SMALI 帮助 - 从资源中获取字符串

编程问答 2022-05-15

问题描述

我用 APKTool 反编译了一个 apk，在一个 .smali 文件中我得到了这个代码：

.class public Lc/c/a/a;
.super Ljava/lang/Object;
.source "SourceFile"

# instance fields
.field public a:Ljava/lang/String;

# direct methods
.method public constructor <init>()V
    .locals 1

    .line 1
    invoke-direct {p0},Ljava/lang/Object;-><init>()V

    const-string v0,"Choose Storage"

    .line 2
    iput-object v0,p0,Lc/c/a/a;->a:Ljava/lang/String;

    return-void
.end method

我的问题是我需要从资源文件中获取“const-string,v0”。 我尝试添加到字段中，增加本地人

.field public l:Landroid/content/Context;

然后在“const-string v0”之后添加下一个代码：

const v1,0x7f1200a3

iget-object v0,Lc/c/a/a;->l:Landroid/content/Context;

invoke-virtual {v0,v1},Landroid/content/Context;->getString(I)Ljava/lang/String;

move-result-object v0

但是此时打开应用程序会崩溃。

完整的修改代码

.class public Lc/c/a/a;
.super Ljava/lang/Object;
.source "SourceFile"

# instance fields
.field public a:Ljava/lang/String;

.field public l:Landroid/content/Context;

# direct methods
.method public constructor <init>()V
    .locals 2

    .line 1
    invoke-direct {p0},"Choose Storage"

    const v1,0x7f1200a3

    iget-object v0,Lc/c/a/a;->l:Landroid/content/Context;

    invoke-virtual {v0,Landroid/content/Context;->getString(I)Ljava/lang/String;

    move-result-object v0

    .line 2
    iput-object v0,Lc/c/a/a;->a:Ljava/lang/String;

    return-void
.end method

LOGCAT 错误

java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String andoid.content.Contect.getString(int)' on a null object reference

解决方法

因为 l 没有值，请尝试使用上下文构造。

.class public Lc/c/a/a;
.super Ljava/lang/Object;
.source "SourceFile"

# instance fields
.field public a:Ljava/lang/String;

.field public l:Landroid/content/Context;

# direct methods
.method public constructor <init>(Landroid/content/Context;)V
    .locals 3

    invoke-direct {p0},Ljava/lang/Object;-><init>()V
    
    #Assign value to l
    iput-object p1,p0,Lc/c/a/a;->l:Landroid/content/Context;
    
    const v0,0x7f1200a3

    invoke-virtual {p1,v0},Landroid/content/Context;->getString(I)Ljava/lang/String;

    move-result-object v0

    iput-object v0,Lc/c/a/a;->a:Ljava/lang/String;

    return-void
.end method

就这样 compiled

androidandroidresourcessmalismalistringstring