Support disabling the screen blank/lock

device.go

@@ -31,6 +31,11 @@ type Device interface {
 	IsBrowser() bool
 	HasKeyboard() bool
 	SystemScaleForWindow(Window) float32
+
+	// SetDisableScreenBlanking allows an app to ask the device not to sleep/lock/blank displays
+	//
+	// Since: 2.5
+	SetDisableScreenBlanking(bool)
 }
 
 // CurrentDevice returns the device information for the current hardware (via the driver)

internal/driver/glfw/device.go

@@ -23,3 +23,7 @@ func (*glDevice) HasKeyboard() bool {
 func (*glDevice) IsBrowser() bool {
 	return runtime.GOARCH == "js" || runtime.GOOS == "js"
 }
+
+func (*glDevice) SetDisableScreenBlanking(bool) {
+	// TODO implement for Windows, macOS, X11 and Wayland
+}

internal/driver/mobile/android.c

@@ -480,3 +480,25 @@ char* listURI(uintptr_t jni_env, uintptr_t ctx, char* uriCstr) {
 	LOG_FATAL("Unrecognized scheme: %s", uriCstr);
 	return "";
 }
+
+void keepScreenOn(uintptr_t jni_env, uintptr_t ctx, bool disabled) {
+	JNIEnv *env = (JNIEnv*)jni_env;
+	jclass activityClass = find_class(env, "android/app/Activity");
+	jmethodID getWindow = find_method(env, activityClass, "getWindow", "()Landroid/view/Window;");
+
+	jobject win = (*env)->CallObjectMethod(env, (jobject)ctx, getWindow);
+	jclass windowClass = find_class(env, "android/view/Window");
+
+	jmethodID action = NULL;
+	if (disabled) {
+	    action = find_method(env, windowClass, "addFlags", "(I)V");
+	} else {
+	    action = find_method(env, windowClass, "clearFlags", "(I)V");
+	}
+
+    jclass paramsClass = find_class(env, "android/view/WindowManager$LayoutParams" );
+    jfieldID screenFlagField = (*env)->GetStaticFieldID(env, paramsClass, "FLAG_KEEP_SCREEN_ON", "I" );
+    int screenFlag = (*env)->GetStaticIntField(env, paramsClass, screenFlagField);
+
+   	(*env)->CallVoidMethod(env, win, action, screenFlag);
+}

internal/driver/mobile/device.go

@@ -41,6 +41,10 @@ func (*device) HasKeyboard() bool {
 	return false
 }
 
+func (*device) SetDisableScreenBlanking(disable bool) {
+	setDisableScreenBlank(disable)
+}
+
 func (*device) ShowVirtualKeyboard() {
 	showVirtualKeyboard(mobile.DefaultKeyboard)
 }

internal/driver/mobile/device_android.go

@@ -2,7 +2,18 @@
 
 package mobile
 
-import "fyne.io/fyne/v2"
+import (
+	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/driver"
+)
+
+/*
+#include <stdbool.h>
+#include <stdlib.h>
+
+void keepScreenOn(uintptr_t jni_env, uintptr_t ctx, bool disabled);
+*/
+import "C"
 
 const tapYOffset = -12.0 // to compensate for how we hold our fingers on the device
 
@@ -18,3 +29,13 @@ func (*device) SystemScaleForWindow(_ fyne.Window) float32 {
 	}
 	return 1
 }
+
+func setDisableScreenBlank(disable bool) {
+	driver.RunNative(func(ctx any) error {
+		ac := ctx.(*driver.AndroidContext)
+
+		C.keepScreenOn(C.uintptr_t(ac.Env), C.uintptr_t(ac.Ctx), C.bool(disable))
+
+		return nil
+	})
+}

internal/driver/mobile/device_desktop.go

@@ -9,3 +9,7 @@ const tapYOffset = 0 // no finger compensation on desktop (simulation)
 func (*device) SystemScaleForWindow(_ fyne.Window) float32 {
 	return 2 // this is simply due to the high number of pixels on a mobile device - just an approximation
 }
+
+func setDisableScreenBlank(_ bool) {
+	// ignore in mobile simulation mode
+}

internal/driver/mobile/device_ios.go

@@ -4,6 +4,14 @@ package mobile
 
 import "fyne.io/fyne/v2"
 
+/*
+#cgo darwin LDFLAGS: -framework UIKit
+#import <Foundation/Foundation.h>
+
+void disableIdleTimer(BOOL disabled);
+*/
+import "C"
+
 const tapYOffset = -12.0 // to compensate for how we hold our fingers on the device
 
 func (*device) SystemScaleForWindow(_ fyne.Window) float32 {
@@ -14,3 +22,7 @@ func (*device) SystemScaleForWindow(_ fyne.Window) float32 {
 	}
 	return 2
 }
+
+func setDisableScreenBlank(disable bool) {
+	C.disableIdleTimer(C.BOOL(disable))
+}

internal/driver/mobile/device_wayland.go

@@ -9,3 +9,7 @@ const tapYOffset = -4.0 // to compensate for how we hold our fingers on the devi
 func (*device) SystemScaleForWindow(_ fyne.Window) float32 {
 	return 1 // PinePhone simplification, our only wayland mobile currently
 }
+
+func setDisableScreenBlank(_ bool) {
+	// ignore in mobile simulation mode
+}

test/device.go

@@ -31,3 +31,7 @@ func (d *device) SystemScaleForWindow(fyne.Window) float32 {
 func (*device) IsBrowser() bool {
 	return runtime.GOARCH == "js" || runtime.GOOS == "js"
 }
+
+func (*device) SetDisableScreenBlanking(_ bool) {
+	// no-op for test
+}