From 412a7c5db639399b1bbaa4516d56f390884ea28b Mon Sep 17 00:00:00 2001
From: Rachel Blackman <[EMAIL REDACTED]>
Date: Mon, 27 Jul 2026 15:43:23 -0700
Subject: [PATCH] Use the modern OnBackInvokedCallback method to trap the back
button on newer Android devices (#16052)
---
.../app/src/main/AndroidManifest.xml | 2 +-
.../main/java/org/libsdl/app/SDLActivity.java | 44 +++++++++++++++++++
src/core/android/SDL_android.c | 15 ++++++-
src/core/android/SDL_android.h | 1 +
src/video/android/SDL_androidvideo.c | 14 ++++++
5 files changed, 74 insertions(+), 2 deletions(-)
diff --git a/android-project/app/src/main/AndroidManifest.xml b/android-project/app/src/main/AndroidManifest.xml
index 1111a223dcf28..93e851286646a 100644
--- a/android-project/app/src/main/AndroidManifest.xml
+++ b/android-project/app/src/main/AndroidManifest.xml
@@ -71,7 +71,7 @@
android:icon="@mipmap/ic_launcher"
android:allowBackup="true"
android:theme="@style/AppTheme"
- android:enableOnBackInvokedCallback="false"
+ android:enableOnBackInvokedCallback="true"
android:hardwareAccelerated="true" >
<!-- Example of setting SDL hints from AndroidManifest.xml:
diff --git a/android-project/app/src/main/java/org/libsdl/app/SDLActivity.java b/android-project/app/src/main/java/org/libsdl/app/SDLActivity.java
index ed1ffd509143a..b495e8773dda6 100644
--- a/android-project/app/src/main/java/org/libsdl/app/SDLActivity.java
+++ b/android-project/app/src/main/java/org/libsdl/app/SDLActivity.java
@@ -24,6 +24,7 @@
import android.os.Bundle;
import android.os.Handler;
import android.os.LocaleList;
+import android.os.Looper;
import android.os.Message;
import android.os.ParcelFileDescriptor;
import android.provider.DocumentsContract;
@@ -50,6 +51,8 @@
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
+import android.window.OnBackInvokedCallback;
+import android.window.OnBackInvokedDispatcher;
import java.io.FileNotFoundException;
import java.util.ArrayList;
@@ -784,6 +787,47 @@ public void onBackPressed() {
}
}
+ static OnBackInvokedCallback backButtonCallback = new OnBackInvokedCallback() {
+ Handler mBackKeyHandler;
+
+ @Override
+ public void onBackInvoked() {
+ if (mBackKeyHandler == null) {
+ mBackKeyHandler = new Handler(Looper.getMainLooper());
+ }
+
+ onNativeKeyDown(KeyEvent.KEYCODE_BACK);
+ mBackKeyHandler.postDelayed(new Runnable() {
+ @Override
+ public void run() {
+ onNativeKeyUp(KeyEvent.KEYCODE_BACK);
+ }
+ }, 500);
+ }
+ };
+
+ static boolean mBackKeyTrapEnabled = false;
+ public static void setBackButtonTrapEnabled(boolean enabled) {
+
+ if ( Build.VERSION.SDK_INT < 33 ) {
+ // We're old enough that we just use the old onBackPressed behavior.
+ return;
+ }
+
+ // Check so we don't register the same callback twice.
