Fix issue where soft keyboard overlaps extra keys or terminal in some cases

Check TermuxActivityRootView javadocs for details.

app/src/main/java/com/termux/app/TermuxActivity.java

@@ -30,6 +30,7 @@ import android.widget.ListView;
 import android.widget.Toast;
 
 import com.termux.R;
+import com.termux.app.terminal.TermuxActivityRootView;
 import com.termux.shared.termux.TermuxConstants;
 import com.termux.shared.termux.TermuxConstants.TERMUX_APP.TERMUX_ACTIVITY;
 import com.termux.app.activities.HelpActivity;
@@ -68,7 +69,6 @@ import androidx.viewpager.widget.ViewPager;
  */
 public final class TermuxActivity extends Activity implements ServiceConnection {
 
-
     /**
      * The connection to the {@link TermuxService}. Requested in {@link #onCreate(Bundle)} with a call to
      * {@link #bindService(Intent, ServiceConnection, int)}, and obtained and stored in
@@ -77,7 +77,7 @@ public final class TermuxActivity extends Activity implements ServiceConnection
     TermuxService mTermuxService;
 
     /**
-     * The main view of the activity showing the terminal. Initialized in onCreate().
+     * The {@link TerminalView} shown in  {@link TermuxActivity} that displays the terminal.
      */
     TerminalView mTerminalView;
 
@@ -103,6 +103,16 @@ public final class TermuxActivity extends Activity implements ServiceConnection
      */
     private TermuxAppSharedProperties mProperties;
 
+    /**
+     * The root view of the {@link TermuxActivity}.
+     */
+    TermuxActivityRootView mTermuxActivityRootView;
+
+    /**
+     * The space at the bottom of {@link @mTermuxActivityRootView} of the {@link TermuxActivity}.
+     */
+    View mTermuxActivityBottomSpaceView;
+
     /**
      * The terminal extra keys view.
      */
@@ -189,6 +199,10 @@ public final class TermuxActivity extends Activity implements ServiceConnection
             return;
         }
 
+        mTermuxActivityRootView = findViewById(R.id.activity_termux_root_view);
+        mTermuxActivityRootView.setActivity(this);
+        mTermuxActivityBottomSpaceView = findViewById(R.id.activity_termux_bottom_space_view);
+
         View content = findViewById(android.R.id.content);
         content.setOnApplyWindowInsetsListener((v, insets) -> {
             mNavBarHeight = insets.getSystemWindowInsetBottom();
@@ -241,6 +255,8 @@ public final class TermuxActivity extends Activity implements ServiceConnection
         if (mTermuxTerminalViewClient != null)
             mTermuxTerminalViewClient.onStart();
 
+        addTermuxActivityRootViewGlobalLayoutListener();
+
         registerTermuxActivityBroadcastReceiver();
     }
 
@@ -277,6 +293,8 @@ public final class TermuxActivity extends Activity implements ServiceConnection
         if (mTermuxTerminalViewClient != null)
             mTermuxTerminalViewClient.onStop();
 
+        removeTermuxActivityRootViewGlobalLayoutListener();
+
         unregisterTermuxActivityBroadcastReceiever();
         getDrawer().closeDrawers();
     }
@@ -390,6 +408,17 @@ public final class TermuxActivity extends Activity implements ServiceConnection
 
 
 
+    public void addTermuxActivityRootViewGlobalLayoutListener() {
+        getTermuxActivityRootView().getViewTreeObserver().addOnGlobalLayoutListener(getTermuxActivityRootView());
+    }
+
+    public void removeTermuxActivityRootViewGlobalLayoutListener() {
+        if (getTermuxActivityRootView() != null)
+            getTermuxActivityRootView().getViewTreeObserver().removeOnGlobalLayoutListener(getTermuxActivityRootView());
+    }
+
+
+
     private void setTermuxTerminalViewAndClients() {
         // Set termux terminal view and session clients
         mTermuxTerminalSessionClient = new TermuxTerminalSessionClient(this);
@@ -679,6 +708,14 @@ public final class TermuxActivity extends Activity implements ServiceConnection
         return mNavBarHeight;
     }
 
