XPosed是與Cydia其名的工具，它能夠讓Android設備在沒有修改源碼的情況下修改系統中的API運行結果。我們通常稱之為：God Mode（上帝模式）。

之前享大家分享了Xposed的基礎，Xposed的作用和最簡單的用法。那么，它的原理和它的內部構造是如何構成的？下面，我們從Github上看看，rovo89大神是如何制作的。

rovo89的github地址：https://github.com/rovo89

在主頁上我們看到了，xposed其實主要是由三個項目來組成的，如下圖所示；?

三個分別是：

項目 說明

Xposed	Xposed框架的native部分（主要是改性app_process二進制文件）
XposedInstaller	Xposed框架的Android端本地管理，環境架構搭建，以及第三方module資源下載的工具。
XposedBridge	Xposed向開發者提供的API與相應的工具類庫

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XposedInstaller的構成

Xposed項目使我們最常用的項目，當然，他也是構造Xposed的核心部分。（也許你會說，其實是xposed項目更重要，它主要是替換app_process，ok我們后面再說它）。

如下圖所示，是我們在XPosedInstaller apk中見到的，安裝xposed框架的界面。?

InstallerFragment我們能夠在其中找到install方法，其中主要就是針對使用不同方式的將自定義的app_process文件替換掉系統的app_process文件。

