) // 單獨(dú)出現(xiàn)BF以下的捆姜，也算是GBK
                        break;
                    if (0xC0 <= read && read <= 0xDF) {
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) // 雙字節(jié) (0xC0 - 0xDF)
                            // (0x80 - 0xBF),也可能在GB編碼內(nèi)
                            continue;
                        else
                            break;
                    } else if (0xE0 <= read && read <= 0xEF) {// 也有可能出錯(cuò)，但是幾率較小
                        read = bis.read();
                        if (0x80 <= read && read <= 0xBF) {
                            read = bis.read();
                            if (0x80 <= read && read <= 0xBF) {
                                charset = "UTF-8";
                                break;
                            } else
                                break;
                        } else
                            break;
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (bis != null) {
                try {
                    bis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        return charset;
    }