+    public TermuxActivityRootView getTermuxActivityRootView() {
+        return mTermuxActivityRootView;
+    }
+
+    public View getTermuxActivityBottomSpaceView() {
+        return mTermuxActivityBottomSpaceView;
+    }
+
     public ExtraKeysView getExtraKeysView() {
         return mExtraKeysView;
     }

app/src/main/java/com/termux/app/terminal/TermuxActivityRootView.java

@@ -0,0 +1,227 @@
+package com.termux.app.terminal;
+
+import android.content.Context;
+import android.graphics.Rect;
+import android.inputmethodservice.InputMethodService;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.ViewTreeObserver;
+import android.view.inputmethod.EditorInfo;
+import android.widget.FrameLayout;
+import android.widget.LinearLayout;
+
+import androidx.annotation.Nullable;
+
+import com.termux.app.TermuxActivity;
+import com.termux.shared.logger.Logger;
+import com.termux.shared.view.ViewUtils;
+
+
+/**
+ * The {@link TermuxActivity} relies on {@link android.view.WindowManager.LayoutParams#SOFT_INPUT_ADJUST_RESIZE)}
+ * set by {@link TermuxTerminalViewClient#setSoftKeyboardState(boolean, boolean)} to automatically
+ * resize the view and push the terminal up when soft keyboard is opened. However, this does not
+ * always work properly. When `enforce-char-based-input=true` is set in `termux.properties`
+ * and {@link com.termux.view.TerminalView#onCreateInputConnection(EditorInfo)} sets the inputType
+ * to `InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD | InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS`
+ * instead of the default `InputType.TYPE_NULL` for termux, some keyboards may still show suggestions.
+ * Gboard does too, but only when text is copied and clipboard suggestions **and** number keys row
+ * toggles are enabled in its settings. When number keys row toggle is not enabled, Gboard will still
+ * show the row but will switch it with suggestions if needed. If its enabled, then number keys row
+ * is always shown and suggestions are shown in an additional row on top of it. This additional row is likely
+ * part of the candidates view returned by the keyboard app in {@link InputMethodService#onCreateCandidatesView()}.
+ *
+ * With the above configuration, the additional clipboard suggestions row partially covers the
+ * extra keys/terminal. Reopening the keyboard/activity does not fix the issue. This is either a bug
+ * in the Android OS where it does not consider the candidate's view height in its calculation to push
+ * up the view or because Gboard does not include the candidate's view height in the height reported
+ * to android that should be used, hence causing an overlap.
+ *
+ * Gboard logs the following entry to `logcat` when its opened with or without the suggestions bar showing:
+ * I/KeyboardViewUtil: KeyboardViewUtil.calculateMaxKeyboardBodyHeight():62 leave 500 height for app when screen height:2392, header height:176 and isFullscreenMode:false, so the max keyboard body height is:1716
+ * where `keyboard_height = screen_height - height_for_app - header_height` (62 is a hardcoded value in Gboard source code and may be a version number)
+ * So this may in fact be due to Gboard but https://stackoverflow.com/questions/57567272 suggests
+ * otherwise. Another similar report https://stackoverflow.com/questions/66761661.
+ * Also check https://github.com/termux/termux-app/issues/1539.
+ *
+ * This overlap may happen even without `enforce-char-based-input=true` for keyboards with extended layouts
+ * like number row, etc.
+ *
+ * To fix these issues, `activity_termux.xml` has the constant 1sp transparent
+ * `activity_termux_bottom_space_view` View at the bottom. This will appear as a line matching the
+ * activity theme. When {@link TermuxActivity} {@link ViewTreeObserver.OnGlobalLayoutListener} is
+ * called when any of the sub view layouts change,  like keyboard opening/closing keyboard,
+ * extra keys/input view switched, etc, we check if the bottom space view is visible or not.
+ * If its not, then we add a margin to the bottom of the root view, so that the keyboard does not
+ * overlap the extra keys/terminal, since the margin will push up the view. By default the margin
+ * added is equal to the height of the hidden part of extra keys/terminal. For Gboard's case, the
+ * hidden part equals the `header_height`. The updates to margins may cause a jitter in some cases
+ * when the view is redrawn if the margin is incorrect, but logic has been implemented to avoid that.
+ */
+public class TermuxActivityRootView extends LinearLayout implements ViewTreeObserver.OnGlobalLayoutListener {
+
+    public TermuxActivity mActivity;
+    public Integer marginBottom;
+    public Integer lastMarginBottom;
+
+    /** Log root view events. */
+    private boolean ROOT_VIEW_LOGGING_ENABLED = false;
+
+    private static final String LOG_TAG = "TermuxActivityRootView";
+
+    public TermuxActivityRootView(Context context) {
+        super(context);
+
+    }
+
+    public TermuxActivityRootView(Context context, @Nullable AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public TermuxActivityRootView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+    public void setActivity(TermuxActivity activity) {
+        mActivity = activity;
+    }
+
+    /**
+     * Sets whether root view logging is enabled or not.
+     *
+     * @param value The boolean value that defines the state.
+     */
+    public void setIsRootViewLoggingEnabled(boolean value) {
+        ROOT_VIEW_LOGGING_ENABLED = value;
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+