<code class="hljs cs has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"> <span class="hljs-comment" style="color:#8800;box-sizing: border-box;">/*** xposed install* @return 安裝成功返回true，否則false*/</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">private</span> boolean <span class="hljs-title" style="box-sizing: border-box;">install</span>() {<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 獲取安裝的方式，直接寫入 or 使用 recovery進行安裝</span>final <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">int</span> installMode = getInstallMode();<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 檢查獲取Root權限</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (!startShell())<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;List<String> messages = <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">new</span> LinkedList<String>();boolean showAlert = <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">true</span>;<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">try</span> {messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.sdcard_location, XposedApp.getInstance().getExternalFilesDir(<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">null</span>)));messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_copying, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Disabler-Recovery.zip"</span>));<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 把Xposed-Disabler-Recovery.zip文件 從asset copy到sdcard中</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (AssetUtil.writeAssetToSdcardFile(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Disabler-Recovery.zip"</span>, <span class="hljs-number" style="color:#06666;box-sizing: border-box;">00644</span>) == <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">null</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_extract_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Disabler-Recovery.zip"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 將編譯后的app_process二進制文件，從asset文件夾中，copy到/data/data/de.robv.android.xposed.installer/bin/app_process下</span>File appProcessFile = AssetUtil.writeAssetToFile(APP_PROCESS_NAME, <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">new</span> File(XposedApp.BASE_DIR + <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"bin/app_process"</span>), <span class="hljs-number" style="color:#06666;box-sizing: border-box;">00700</span>);<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (appProcessFile == <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">null</span>) {showAlert(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_extract_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"app_process"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (installMode == INSTALL_MODE_NORMAL) {<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 普通安裝模式</span><span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 重新掛載/system為rw模式</span>messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_mounting_writable, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"mount -o remount,rw /system"</span>, messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_mount_writable_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system"</span>));messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_trying_to_continue));}<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 查看原有的app_process文件是否已經備份，如果沒有備份，現將原有的app_process文件備份一下</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">new</span> File(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process.orig"</span>).exists()) {messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_backup_already_exists, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process.orig"</span>));} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">else</span> {<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"cp -a /system/bin/app_process /system/bin/app_process.orig"</span>, messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_backup_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">else</span> {messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_backup_successful, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process.orig"</span>));}mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"sync"</span>, messages);}<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 將項目中的自定義app_process文件copy覆蓋系統的app_process,修改權限</span>messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_copying, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"app_process"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"cp -a "</span> + appProcessFile.getAbsolutePath() + <span class="hljs-string" style="color:#0880;box-sizing: border-box;">" /system/bin/app_process"</span>, messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_copy_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"app_process"</span>, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"chmod 755 /system/bin/app_process"</span>, messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_set_perms_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"chown root:shell /system/bin/app_process"</span>, messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_set_owner_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"/system/bin/app_process"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">else</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (installMode == INSTALL_MODE_RECOVERY_AUTO) {<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 自動進入Recovery</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (!prepareAutoFlash(messages, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Installer-Recovery.zip"</span>))<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">else</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (installMode == INSTALL_MODE_RECOVERY_MANUAL) {<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 手動進入Recovery</span><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (!prepareManualFlash(messages, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Installer-Recovery.zip"</span>))<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}File blocker = <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">new</span> File(XposedApp.BASE_DIR + <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"conf/disabled"</span>);<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (blocker.exists()) {messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_removing, blocker.getAbsolutePath()));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"rm "</span> + blocker.getAbsolutePath(), messages) != <span class="hljs-number" style="color:#06666;box-sizing: border-box;">0</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_remove_failed, blocker.getAbsolutePath()));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}}<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// copy XposedBridge.jar 到私有目錄 XposedBridge.jar是Xposed提供的jar文件，負責在Native層與FrameWork層進行交互</span>messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_copying, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"XposedBridge.jar"</span>));File jarFile = AssetUtil.writeAssetToFile(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"XposedBridge.jar"</span>, <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">new</span> File(JAR_PATH_NEWVERSION), <span class="hljs-number" style="color:#06666;box-sizing: border-box;">00644</span>);<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (jarFile == <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">null</span>) {messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);messages.add(getString(R.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">string</span>.file_extract_failed, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"XposedBridge.jar"</span>));<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;}mRootUtil.executeWithBusybox(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"sync"</span>, messages);showAlert = <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">false</span>;messages.add(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">""</span>);<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (installMode == INSTALL_MODE_NORMAL) {offerReboot(messages);} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">else</span> {offerRebootToRecovery(messages, <span class="hljs-string" style="color:#0880;box-sizing: border-box;">"Xposed-Installer-Recovery.zip"</span>, installMode);}<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">true</span>;} <span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">finally</span> {<span class="hljs-comment" style="color:#8800;box-sizing: border-box;">// 刪除busybox 工具庫</span>AssetUtil.removeBusybox();<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">if</span> (showAlert)showAlert(TextUtils.<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">join</span>(<span class="hljs-string" style="color:#0880;box-sizing: border-box;">"\n"</span>, messages).trim());}}</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: 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5px;">76</li><li style="box-sizing: border-box; padding: 0px 5px;">77</li><li style="box-sizing: border-box; padding: 0px 5px;">78</li><li style="box-sizing: border-box; padding: 0px 5px;">79</li><li style="box-sizing: border-box; padding: 0px 5px;">80</li><li style="box-sizing: border-box; padding: 0px 5px;">81</li><li style="box-sizing: border-box; padding: 0px 5px;">82</li><li style="box-sizing: border-box; padding: 0px 5px;">83</li><li style="box-sizing: border-box; padding: 0px 5px;">84</li><li style="box-sizing: border-box; padding: 0px 5px;">85</li><li style="box-sizing: border-box; padding: 0px 5px;">86</li><li style="box-sizing: border-box; padding: 0px 5px;">87</li><li style="box-sizing: border-box; padding: 0px 5px;">88</li><li style="box-sizing: border-box; padding: 0px 5px;">89</li><li style="box-sizing: border-box; padding: 0px 5px;">90</li><li style="box-sizing: border-box; padding: 0px 5px;">91</li><li style="box-sizing: border-box; padding: 0px 5px;">92</li><li style="box-sizing: border-box; padding: 0px 5px;">93</li><li style="box-sizing: border-box; padding: 0px 5px;">94</li><li style="box-sizing: border-box; padding: 0px 5px;">95</li><li style="box-sizing: border-box; padding: 0px 5px;">96</li><li style="box-sizing: border-box; padding: 0px 5px;">97</li><li style="box-sizing: border-box; padding: 0px 5px;">98</li><li style="box-sizing: border-box; padding: 0px 5px;">99</li><li style="box-sizing: border-box; padding: 0px 5px;">100</li><li style="box-sizing: border-box; padding: 0px 5px;">101</li><li style="box-sizing: border-box; padding: 0px 5px;">102</li><li style="box-sizing: border-box; padding: 0px 5px;">103</li><li style="box-sizing: border-box; padding: 0px 5px;">104</li><li style="box-sizing: border-box; padding: 0px 5px;">105</li><li style="box-sizing: border-box; padding: 0px 5px;">106</li><li style="box-sizing: border-box; padding: 0px 5px;">107</li><li style="box-sizing: border-box; padding: 0px 5px;">108</li><li style="box-sizing: border-box; padding: 0px 5px;">109</li><li style="box-sizing: border-box; padding: 0px 5px;">110</li><li style="box-sizing: border-box; padding: 0px 5px;">111</li><li style="box-sizing: border-box; padding: 0px 5px;">112</li><li style="box-sizing: border-box; padding: 0px 5px;">113</li><li style="box-sizing: border-box; padding: 0px 5px;">114</li><li style="box-sizing: border-box; padding: 0px 5px;">115</li><li style="box-sizing: border-box; padding: 0px 5px;">116</li><li style="box-sizing: border-box; padding: 0px 5px;">117</li><li style="box-sizing: border-box; padding: 0px 5px;">118</li><li style="box-sizing: border-box; padding: 0px 5px;">119</li><li style="box-sizing: border-box; padding: 0px 5px;">120</li><li style="box-sizing: border-box; padding: 0px 5px;">121</li><li style="box-sizing: border-box; padding: 0px 5px;">122</li><li style="box-sizing: border-box; padding: 0px 5px;">123</li><li style="box-sizing: border-box; padding: 0px 5px;">124</li><li style="box-sizing: border-box; padding: 0px 5px;">125</li><li style="box-sizing: border-box; padding: 0px 5px;">126</li></ul>

