android开发中积累的小知识

From: http://blog.csdn.net/zhou123shao/article/details/22926367
一：开机logo ，在根路径7627a_splash下把图片放入，运行splash.sh文件

然后再把splash.txt中的值复制粘帖在bootable/bootloader/lk/target/项目名/include/target/的splash.h文件中

再make aboot

把out/target/product/项目名/下面(emmc_appsboot.mbn,emmc_appsboothd.mbn)这个是针对与emmc,或者是(appsboot.mbn,appsboothd.mbn)这个是针对nand。把这2个文件考出来，在window下用qts烧写进去。

二：修改开关机动画

把***好的bootanimation.zip和shutdownanimation.zip放到 /system/core/rootdir/项目名/。

可以直接push到机器的system/media下面，重启就可以看到效果

三：判断项目名

import android.os.SystemProperties;

private boolean mIsA100 = "msm7627a_v12_a100".equals(SystemProperties.get("ro.product.name"));

if("1".equals(SystemProperties.get("persist.sys.emmcsdcard.enabled")))这是把内存设在为内部存储

在cpp文件中

#include <cutils/properties.h>

char value[PROPERTY_VALUE_MAX];

property_get("sys.secpolicy.camera.disabled", value, "0");获取值

四：查看某个人的所以提交 git log --author="xxxx"

五：进入fastboot模式，可以命令adb reboot-bootloader,#*20110606#打开测试开关

六：添加USB,在/etc/udev/rules.d下

七：

Intent.ACTION_USER_PRESENT这个为解锁的广播

KeyguardManager mKeyguardManager = (KeyguardManager) getSystemService(KEYGUARD_SERVICE);



if (mKeyguardManager.inKeyguardRestrictedInputMode()) {

为锁屏状态

}

八：检测耳机是否插入 public boolean checkHeadSet() {

AudioManager audio = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

return audio.isWiredHeadsetOn();

}

Intent.ACTION_HEADSET_PLUG这个为监听耳机的插拔

九：给应用分配最小的内存

VMRuntime.getRuntime()

.setTargetHeapUtilization(TARGET_HEAP_UTILIZATION);

VMRuntime.getRuntime().setMinimumHeapSize(CWJ_HEAP_SIZE);

private final static float TARGET_HEAP_UTILIZATION = 0.75f;

private final static int CWJ_HEAP_SIZE = 6 * 1024 * 1024;

十：monkey测试的命令

adb shell monkey -v -p com.android.XXX --pct-nav 0 --pct-majornav 0 --pct-anyevent 0 --ignore-security-exceptions --throttle 100 -v 50000

十一：不通过数据库直接获取视频第一帧

public static Bitmap createVideoThumbnail(Context context, Uri uri) {

Bitmap bitmap = null;

String className = "android.media.MediaMetadataRetriever";

Object objectMediaMetadataRetriever = null;

Method release = null;

try {

objectMediaMetadataRetriever = Class.forName(className).newInstance();

Method setModeMethod = Class.forName(className).getMethod("setMode", int.class);

setModeMethod.invoke(objectMediaMetadataRetriever,

MediaMetadataRetriever.MODE_CAPTURE_FRAME_ONLY);

Method setDataSourceMethod = Class.forName(className).getMethod(

"setDataSource", Context.class, Uri.class);

setDataSourceMethod.invoke(objectMediaMetadataRetriever, context,uri);

Method captureFrameMethod = Class.forName(className).getMethod("captureFrame");

release = Class.forName(className).getMethod("release");

bitmap = (Bitmap) captureFrameMethod

.invoke(objectMediaMetadataRetriever);

} catch (Exception e) {

e.printStackTrace();

} finally {try {

if (release != null) {

release.invoke(objectMediaMetadataRetriever);

}

} catch (Exception e) {

// Ignore failures while cleaning up.

e.printStackTrace();

}

}

return bitmap;

}

十二：8x25系列camera配置

后摄 500 万 ov5640 ov5647 s5k4e1已经添加

前摄 30万 gc0339 ov9726 ov7692 也已添加

kernel/arch/arm/configs/msm8x25_d8_eg530-perf_defconfig

十三：判断music是否在播放

AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

if(audioManager.isMusicActive())

{

......}

十四：杀死本进程

android.os.Process.killProcess(android.os.Process.myPid());

十五：抓取log

1:带有时间的log: adb logcat -v time >>log.txt

2:把log保存在手机里面，这时候可以在后台运行

adb shell; logcat -vtime >data/log.txt &

十六：选择编译，例如在Android.mk里面，如果msm8x25q_d10_j320c项目，则编译d10_j320c/AndroidManifest.xml这个文件。

ifneq (, $(filter msm8x25q_d10_j320c, $(TARGET_PRODUCT)))

LOCAL_MANIFEST_FILE := d10_j320c/AndroidManifest.xml

endif

十七：外部U盘无法挂载

在DOS中键入, chkdsk F: /f

十八：隐藏输入法

1：隐藏其他应用打开的输入法

InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);

if (imm != null) {

imm.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);



2：隐藏本应用打开的输入法

InputMethodManager inputMethodManager = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);

inputMethodManager.hideSoftInputFromWindow(OpeListActivity.this.getCurrentFocus().getWindowToken(),InputMethodManager.HIDE_NOT_ALWAYS)；

十九：camera的翻转

有两个地方可以改，但是这个要是情况而定，改其中一个

1：在CameraService.cpp中的sendCommand中

if (cmd == CAMERA_CMD_SET_DISPLAY_ORIENTATION) {

// Mirror the preview if the camera is front-facing.

