Android应用按功能分包后启动崩溃问题排查与修复求助

问题背景 #

开发一款需要权限授权的Android应用，所有Java类放在根包com.example.permission时运行正常。为整合项目按功能分包（仅MainActivity.java留在根包），修改了包名和变量可见性但未改动业务逻辑，应用启动后立即崩溃。

崩溃报错信息 #

FATAL EXCEPTION: main
Process: com.example.permission, PID: 3291
java.lang.RuntimeException: Unable to resume activity {com.example.permission/com.example.permission.MainActivity}: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
    at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4962)
    at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:4995)
    at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:229)
    at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:205)
    at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:177)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:98)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2443)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loopOnce(Looper.java:205)
    at android.os.Looper.loop(Looper.java:294)
    at android.app.ActivityThread.main(ActivityThread.java:8177)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:552)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:971)
Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
    at com.example.permission.permission.OnPermissionsResult.onPermissionsResult(OnPermissionsResult.java:49)
    at com.example.permission.MainActivity.onRequestPermissionsResult(MainActivity.java:104)
    at android.app.Activity.requestPermissions(Activity.java:5479)
    at androidx.core.app.ActivityCompat$Api23Impl.requestPermissions(ActivityCompat.java:904)
    at androidx.core.app.ActivityCompat.requestPermissions(ActivityCompat.java:545)
    at com.example.permission.permission.CheckPermission.askPermissionBox(CheckPermission.java:171)
    at com.example.permission.MainActivity.onResume(MainActivity.java:125)
    at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1603)
    at android.app.Activity.performResume(Activity.java:8743)
    at android.app.ActivityThread.performResumeActivity(ActivityThread.java:4952)
    ...

问题根源 #

报错指向OnPermissionsResult.java第49行的数组越界：代码直接访问mypermissions[0]但未判断数组是否为空、长度是否大于0。

分包操作本身不影响业务逻辑，但该代码存在潜在bug：当权限请求的permissions数组为空时（比如权限参数传递异常、系统返回空数组等场景），未做判空处理就直接访问索引0，触发崩溃。之前同包运行时未触发该场景，分包后因环境或调用路径变化导致bug暴露。

修复方案 #

在访问mypermissions数组的索引前，先增加非空和长度校验：

1. 在OnPermissionsResult的onPermissionsResult()方法中，对mypermissions数组增加校验逻辑
2. 若数组为空，直接跳过对应分支处理，避免崩溃
3. 同时在后续调用askPermissionBox时，也校验数组非空，从源头避免空数组进入流程

修改后的代码示例 #

调整OnPermissionsResult.java中的onPermissionsResult()方法：

public void onPermissionsResult() {
    for (int permission : mygrandResults) {
        permissionChecker = permissionChecker + permission;
    }

    if (permissionChecker == PackageManager.PERMISSION_GRANTED && mygrandResults.length > 0) {
        OnPermissionGranted onPermissionGranted =
            new OnPermissionGranted(myrequestCode, mycontext, myactivity);
        onPermissionGranted.skip_to_next_permission(myrequestCode, myactivity);
    } 
    // 增加mypermissions非空且长度大于0的判断
    else if (mypermissions != null && mypermissions.length > 0 
             && !ActivityCompat.shouldShowRequestPermissionRationale(myactivity, mypermissions[0])) {
        AlertDialog.Builder builder = new AlertDialog.Builder(myactivity);
        builder.setMessage("This feature is unavailable as this feature requires permission that you have denied. Please allow " + mypermissions[0] + " from settings to proceed further.")
            .setTitle("Permission Required")
            .setCancelable(false)
            .setNegativeButton("Cancel", (dialog, which) -> {
                dialog.dismiss();
            })
            .setPositiveButton("Settings", (dialog, which) -> {
                try {
                    dialog.dismiss();
                    Intent intent = new Intent();
                    intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                    Uri uri = Uri.fromParts("package",
                            myactivity.getPackageName(), null);
                    intent.setData(uri);
                    myactivity.startActivity(intent);
                } catch (Exception e) {
                    dialog.dismiss();
                    Intent intent = new Intent();
                    intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                    myactivity.startActivity(intent);
                }
            });
        builder.show();
    } else {
        // 校验mypermissions非空，避免传递空数组
        if (mypermissions != null) {
            CheckPermission checkPermission =
                    new CheckPermission(mycontext, myactivity);
            checkPermission.askPermissionBox(mypermissions, myrequestCode);
        }
    }
}

额外建议：检查CheckPermission类的askPermissionBox方法，确保接收的权限数组不为空，从源头规避空数组进入权限请求流程。

内容的提问来源于stack exchange，提问作者Lo Dennis