ok，我們看完了代碼，發現所有的工作都是為了app_process文件的替換。那么，系統中這個app_process是做什么的？為什么我們需要替換？替換成什么樣？替換后對于我們么來說有什么幫助呢？

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Xposed原理

我們在android的源碼中的init.rc文件可以看到

<code class="hljs livecodeserver has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;">service zygote /<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">system</span>/bin/app_process -Xzygote /<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">system</span>/bin –zygote –start-<span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">system</span>-server <span class="hljs-built_in" style="color:#66066;box-sizing: border-box;">socket</span> zygote stream <span class="hljs-number" style="color:#06666;box-sizing: border-box;">666</span> onrestart <span class="hljs-built_in" style="color:#66066;box-sizing: border-box;">write</span> /sys/android_power/request_state wake onrestart <span class="hljs-built_in" style="color:#66066;box-sizing: border-box;">write</span> /sys/power/state <span class="hljs-command" style="box-sizing: border-box;"><span class="hljs-keyword" style="color:#0088;box-sizing: border-box;">on</span></span> onrestart restart media onrestart restart netd</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li></ul>

app_process是andriod app的啟動程序（具體形式是zygote fork()調用一個 app_process作為Android app的載體）

Xposed的實現方案

針對Hook的不同進程來說又可以分為全局Hook與單個應用程序進程Hook，我們知道在Android系統中，應用程序進程都是由Zygote進程孵化出來的，而Zygote進程是由Init進程啟動的。

Zygote進程在啟動時會創建一個Dalvik虛擬機實例，每當它孵化一個新的應用程序進程時，都會將這個Dalvik虛擬機實例復制到新的應用程序進程里面去，從而使得每一個應用程序進程都有一個獨立的Dalvik虛擬機實例。所以如果選擇對Zygote進程Hook，則能夠達到針對系統上所有的應用程序進程Hook，即一個全局Hook。如下圖所示：

原文地址： http://blog.csdn.net/yzzst/article/details/47659987

總結

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