bool isqqpimsecure = false;

if (mCameraFacing == CAMERA_FACING_FRONT) {

int fd;

char buf[1024] = {0};

snprintf(buf,1024,"/proc/%d/cmdline",getCallingPid());

if ((fd = open(buf,O_RDONLY)) != -1) {

if((read(fd, buf, 1023)) != -1) {

ALOGE("sendCommand pid=%d, pname=%s", getCallingPid(), buf);

}

close(fd);

}

if (strcmp(buf, "com.tencent.qqpimsecure") == 0 || strcmp(buf, "com.tencent.mobileqq") == 0 || strcmp(buf, "com.tencent.mobileqq:video") == 0) {

ALOGE("sendCommand pid=%d, pname=%s modifty 180 for com.tencent.qqpimsecure", getCallingPid(), buf);

isqqpimsecure = true;

}

}

orientation = getOrientation(isqqpimsecure ? (arg1 + 180) : arg1, mCameraFacing == CAMERA_FACING_FRONT);

if (orientation == -1) return BAD_VALUE;

if (mOrientation != orientation) {

mOrientation = orientation;

if (mPreviewWindow != 0) {

native_window_set_buffers_transform(mPreviewWindow.get(),

mOrientation);

}

}

return OK;

}

2：在CameraService.cpp中的getCameraInfo修改。

status_t CameraService::getCameraInfo(int cameraId,

struct CameraInfo* cameraInfo) {

if (!mModule) {

return NO_INIT;

}

if (cameraId < 0 || cameraId >= mNumberOfCameras) {

return BAD_VALUE;

}

struct camera_info info;

status_t rc = mModule->get_camera_info(cameraId, &info);

cameraInfo->facing = info.facing;

cameraInfo->orientation = info.orientation;

if (cameraId == CAMERA_FACING_FRONT) {

int fd;

char buf[1024] = {0};

char value2[PROPERTY_VALUE_MAX];

property_get("ro.product.name", value2, "0");

bool isv10_yd=false;

if(strcmp(value2,"msm8x25_v10_w656_yd")==0){

isv10_yd=true;

}

snprintf(buf,1024,"/proc/%d/cmdline",getCallingPid());

if ((fd = open(buf,O_RDONLY)) != -1) {

if((read(fd, buf, 1023)) != -1) {

LOGE("getCameraInfo pid=%d, pname=%s", getCallingPid(), buf);

}

close(fd);

}

if (!isv10_yd && strcmp(buf, "com.tencent.mm") == 0) {

LOGE("getCameraInfo pid=%d, pname=%s modifty 180 for weixin", getCallingPid(), buf);

cameraInfo->orientation += 180;

}else if(strcmp(buf, "com.google.android.talk")==0){

cameraInfo->orientation += 180;

}

}

return rc;

}

二十：当手机没有权限的时候，以下方法可以获取权限，进行install或者push.

#mount

# mount -o remount /dev/block/mtdblock1 /system

# chmod 777 system/app

二十一：CTStest

4.1平台cts命令：单测试某个case: run cts -c class name -m case name 比如：run cts -c android.hardware.cts.CameraGLTest -m testCameraToSurfaceTextureMetadata

测试一个包： run cts -c class name; 比如：run cts -c android.hardware.cts.CameraGLTest

2.3平台cts命令:单测试某个case : start --plan CTS -t class name#case name ,比如,start --plan CTS -t android.hardware.cts.CameraGLTest#testCameraToSurfaceTextureMetadata

测试一个包：start --plan CTS -p class name, 比如： start --plan CTS -p android.hardware.cts.CameraGLTest

二十二：抓起tcpdump信息，tcpdump -i any -p -s 0 -w /sdcard/pcap.pcap

二十三：防止OOM代码

public static int calculateInSampleSize(

BitmapFactory.Options options, int reqWidth, int reqHeight) {

// Raw height and width of image

final int height = options.outHeight;

final int width = options.outWidth;

int inSampleSize = 1;

if (height > reqHeight || width > reqWidth) {

if (width > height) {

inSampleSize = Math.round((float)height / (float)reqHeight);

} else {

inSampleSize = Math.round((float)width / (float)reqWidth);

}

}

return inSampleSize;

}

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,

int reqWidth, int reqHeight) {

// First decode with inJustDecodeBounds=true to check dimensions

final BitmapFactory.Options options = new BitmapFactory.Options();

options.inJustDecodeBounds = true;

BitmapFactory.decodeResource(res, resId, options);

// Calculate inSampleSize

options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

// Decode bitmap with inSampleSize set

options.inJustDecodeBounds = false;

return BitmapFactory.decodeResource(res, resId, options);

}

二十四：查看总内存信息：cat proc/meminfo

二十五：特殊符合表示

＋－×÷

Java中使用+\u2212\u00d7\u00f7表示

二十六：使用命名合patch.

你现在有一个code base： small-src, 你的patch文件放在~/patch/0001-trival-patch.patch

cd small-src

git-am ~/patch/0001-trival-patch.patch

二十七：抓起视频DUMP

1.Dump bit steam and outout yuv data

please run the below command before you test.

adb shell

// dump output yuv

setprop vidc.dec.log.out 1

//dump bit stream

setprop vidc.dec.log.in 1

You shall have the write permission in /data/misc/media

You will find the bitsteam and yuv data on /data/misc/media

2.Enable log.

please run the below command before you test.

a).Enable the omx debug

adb shell setprop vidc.debug.level 7

b.Enable the kernel log

adb shell

su

cd /d/msm_vidc

echo 0x1003 > debug_level

echo 0x3F > fw_level

二十八：命令输入字符串到Edittext里面

adb shell input text asdfsff

二十九：打印数组的内容：

直接打印Arrays.toString(数组名) 即可。