+ if (enabled == mBackKeyTrapEnabled) {
+ return;
+ }
+
+ if (enabled) {
+ mSingleton.getOnBackInvokedDispatcher().registerOnBackInvokedCallback(OnBackInvokedDispatcher.PRIORITY_DEFAULT, backButtonCallback);
+ }
+ else {
+ mSingleton.getOnBackInvokedDispatcher().unregisterOnBackInvokedCallback(backButtonCallback);
+ }
+ mBackKeyTrapEnabled = enabled;
+ }
+
// File dialog types
private static final int SDL_FILEDIALOG_OPENFILE = 0;
private static final int SDL_FILEDIALOG_SAVEFILE = 1;
diff --git a/src/core/android/SDL_android.c b/src/core/android/SDL_android.c
index eedb4af4dfff6..de4d39120f538 100644
--- a/src/core/android/SDL_android.c
+++ b/src/core/android/SDL_android.c
@@ -101,6 +101,7 @@ static jmethodID midManualBackButton;
static jmethodID midShowFileDialog;
#endif // !SDL_DIALOG_DISABLED
static jmethodID midGetPreferredLocales;
+static jmethodID midSetBackButtonTrapEnabled;
#ifndef SDL_VIDEO_DISABLED
// Video/surface method signatures
@@ -681,6 +682,7 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
midShowFileDialog = (*env)->GetStaticMethodID(env, mActivityClass, "showFileDialog", "([Ljava/lang/String;ZILjava/lang/String;I)Z");
#endif // !SDL_DIALOG_DISABLED
midGetPreferredLocales = (*env)->GetStaticMethodID(env, mActivityClass, "getPreferredLocales", "()Ljava/lang/String;");
+ midSetBackButtonTrapEnabled = (*env)->GetStaticMethodID(env, mActivityClass, "setBackButtonTrapEnabled", "(Z)V");
if (!midGetContext ||
!midGetDeviceFormFactor ||
@@ -698,7 +700,8 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
#ifndef SDL_DIALOG_DISABLED
!midShowFileDialog ||
#endif
- !midGetPreferredLocales) {
+ !midGetPreferredLocales ||
+ !midSetBackButtonTrapEnabled) {
__android_log_print(ANDROID_LOG_WARN, "SDL", "Missing some core Java callbacks, do you have the latest version of SDLActivity.java?");
}
@@ -3714,4 +3717,14 @@ bool Android_JNI_ShowFileDialog(
}
#endif // !SDL_DIALOG_DISABLED
+void Android_JNI_SetBackButtonTrapActive(bool enabled)
+{
+ if (!midSetBackButtonTrapEnabled) {
+ return;
+ }
+
+ JNIEnv *env = Android_JNI_GetEnv();
+ (*env)->CallStaticVoidMethod(env, mActivityClass, midSetBackButtonTrapEnabled, enabled);
+}
+
#endif // SDL_PLATFORM_ANDROID
diff --git a/src/core/android/SDL_android.h b/src/core/android/SDL_android.h
index b6c6a31438f4b..01074612e9c65 100644
--- a/src/core/android/SDL_android.h
+++ b/src/core/android/SDL_android.h
@@ -60,6 +60,7 @@ void Android_LockActivityMutex(void);
void Android_UnlockActivityMutex(void);
void Android_SetAllowRecreateActivity(bool enabled);
+void Android_JNI_SetBackButtonTrapActive(bool enabled);
#ifndef SDL_VIDEO_DISABLED
#include <EGL/eglplatform.h>
diff --git a/src/video/android/SDL_androidvideo.c b/src/video/android/SDL_androidvideo.c
index d868e6960e264..2157d1168e013 100644
--- a/src/video/android/SDL_androidvideo.c
+++ b/src/video/android/SDL_androidvideo.c
@@ -28,6 +28,7 @@
#include "../SDL_pixels_c.h"
#include "../../events/SDL_events_c.h"
#include "../../events/SDL_windowevents_c.h"
+#include "../../SDL_hints_c.h"
#include "SDL_androidvideo.h"
#include "SDL_androidgl.h"
@@ -81,6 +82,16 @@ static void Android_DeleteDevice(SDL_VideoDevice *device)
SDL_free(device);
}
+// Input is part of video for Android, so this goes here.
+static void SDLCALL Android_Video_InternalHintCallback(
+ void *userdata,
+ const char *name,
+ const char *oldvalue,
+ const char *newvalue)
+{
+ Android_JNI_SetBackButtonTrapActive(SDL_GetStringBoolean(newvalue, false));
+}
+
static SDL_VideoDevice *Android_CreateDevice(void)
{
SDL_VideoDevice *device;
@@ -185,6 +196,8 @@ bool Android_VideoInit(SDL_VideoDevice *_this)
display->current_orientation = Android_JNI_GetDisplayCurrentOrientation();
display->content_scale = Android_ScreenDensity;
+ SDL_AddHintCallback(SDL_HINT_ANDROID_TRAP_BACK_BUTTON, Android_Video_InternalHintCallback, 0);
+
Android_InitTouch();
Android_InitMouse();
@@ -195,6 +208,7 @@ bool Android_VideoInit(SDL_VideoDevice *_this)
void Android_VideoQuit(SDL_VideoDevice *_this)
{
+ SDL_RemoveHintCallback(SDL_HINT_ANDROID_TRAP_BACK_BUTTON, Android_Video_InternalHintCallback, 0);
Android_QuitMouse();
Android_QuitTouch();
}