app, app/internal: [wasm,android] new Option to change navigation/status color

Signed-off-by: Inkeliz <inkeliz@inkeliz.com>

app/internal/wm/GioView.java

@@ -29,6 +29,8 @@ import android.view.WindowInsets;
 import android.view.Surface;
 import android.view.SurfaceView;
 import android.view.SurfaceHolder;
+import android.view.Window;
+import android.view.WindowInsetsController;
 import android.view.inputmethod.BaseInputConnection;
 import android.view.inputmethod.InputConnection;
 import android.view.inputmethod.InputMethodManager;
@@ -132,6 +134,70 @@ public final class GioView extends SurfaceView implements Choreographer.FrameCal
 		setPointerIcon(pointerIcon);
 	}
 
+    private enum Bar {
+        NAVIGATION,
+        STATUS,
+    }
+
+    private void setBarColor(Bar t, int color, int luminance) {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+            return;
+        }
+
+        Window window = ((Activity) this.getContext()).getWindow();
+
+        int insetsMask;
+        int viewMask;
+
+        switch (t) {
+        case STATUS:
+            insetsMask = WindowInsetsController.APPEARANCE_LIGHT_STATUS_BARS;
+            viewMask = View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR;
+            window.setStatusBarColor(color);
+            break;
+        case NAVIGATION:
+            insetsMask = WindowInsetsController.APPEARANCE_LIGHT_NAVIGATION_BARS;
+            viewMask = View.SYSTEM_UI_FLAG_LIGHT_NAVIGATION_BAR;
+            window.setNavigationBarColor(color);
+            break;
+        default:
+            throw new RuntimeException("invalid bar type");
+        }
+
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
+            return;
+        }
+
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.R) {
+            int flags = this.getSystemUiVisibility();
+            if (luminance > 128) {
+               flags |=  viewMask;
+            } else {
+               flags &= ~viewMask;
+            }
+            this.setSystemUiVisibility(flags);
+            return;
+        }
+
+        WindowInsetsController insetsController = window.getInsetsController();
+        if (insetsController == null) {
+            return;
+        }
+        if (luminance > 128) {
+            insetsController.setSystemBarsAppearance(insetsMask, insetsMask);
+        } else {
+            insetsController.setSystemBarsAppearance(0, insetsMask);
+        }
+    }
+
+    private void setStatusColor(int color, int luminance) {
+        this.setBarColor(Bar.STATUS, color, luminance);
+    }
+
+    private void setNavigationColor(int color, int luminance) {
+        this.setBarColor(Bar.NAVIGATION, color, luminance);
+    }
+
 	private void dispatchMotionEvent(MotionEvent event) {
 		for (int j = 0; j < event.getHistorySize(); j++) {
 			long time = event.getHistoricalEventTime(j);

app/internal/wm/os_android.go

@@ -42,7 +42,9 @@ import "C"
 import (
 	"errors"
 	"fmt"
+	"gioui.org/internal/f32color"
 	"image"
+	"image/color"
 	"reflect"
 	"runtime"
 	"runtime/debug"
@@ -83,6 +85,8 @@ type window struct {
 // re-creates our Activity.
 type windowState struct {
 	cursor          *pointer.CursorName
+	navigationColor *color.NRGBA
+	statusColor     *color.NRGBA
 }
 
 // gioView hold cached JNI methods for GioView.
@@ -94,6 +98,8 @@ var gioView struct {
 	hideTextInput      C.jmethodID
 	postFrameCallback  C.jmethodID
 	setCursor          C.jmethodID
+	setNavigationColor C.jmethodID
+	setStatusColor     C.jmethodID
 }
 
 // ViewEvent is sent whenever the Window's underlying Android view
@@ -220,6 +226,8 @@ func Java_org_gioui_GioView_onCreateView(env *C.JNIEnv, class C.jclass, view C.j
 		m.hideTextInput = getMethodID(env, class, "hideTextInput", "()V")
 		m.postFrameCallback = getMethodID(env, class, "postFrameCallback", "()V")
 		m.setCursor = getMethodID(env, class, "setCursor", "(I)V")
+		m.setNavigationColor = getMethodID(env, class, "setNavigationColor", "(II)V")
+		m.setStatusColor = getMethodID(env, class, "setStatusColor", "(II)V")
 	})
 	view = C.gio_jni_NewGlobalRef(env, view)
 	wopts := <-mainWindow.out
@@ -235,6 +243,7 @@ func Java_org_gioui_GioView_onCreateView(env *C.JNIEnv, class C.jclass, view C.j
 	handle := C.jlong(view)
 	views[handle] = w
 	w.loadConfig(env, class)
+	w.Option(wopts.opts)
 	applyStateDiff(env, view, windowState{}, w.state)
 	w.setStage(system.StagePaused)
 	w.callbacks.Event(ViewEvent{View: uintptr(view)})
@@ -676,7 +685,18 @@ func (w *window) ReadClipboard() {
 	})
 }
 
