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Merged
whitebelyash merged 1 commit into from
Sep 15, 2026
Merged

android: implement MessageBox through jni-bindings #2

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204 changes: 200 additions & 4 deletions jni_bindings/src/main/java/git/mojo/sdl/SDLActivity.java
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Original file line number Diff line number Diff line change
Expand Up @@ -2,27 +2,37 @@

import static android.content.Context.UI_MODE_SERVICE;

import static git.mojo.sdl.SDL.mContext;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.UiModeManager;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.PorterDuff;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.LocaleList;
import android.os.ParcelFileDescriptor;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.SparseArray;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.Surface;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;

Expand All @@ -35,8 +45,6 @@ public class SDLActivity {
private static Runnable initCallback;

protected static Surface mSurface;
protected static Activity mContext;

private static SDLClipboard mClipboard;

public static void initialize() {
Expand Down Expand Up @@ -430,4 +438,192 @@ public static String formatLocale(Locale locale) {
}
return result;
}

/** Result of current messagebox. Also used for blocking the calling thread. */
protected static final int[] messageboxSelection = new int[1];

/**
* Shows the messagebox from UI thread and block calling thread.
* buttonFlags, buttonIds and buttonTexts must have same length.
* @param buttonFlags array containing flags for every button.
* @param buttonIds array containing id for every button.
* @param buttonTexts array containing text for every button.
* @param colors null for default or array of length 5 containing colors.
* @return button id or -1.
*/
public static int showMessageBox(
final int flags,
final String title,
final String message,
final int[] buttonFlags,
final int[] buttonIds,
final String[] buttonTexts,
final int[] colors) {

messageboxSelection[0] = -1;

// sanity checks

if ((buttonFlags.length != buttonIds.length) && (buttonIds.length != buttonTexts.length)) {
return -1; // implementation broken
}

// collect arguments for Dialog

final Bundle args = new Bundle();
args.putInt("flags", flags);
args.putString("title", title);
args.putString("message", message);
args.putIntArray("buttonFlags", buttonFlags);
args.putIntArray("buttonIds", buttonIds);
args.putStringArray("buttonTexts", buttonTexts);
args.putIntArray("colors", colors);

// trigger Dialog creation on UI thread

runOnUiThread(() -> createMessageBox(args));

// block the calling thread

synchronized (messageboxSelection) {
try {
messageboxSelection.wait();
} catch (InterruptedException ex) {
ex.printStackTrace();
return -1;
}
}

// return selected value

return messageboxSelection[0];
}

private static void runOnUiThread(Runnable runnable) {
mContext.runOnUiThread(runnable);
}

private static void createMessageBox(Bundle args) {

// TODO set values from "flags" to messagebox dialog

// get colors

int[] colors = args.getIntArray("colors");
int backgroundColor;
int textColor;
int buttonBorderColor;
int buttonBackgroundColor;
int buttonSelectedColor;
if (colors != null) {
int i = -1;
backgroundColor = colors[++i];
textColor = colors[++i];
buttonBorderColor = colors[++i];
buttonBackgroundColor = colors[++i];
buttonSelectedColor = colors[++i];
} else {
backgroundColor = Color.TRANSPARENT;
textColor = Color.TRANSPARENT;
buttonBorderColor = Color.TRANSPARENT;
buttonBackgroundColor = Color.TRANSPARENT;
buttonSelectedColor = Color.TRANSPARENT;
}

// create dialog with title and a listener to wake up calling thread

final AlertDialog dialog = new AlertDialog.Builder(mContext).create();
dialog.setTitle(args.getString("title"));
dialog.setCancelable(false);
dialog.setOnDismissListener(unused -> {
synchronized (messageboxSelection) {
messageboxSelection.notify();
}
});

// create text

TextView message = new TextView(mContext);
message.setGravity(Gravity.CENTER);
message.setText(args.getString("message"));
if (textColor != Color.TRANSPARENT) {
message.setTextColor(textColor);
}

// create buttons

int[] buttonFlags = args.getIntArray("buttonFlags");
int[] buttonIds = args.getIntArray("buttonIds");
String[] buttonTexts = args.getStringArray("buttonTexts");

final SparseArray<Button> mapping = new SparseArray<Button>();

