Add collapsible left navigation to prepaint APK

android-prepaint/app/src/main/AndroidManifest.xml

@@ -11,6 +11,7 @@
         android:required="false" />
 
     <application
+        android:name=".PrepaintApplication"
         android:allowBackup="false"
         android:label="IB Prepaint"
         android:supportsRtl="true"

android-prepaint/app/src/main/java/org/isomorphisms/ib/prepaint/PrepaintApplication.java

@@ -0,0 +1,43 @@
+package org.isomorphisms.ib.prepaint;
+
+import android.app.Activity;
+import android.app.Application;
+import android.os.Bundle;
+
+import java.util.WeakHashMap;
+
+public final class PrepaintApplication extends Application
+        implements Application.ActivityLifecycleCallbacks {
+    private final WeakHashMap<Activity, PrepaintNavigation> installed = new WeakHashMap<>();
+
+    @Override
+    public void onCreate() {
+        super.onCreate();
+        registerActivityLifecycleCallbacks(this);
+    }
+
+    @Override
+    public void onActivityStarted(Activity activity) {
+        if (!(activity instanceof PrepaintActivity) || installed.containsKey(activity)) {
+            return;
+        }
+        PrepaintNavigation navigation = PrepaintNavigation.install(activity);
+        if (navigation != null) {
+            installed.put(activity, navigation);
+        }
+    }
+
+    @Override
+    public void onActivityDestroyed(Activity activity) {
+        PrepaintNavigation navigation = installed.remove(activity);
+        if (navigation != null) {
+            navigation.destroy();
+        }
+    }
+
+    @Override public void onActivityCreated(Activity activity, Bundle state) { }
+    @Override public void onActivityResumed(Activity activity) { }
+    @Override public void onActivityPaused(Activity activity) { }
+    @Override public void onActivityStopped(Activity activity) { }
+    @Override public void onActivitySaveInstanceState(Activity activity, Bundle state) { }
+}

android-prepaint/app/src/main/java/org/isomorphisms/ib/prepaint/PrepaintNavigation.java

