egui/examples
Jay Oster ea89c2935e
Android support for eframe (#5318)
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Android support is "almost there". This PR pushes it just a bit further
by allowing `eframe` to be used on Android. It works by smuggling the
`AndroidApp` required by `winit` through `NativeOptions`.

The example isn't great because it doesn't leave space on the display
for Android's top status bar or the lower navigation bar. I don't know
what to do about that, yet. This is as far as I've managed to get it
working.

Another problem is that the development environment setup is completely
awful for Android unless you happen to already be a full-time Android
developer with everything configured on your build host. As a Rustacean,
this makes me very sad.

I've had some luck moving all of that mess to a container, adapted from
https://github.com/SergioRibera/docker-rust-android. It takes care of
all of the build dependencies, Android SDK, and the `cargo-apk` patches
for bugs that I hit while getting the example to work on my device. (I
also had to install an adb driver on my host and downloaded the Android
platform-tools to get access to `adb`. An alternative is exposing the
USB device to Docker. On Windows hosts, that means [installing
`usbipd`](https://learn.microsoft.com/en-us/windows/wsl/connect-usb). A
second alternative is using an `mtp` client to upload the APK as a file
with USB file transfer enabled, then manually install it through the
device's file manager.)

I'm not including the docker stuff in this PR, but here are the files
and instructions for future reference (and it will probably simplify
manual testing and CI, FWIW!)

<details><summary><code>Dockerfile</code></summary>

```dockerfile
FROM rust:1.76.0-slim

# Variable arguments
ARG JAVA_VERSION=17
ARG NDK_VERSION=25.1.8937393
ARG BUILDTOOLS_VERSION=30.0.0
ARG PLATFORM_VERSION=android-30
ARG CLITOOLS_VERSION=8512546_latest

# Install Android requirements
RUN apt-get update -yqq && \
    apt-get install -y --no-install-recommends \
    libcurl4-openssl-dev libssl-dev pkg-config build-essential git python3 wget zip unzip openjdk-${JAVA_VERSION}-jdk && \
    apt-get clean && \
    rm -rf /var/lib/apt/lists/*

# Install android targets
RUN rustup target add armv7-linux-androideabi aarch64-linux-android

# Install cargo-apk
RUN git clone -b fix/bin-targets-workspace-members https://github.com/parasyte/cargo-apk.git /tmp/cargo-apk && \
    cargo install --path /tmp/cargo-apk/cargo-apk

# Generate Environment Variables
ENV JAVA_VERSION=${JAVA_VERSION}
ENV ANDROID_HOME=/opt/Android
ENV NDK_HOME=/opt/Android/ndk/${NDK_VERSION}
ENV ANDROID_NDK_ROOT=${NDK_HOME}
ENV PATH=$PATH:${ANDROID_HOME}:${ANDROID_NDK_ROOT}:${ANDROID_HOME}/build-tools/${BUILDTOOLS_VERSION}:${ANDROID_HOME}/cmdline-tools/bin

# Install command line tools
RUN mkdir -p ${ANDROID_HOME}/cmdline-tools && \
    wget -qc "https://dl.google.com/android/repository/commandlinetools-linux-${CLITOOLS_VERSION}.zip" -P /tmp && \
    unzip -d ${ANDROID_HOME} /tmp/commandlinetools-linux-${CLITOOLS_VERSION}.zip && \
    rm -fr /tmp/commandlinetools-linux-${CLITOOLS_VERSION}.zip
# Install sdk requirements
RUN echo y | sdkmanager --sdk_root=${ANDROID_HOME} --install \
    "build-tools;${BUILDTOOLS_VERSION}" "ndk;${NDK_VERSION}" "platforms;${PLATFORM_VERSION}"

# Create APK keystore for debug profile
# Adapted from caa806283d/ndk-build/src/ndk.rs (L393-L423)
RUN keytool -genkey -v -keystore ${HOME}/.android/debug.keystore -storepass android -alias androiddebugkey \
    -keypass android -dname 'CN=Android Debug,O=Android,C=US' -keyalg RSA -keysize 2048 -validity 10000

# Cleanup
RUN rm -rf /tmp/*

WORKDIR /src

ENTRYPOINT [ "cargo", "apk", "build" ]
```
</details>

<details><summary><code>.dockerignore</code></summary>

```ignore
# Ignore everything, only the Dockerfile is needed to build the container
*
```
</details>

```sh
docker build -t rust-android:latest .
docker run --rm -it -v "$PWD:/src" rust-android:latest -p hello_android
adb install target/debug/apk/hello_android.apk
```

* Part of #2066
* [x] I have followed the instructions in the PR template
2024-12-12 19:24:26 +01:00
..
confirm_exit Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_3d_glow Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_font Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_font_style Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_keypad Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_style Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
custom_window_frame Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
file_dialog Update some crates to fix CI (#5456) 2024-12-10 17:16:38 +01:00
hello_android Android support for eframe (#5318) 2024-12-12 19:24:26 +01:00
hello_world Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
hello_world_par Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
hello_world_simple Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
images Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
keyboard_events Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
multiple_viewports Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
popups Add `ComboBox::close_behavior` (#5305) 2024-10-29 12:39:44 +01:00
puffin_profiler Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
screenshot Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
serial_windows Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
user_attention Update MSRV to 1.80 (#5457) 2024-12-10 16:09:03 +01:00
README.md examples/README.md: explain that the examples are for master 2023-02-08 20:34:43 +01:00
run_all.sh Fix up some examples (#3614) 2023-11-23 12:58:44 +01:00

README.md

egui and eframe examples

All the examples in this folder uses eframe to set up a window for egui. Some examples are specific to eframe, but many are applicable to any egui integration.

There are a lot more examples at https://www.egui.rs, and it has links to the source code of each example.

Also check out the official docs at https://docs.rs/egui and https://docs.rs/eframe.

Note that all the examples on master are for the latest master version of egui.

If you want to look for examples for a specific version of egui, go to that tag, e.g. https://github.com/emilk/egui/tree/latest/examples.