LinearLayout buttons = new LinearLayout(mContext);
buttons.setOrientation(LinearLayout.HORIZONTAL);
buttons.setGravity(Gravity.CENTER);
for (int i = 0; i < buttonTexts.length; ++i) {
Button button = new Button(mContext);
final int id = buttonIds[i];
button.setOnClickListener(v -> {
messageboxSelection[0] = id;
dialog.dismiss();
});
if (buttonFlags[i] != 0) {
// see SDL_messagebox.h
if ((buttonFlags[i] & 0x00000001) != 0) {
mapping.put(KeyEvent.KEYCODE_ENTER, button);
}
if ((buttonFlags[i] & 0x00000002) != 0) {
mapping.put(KeyEvent.KEYCODE_ESCAPE, button); /* API 11 */
}
}
button.setText(buttonTexts[i]);
if (textColor != Color.TRANSPARENT) {
button.setTextColor(textColor);
}
if (buttonBorderColor != Color.TRANSPARENT) {
// TODO set color for border of messagebox button
}
if (buttonBackgroundColor != Color.TRANSPARENT) {
Drawable drawable = button.getBackground();
if (drawable == null) {
// setting the color this way removes the style
button.setBackgroundColor(buttonBackgroundColor);
} else {
// setting the color this way keeps the style (gradient, padding, etc.)
drawable.setColorFilter(buttonBackgroundColor, PorterDuff.Mode.MULTIPLY);
}
}
if (buttonSelectedColor != Color.TRANSPARENT) {
// TODO set color for selected messagebox button
}
buttons.addView(button);
}

// create content

LinearLayout content = new LinearLayout(mContext);
content.setOrientation(LinearLayout.VERTICAL);
content.addView(message);
content.addView(buttons);
if (backgroundColor != Color.TRANSPARENT) {
content.setBackgroundColor(backgroundColor);
}

// add content to dialog and return

dialog.setView(content);
dialog.setOnKeyListener((d, keyCode, event) -> {
Button button = mapping.get(keyCode);
if (button != null) {
if (event.getAction() == KeyEvent.ACTION_UP) {
button.performClick();
}
return true; // also for ignored actions
}
return false;
});

dialog.show();
}
}
18 changes: 4 additions & 14 deletions src/core/android/SDL_android.c
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Original file line number Diff line number Diff line change
Expand Up @@ -98,6 +98,7 @@ static jmethodID midSendMessage;
static jmethodID midNotifyInit;
static jmethodID midOpenFileDescriptor;
static jmethodID midManualBackButton;
static jmethodID midShowMessageBox;
#ifndef SDL_DIALOG_DISABLED
static jmethodID midShowFileDialog;
#endif // !SDL_DIALOG_DISABLED
Expand Down Expand Up @@ -674,6 +675,7 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
midNotifyInit = (*env)->GetStaticMethodID(env, mActivityClass, "onSDLInit", "()V");
midOpenFileDescriptor = (*env)->GetStaticMethodID(env, mActivityClass, "openFileDescriptor", "(Ljava/lang/String;Ljava/lang/String;)I");
midManualBackButton = (*env)->GetStaticMethodID(env, mActivityClass, "manualBackButton", "()V");
midShowMessageBox = (*env)->GetStaticMethodID(env, mActivityClass, "showMessageBox", "(ILjava/lang/String;Ljava/lang/String;[I[I[Ljava/lang/String;[I)I");
#ifndef SDL_DIALOG_DISABLED
midShowFileDialog = (*env)->GetStaticMethodID(env, mActivityClass, "showFileDialog", "([Ljava/lang/String;ZILjava/lang/String;I)Z");
#endif // !SDL_DIALOG_DISABLED
Expand All @@ -692,6 +694,7 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativeSetupJNI)(JNIEnv *env, jclass cl
!midSendMessage ||
!midOpenFileDescriptor ||
!midManualBackButton ||
!midShowMessageBox ||
#ifndef SDL_DIALOG_DISABLED
!midShowFileDialog ||
#endif
Expand Down Expand Up @@ -3082,16 +3085,7 @@ bool Android_JNI_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *b
colors = NULL;
}

(*env)->DeleteLocalRef(env, clazz);

// context = SDLActivity.getContext();
context = (*env)->CallStaticObjectMethod(env, mActivityClass, midGetContext);

clazz = (*env)->GetObjectClass(env, context);

mid = (*env)->GetMethodID(env, clazz,
"messageboxShowMessageBox", "(ILjava/lang/String;Ljava/lang/String;[I[I[Ljava/lang/String;[I)I");
*buttonID = (*env)->CallIntMethod(env, context, mid,
*buttonID = (*env)->CallStaticIntMethod(env, mActivityClass, midShowMessageBox,
(jint)messageboxdata->flags,
title,
message,
Expand All @@ -3100,11 +3094,7 @@ bool Android_JNI_ShowMessageBox(const SDL_MessageBoxData *messageboxdata, int *b
button_texts,
colors);

(*env)->DeleteLocalRef(env, context);
(*env)->DeleteLocalRef(env, clazz);

// delete parameters

(*env)->DeleteLocalRef(env, title);
(*env)->DeleteLocalRef(env, message);
(*env)->DeleteLocalRef(env, button_flags);
Expand Down
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