Lineageos 22.1(Android 15)更换开机动画

一、原理简介

我们直接用最简单的替换zip的方式来更换开机动画，首先我们要查看系统代码使用的zip包的路径，可能与aosp原生的代码不一定一样。
/frameworks/base/cmds/bootanimation/BootAnimation.cpp

bool BootAnimation::threadLoop() {ATRACE_CALL();bool result;initShaders();// We have no bootanimation file, so we use the stock android logo// animation.if (mZipFileName.empty()) {ALOGD("No animation file");result = android();} else {result = movie();}//**省略后续代码**//
}

看到是使用mZipFileName来判断的，我们看看初始化的地方

bool BootAnimation::findBootAnimationFileInternal(const std::vector<std::string> &files) {ATRACE_CALL();for (const std::string& f : files) {if (access(f.c_str(), R_OK) == 0) {mZipFileName = f.c_str();return true;}}return false;
}void BootAnimation::findBootAnimationFile() {ATRACE_CALL();const bool playDarkAnim = android::base::GetIntProperty("ro.boot.theme", 0) == 1;const std::string productBootanimationFile = PRODUCT_BOOTANIMATION_DIR +android::base::GetProperty("ro.product.bootanim.file", playDarkAnim ?PRODUCT_BOOTANIMATION_DARK_FILE : PRODUCT_BOOTANIMATION_FILE);static const std::vector<std::string> bootFiles = {APEX_BOOTANIMATION_FILE, productBootanimationFile,OEM_BOOTANIMATION_FILE, SYSTEM_BOOTANIMATION_FILE};static const std::vector<std::string> shutdownFiles = {PRODUCT_SHUTDOWNANIMATION_FILE, OEM_SHUTDOWNANIMATION_FILE, SYSTEM_SHUTDOWNANIMATION_FILE, ""};static const std::vector<std::string> userspaceRebootFiles = {PRODUCT_USERSPACE_REBOOT_ANIMATION_FILE, OEM_USERSPACE_REBOOT_ANIMATION_FILE,SYSTEM_USERSPACE_REBOOT_ANIMATION_FILE,};if (android::base::GetBoolProperty("sys.init.userspace_reboot.in_progress", false)) {findBootAnimationFileInternal(userspaceRebootFiles);} else if (mShuttingDown) {findBootAnimationFileInternal(shutdownFiles);} else {//查找开机动画的路径findBootAnimationFileInternal(bootFiles);}
}

通过代码我们可以查找到几个路径，最好验证的方式直接adb shell然后查找几个zip是否存在，也可以看Bootanimation的日志。最后我们发现是在/product/media/下面的动画zip文件。到这里如果有现成的zip可以push直接替换验证，要编译的时候起作用我们还需要看看这个zpi的生成规则。

规则mk的路径
/media/arcxea/stat/lineageos/vendor/lineage/bootanimation/Android.mk

#
# Copyright (C) 2016 The CyanogenMod Project
#               2017-2024 The LineageOS Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#TARGET_GENERATED_BOOTANIMATION := $(TARGET_OUT_INTERMEDIATES)/BOOTANIMATION/bootanimation.zip
$(TARGET_GENERATED_BOOTANIMATION): INTERMEDIATES := $(call intermediates-dir-for,BOOTANIMATION,bootanimation)
$(TARGET_GENERATED_BOOTANIMATION): $(SOONG_ZIP)@echo "Building bootanimation.zip"@rm -rf $(dir $@)@mkdir -p $(INTERMEDIATES)$(hide) tar xfp vendor/lineage/bootanimation/bootanimation.tar -C $(INTERMEDIATES)$(hide) if [ $(TARGET_SCREEN_HEIGHT) -lt $(TARGET_SCREEN_WIDTH) ]; then \IMAGEWIDTH=$(TARGET_SCREEN_HEIGHT); \else \IMAGEWIDTH=$(TARGET_SCREEN_WIDTH); \fi; \IMAGESCALEWIDTH=$$IMAGEWIDTH; \IMAGESCALEHEIGHT=$$(expr $$IMAGESCALEWIDTH / 3); \if [ "$(TARGET_BOOTANIMATION_HALF_RES)" = "true" ]; then \IMAGEWIDTH="$$(expr "$$IMAGEWIDTH" / 2)"; \fi; \IMAGEHEIGHT=$$(expr $$IMAGEWIDTH / 3); \RESOLUTION="$$IMAGEWIDTH"x"$$IMAGEHEIGHT"; \prebuilts/tools-lineage/${HOST_OS}-x86/bin/mogrify -resize $$RESOLUTION -colors 256 $(INTERMEDIATES)/*/*.png; \echo "$$IMAGESCALEWIDTH $$IMAGESCALEHEIGHT 60" > $(INTERMEDIATES)/desc.txt; \cat vendor/lineage/bootanimation/desc.txt >> $(INTERMEDIATES)/desc.txt$(hide) $(SOONG_ZIP) -L 0 -o $@ -C $(INTERMEDIATES) -D $(INTERMEDIATES)ifeq ($(TARGET_BOOTANIMATION),)TARGET_BOOTANIMATION := $(TARGET_GENERATED_BOOTANIMATION)
endifinclude $(CLEAR_VARS)
LOCAL_MODULE := bootanimation.zip
LOCAL_MODULE_CLASS := ETC
LOCAL_MODULE_PATH := $(TARGET_OUT_PRODUCT)/mediainclude $(BUILD_SYSTEM)/base_rules.mk$(LOCAL_BUILT_MODULE): $(TARGET_BOOTANIMATION)@cp $(TARGET_BOOTANIMATION) $@include $(CLEAR_VARS)BOOTANIMATION_SYMLINK := $(TARGET_OUT_PRODUCT)/media/bootanimation-dark.zip
$(BOOTANIMATION_SYMLINK): $(LOCAL_INSTALLED_MODULE)@mkdir -p $(dir $@)$(hide) ln -sf bootanimation.zip $@ALL_DEFAULT_INSTALLED_MODULES += $(BOOTANIMATION_SYMLINK)

大概看了一下就明白了，图片放在bootanimation.tar，解压并做了分辨率适配，然后和desc.txt一起打包，看了下desc.txt只支持3个part，我们可以按照开始，循环，结束三个part1,part2,part3来放入图片即可，更换掉原本的bootanimation.tar。

二、编译

替换完成后我们执行编译命令

make bootanimation.zip

这时候我们可以找到生成的动画zip，在这个路径下面ineageos/out/target/product/blueline/obj/BOOTANIMATION/，这时候我们整编就起作用了。简单验证的话push到/product/media/路径开机就行，总体还是比较简单的。