@@ -0,0 +1,200 @@
+package org.isomorphisms.ib.prepaint;
+
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.animation.ValueAnimator;
+import android.app.Activity;
+import android.graphics.Typeface;
+import android.view.Gravity;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.Button;
+import android.widget.FrameLayout;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+final class PrepaintNavigation {
+    static final long TRANSITION_MILLIS = 150;
+    private static final int NAVIGATION_WIDTH_DP = 136;
+
+    private final LinearLayout navigation;
+    private final Button toggle;
+    private final int openWidth;
+
+    private boolean open = true;
+    private ValueAnimator animator;
+
+    private PrepaintNavigation(LinearLayout navigation, Button toggle, int openWidth) {
+        this.navigation = navigation;
+        this.toggle = toggle;
+        this.openWidth = openWidth;
+        updateToggle();
+    }
+
+    static PrepaintNavigation install(Activity activity) {
+        ViewGroup content = activity.findViewById(android.R.id.content);
+        if (!(content instanceof FrameLayout) || content.getChildCount() != 1) {
+            return null;
+        }
+        View existing = content.getChildAt(0);
+        if (!(existing instanceof LinearLayout)) {
+            return null;
+        }
+        LinearLayout root = (LinearLayout) existing;
+        if (root.getChildCount() == 0 || !(root.getChildAt(0) instanceof LinearLayout)) {
+            return null;
+        }
+        LinearLayout chrome = (LinearLayout) root.getChildAt(0);
+        Button openButton = findButton(chrome, "Open");
+        Button replayButton = findButton(chrome, "Replay");
+        if (openButton == null || replayButton == null) {
+            return null;
+        }
+
+        chrome.removeView(openButton);
+        chrome.removeView(replayButton);
+        content.removeView(root);
+
+        LinearLayout shell = new LinearLayout(activity);
+        shell.setOrientation(LinearLayout.HORIZONTAL);
+        shell.setBackgroundColor(activity.getColor(R.color.prepaint_background));
+
+        LinearLayout navigation = new LinearLayout(activity);
+        navigation.setOrientation(LinearLayout.VERTICAL);
+        navigation.setGravity(Gravity.TOP);
+        navigation.setPadding(dp(activity, 8), dp(activity, 10), dp(activity, 8), dp(activity, 10));
+        navigation.setBackgroundColor(activity.getColor(R.color.prepaint_surface));
+
+        TextView heading = new TextView(activity);
+        heading.setText("IB");
+        heading.setTextSize(12);
+        heading.setTextColor(activity.getColor(R.color.prepaint_secondary));
+        heading.setTypeface(Typeface.createFromAsset(activity.getAssets(), "fonts/Hack-Regular.ttf"));
+        heading.setIncludeFontPadding(false);
+        LinearLayout.LayoutParams headingLayout = new LinearLayout.LayoutParams(
+                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
+        headingLayout.setMargins(dp(activity, 7), 0, dp(activity, 7), dp(activity, 10));
+        navigation.addView(heading, headingLayout);
+
+        navigation.addView(openButton, navigationButtonLayout(activity, 0));
+        navigation.addView(replayButton, navigationButtonLayout(activity, 7));
+
+        Button toggle = new Button(activity);
+        toggle.setAllCaps(false);
+        toggle.setTextColor(activity.getColor(R.color.prepaint_foreground));
+        toggle.setTextSize(14);
+        toggle.setTypeface(Typeface.createFromAsset(activity.getAssets(), "fonts/Hack-Regular.ttf"));
+        toggle.setMinHeight(0);
+        toggle.setMinWidth(0);
+        toggle.setPadding(dp(activity, 10), dp(activity, 7), dp(activity, 10), dp(activity, 7));
+        toggle.setBackground(buttonBackground(activity));
+        toggle.setFocusable(true);
+        LinearLayout.LayoutParams toggleLayout = new LinearLayout.LayoutParams(
+                ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
+        toggleLayout.setMargins(0, 0, dp(activity, 8), 0);
+        chrome.addView(toggle, 0, toggleLayout);
+
+        int navigationWidth = dp(activity, NAVIGATION_WIDTH_DP);
+        shell.addView(navigation, new LinearLayout.LayoutParams(
+                navigationWidth, ViewGroup.LayoutParams.MATCH_PARENT));
+        shell.addView(root, new LinearLayout.LayoutParams(
+                0, ViewGroup.LayoutParams.MATCH_PARENT, 1));
+        content.addView(shell, new FrameLayout.LayoutParams(
+                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
+
+        PrepaintNavigation installed = new PrepaintNavigation(navigation, toggle, navigationWidth);
+        toggle.setOnClickListener(ignored -> installed.setOpen(!installed.open));
+        return installed;
+    }
+
+    private void setOpen(boolean wantedOpen) {
+        open = wantedOpen;
+        updateToggle();
+        cancelAnimator();
+
+        int targetWidth = open ? openWidth : 0;
+        ViewGroup.LayoutParams layout = navigation.getLayoutParams();
+        int startWidth = layout.width;
+        if (open) {
+            navigation.setVisibility(View.VISIBLE);
+        }
+
+        if (startWidth == targetWidth || !ValueAnimator.areAnimatorsEnabled()) {
+            setWidth(targetWidth);
+            navigation.setVisibility(open ? View.VISIBLE : View.GONE);
+            return;
+        }
+
+        ValueAnimator next = ValueAnimator.ofInt(startWidth, targetWidth);
+        animator = next;
+        next.setDuration(TRANSITION_MILLIS);
+        next.addUpdateListener(value -> setWidth((Integer) value.getAnimatedValue()));
+        next.addListener(new AnimatorListenerAdapter() {
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                if (animator != animation) {
+                    return;
+                }
+                animator = null;
+                setWidth(targetWidth);
+                if (!open) {
+                    navigation.setVisibility(View.GONE);
+                }
+            }
+        });
+        next.start();
+    }
+
+    private void updateToggle() {
+        toggle.setText(open ? "<" : ">");
+        toggle.setContentDescription(open ? "Close navigation" : "Open navigation");
+    }
+
+    private void setWidth(int width) {
+        ViewGroup.LayoutParams layout = navigation.getLayoutParams();
+        layout.width = width;
+        navigation.setLayoutParams(layout);
+    }
+
+    private void cancelAnimator() {
+        if (animator == null) {
+            return;
+        }
+        ValueAnimator old = animator;
+        animator = null;
+        old.cancel();
+    }
+
+    void destroy() {
+        cancelAnimator();
+    }
+
+    private static Button findButton(LinearLayout parent, String text) {
+        for (int index = 0; index < parent.getChildCount(); index += 1) {
+            View child = parent.getChildAt(index);
+            if (child instanceof Button && text.contentEquals(((Button) child).getText())) {
+                return (Button) child;
+            }
+        }
+        return null;
+    }
+
+    private static LinearLayout.LayoutParams navigationButtonLayout(Activity activity, int top) {
+        LinearLayout.LayoutParams layout = new LinearLayout.LayoutParams(
+                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
+        layout.setMargins(0, dp(activity, top), 0, 0);
+        return layout;
+    }
+
+    private static android.graphics.drawable.GradientDrawable buttonBackground(Activity activity) {
+        android.graphics.drawable.GradientDrawable background =
+                new android.graphics.drawable.GradientDrawable();
+        background.setColor(activity.getColor(R.color.prepaint_rule));
+        background.setCornerRadius(dp(activity, 5));
+        return background;
+    }
+
+    private static int dp(Activity activity, int value) {
+        return Math.round(value * activity.getResources().getDisplayMetrics().density);
+    }
+}