-func (w *window) Option(opts *Options) {}
+func (w *window) Option(opts *Options) {
+	if o := opts.NavigationColor; o != nil {
+		w.setState(func(state *windowState) {
+			state.navigationColor = o
+		})
+	}
+	if o := opts.StatusColor; o != nil {
+		w.setState(func(state *windowState) {
+			state.statusColor = o
+		})
+	}
+}
 
 func (w *window) SetCursor(name pointer.CursorName) {
 	w.setState(func(state *windowState) {
@@ -703,6 +723,12 @@ func applyStateDiff(env *C.JNIEnv, view C.jobject, old, state windowState) {
 	if state.cursor != nil && old.cursor != state.cursor {
 		setCursor(env, view, *state.cursor)
 	}
+	if state.navigationColor != nil && old.navigationColor != state.navigationColor {
+		setNavigationColor(env, view, *state.navigationColor)
+	}
+	if state.statusColor != nil && old.statusColor != state.statusColor {
+		setStatusColor(env, view, *state.statusColor)
+	}
 }
 
 func setCursor(env *C.JNIEnv, view C.jobject, name pointer.CursorName) {
@@ -728,6 +754,20 @@ func setCursor(env *C.JNIEnv, view C.jobject, name pointer.CursorName) {
 	callVoidMethod(env, view, gioView.setCursor, jvalue(curID))
 }
 
+func setStatusColor(env *C.JNIEnv, view C.jobject, color color.NRGBA) {
+	callVoidMethod(env, view, gioView.setStatusColor,
+		jvalue(uint32(color.A)<<24|uint32(color.R)<<16|uint32(color.G)<<8|uint32(color.B)),
+		jvalue(int(f32color.LinearFromSRGB(color).Luminance()*255)),
+	)
+}
+
+func setNavigationColor(env *C.JNIEnv, view C.jobject, color color.NRGBA) {
+	callVoidMethod(env, view, gioView.setNavigationColor,
+		jvalue(uint32(color.A)<<24|uint32(color.R)<<16|uint32(color.G)<<8|uint32(color.B)),
+		jvalue(int(f32color.LinearFromSRGB(color).Luminance()*255)),
+	)
+}
+
 // Close the window. Not implemented for Android.
 func (w *window) Close() {}
 

app/internal/wm/os_js.go

@@ -3,7 +3,10 @@
 package wm
 
 import (
+	"fmt"
+	"gioui.org/internal/f32color"
 	"image"
+	"image/color"
 	"strings"
 	"sync"
 	"syscall/js"
@@ -22,6 +25,7 @@ import (
 type window struct {
 	window                js.Value
 	document              js.Value
+	head                  js.Value
 	clipboard             js.Value
 	cnv                   js.Value
 	tarea                 js.Value
@@ -61,6 +65,7 @@ func NewWindow(win Callbacks, opts *Options) error {
 		document:  doc,
 		tarea:     tarea,
 		window:    js.Global().Get("window"),
+		head:      doc.Get("head"),
 		clipboard: js.Global().Get("navigator").Get("clipboard"),
 	}
 	w.requestAnimationFrame = w.window.Get("requestAnimationFrame")
@@ -486,6 +491,9 @@ func (w *window) Option(opts *Options) {
 	if o := opts.WindowMode; o != nil {
 		w.windowMode(*o)
 	}
+	if o := opts.NavigationColor; o != nil {
+		w.navigationColor(*o)
+	}
 }
 
 func (w *window) SetCursor(name pointer.CursorName) {
@@ -567,7 +575,7 @@ func (w *window) config() (int, int, system.Insets, unit.Metric) {
 func (w *window) windowMode(mode WindowMode) {
 	switch mode {
 	case Windowed:
-		if fs := w.document.Get("fullscreenElement"); !fs.Truthy() {
+		if !w.document.Get("fullscreenElement").Truthy() {
 			return // Browser is already Windowed.
 		}
 		if !w.document.Get("exitFullscreen").Truthy() {
@@ -583,6 +591,17 @@ func (w *window) windowMode(mode WindowMode) {
 	}
 }
 
+func (w *window) navigationColor(c color.NRGBA) {
+	theme := w.head.Call("querySelector", `meta[name="theme-color"]`)
+	if !theme.Truthy() {
+		theme = w.document.Call("createElement", "meta")
+		theme.Set("name", "theme-color")
+		w.head.Call("appendChild", theme)
+	}
+	rgba := f32color.NRGBAToRGBA(c)
+	theme.Set("content", fmt.Sprintf("#%06X", []uint8{rgba.R, rgba.G, rgba.B}))
+}
+
 func Main() {
 	select {}
 }

app/internal/wm/window.go

@@ -6,6 +6,7 @@ package wm
 
 import (
 	"errors"
+	"image/color"
 
 	"gioui.org/gpu"
 	"gioui.org/io/event"
@@ -25,6 +26,8 @@ type Options struct {
 	MaxSize         *Size
 	Title           *string
 	WindowMode      *WindowMode
+	StatusColor     *color.NRGBA
+	NavigationColor *color.NRGBA
 }
 
 type WindowMode uint8

app/window.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"image"
+	"image/color"
 	"time"
 
 	"gioui.org/io/event"
@@ -525,4 +526,18 @@ func MinSize(w, h unit.Value) Option {
 	}
 }
 
+// StatusColor sets the color of the Android status bar.
+func StatusColor(color color.NRGBA) Option {
+	return func(opts *wm.Options) {
+		opts.StatusColor = &color
+	}
+}
+
+// NavigationColor sets the color of the navigation bar on Android, or the address bar in browsers.
+func NavigationColor(color color.NRGBA) Option {
+	return func(opts *wm.Options) {
+		opts.NavigationColor = &color
+	}
+}
+
 func (driverEvent) ImplementsEvent() {}