+        if (marginBottom != null) {
+            if (ROOT_VIEW_LOGGING_ENABLED)
+                Logger.logVerbose(LOG_TAG, "onMeasure: Setting bottom margin to " + marginBottom);
+            ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) getLayoutParams();
+            params.setMargins(0, 0, 0, marginBottom);
+            setLayoutParams(params);
+            marginBottom = null;
+            requestLayout();
+        }
+    }
+
+    @Override
+    public void onGlobalLayout() {
+        if (mActivity == null || !mActivity.isVisible()) return;
+
+        View bottomSpaceView = mActivity.getTermuxActivityBottomSpaceView();
+        if (bottomSpaceView == null) return;
+
+        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) getLayoutParams();
+
+        // Get the position Rects of the bottom space view and the main window holding it
+        Rect[] windowAndViewRects = ViewUtils.getWindowAndViewRects(bottomSpaceView);
+        if (windowAndViewRects == null)
+            return;
+
+        Rect windowAvailableRect = windowAndViewRects[0];
+        Rect bottomSpaceViewRect = windowAndViewRects[1];
+
+        // If the bottomSpaceViewRect is inside the windowAvailableRect, then it must be completely visible
+        boolean isVisible = windowAvailableRect.contains(bottomSpaceViewRect);
+        boolean isVisibleBecauseMargin = (windowAvailableRect.bottom == bottomSpaceViewRect.bottom) && params.bottomMargin > 0;
+        boolean isVisibleBecauseExtraMargin = (bottomSpaceViewRect.bottom - windowAvailableRect.bottom) < 0;
+
+        if (ROOT_VIEW_LOGGING_ENABLED)
+            Logger.logVerbose(LOG_TAG, "onGlobalLayout: windowAvailableRect " + windowAvailableRect.bottom + ", bottomSpaceViewRect " + bottomSpaceViewRect.bottom + ", diff " + (bottomSpaceViewRect.bottom - windowAvailableRect.bottom) + ", bottom " + params.bottomMargin + ", isVisible " + isVisible + ", isVisibleBecauseMargin " + isVisibleBecauseMargin + ", isVisibleBecauseExtraMargin " + isVisibleBecauseExtraMargin);
+
+        // If the bottomSpaceViewRect is visible, then remove the margin if needed
+        if (isVisible) {
+            // If visible because of margin, i.e the bottom of bottomSpaceViewRect equals that of windowAvailableRect
+            // and a margin has been added
+            // Necessary so that we don't get stuck in an infinite loop since setting margin
+            // will call OnGlobalLayoutListener again and next time bottom space view
+            // will be visible and margin will be set to 0, which again will call
+            // OnGlobalLayoutListener...
+            // Calling addTermuxActivityRootViewGlobalLayoutListener with a delay fails to
+            // set appropriate margins when views are changed quickly since some changes
+            // may be missed.
+            if (isVisibleBecauseMargin) {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Visible due to margin");
+                // Once the view has been redrawn with new margin, we set margin back to 0 so that
+                // when next time onMeasure() is called, margin 0 is used. This is necessary for
+                // cases when view has been redrawn with new margin because bottom space view was
+                // hidden by keyboard and then view was redrawn again due to layout change (like
+                // keyboard symbol view is switched to), android will add margin below its new position
+                // if its greater than 0, which was already above the keyboard creating x2x margin.
+                marginBottom = 0;
+                return;
+            }
+
+            boolean setMargin = params.bottomMargin != 0;
+
+            // If visible because of extra margin, i.e the bottom of bottomSpaceViewRect is above that of windowAvailableRect
+            // onGlobalLayout: windowAvailableRect 1408, bottomSpaceViewRect 1232, diff -176, bottom 0, isVisible true, isVisibleBecauseMargin false, isVisibleBecauseExtraMargin false
+            // onGlobalLayout: Bottom margin already equals 0
+            if (isVisibleBecauseExtraMargin) {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Resetting margin since visible due to extra margin");
+                setMargin = true;
+                // lastMarginBottom must be invalid. May also happen when keyboards are changed.
+                lastMarginBottom = null;
+            }
+
+            if (setMargin) {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Setting bottom margin to 0");
+                params.setMargins(0, 0, 0, 0);
+                setLayoutParams(params);
+            } else {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Bottom margin already equals 0");
+                // This is done so that when next time onMeasure() is called, lastMarginBottom is used.
+                // This is done since we **expect** the keyboard to have same dimensions next time layout
+                // changes, so best set margin while view is drawn the first time, otherwise it will
+                // cause a jitter when OnGlobalLayoutListener is called with margin 0 and it sets the
+                // likely same lastMarginBottom again and requesting a redraw. Hopefully, this logic
+                // works fine for all cases.
+                marginBottom = lastMarginBottom;
+            }
+        }
+        // ELse find the part of the extra keys/terminal that is hidden and add a margin accordingly
+        else {
+            int pxHidden = bottomSpaceViewRect.bottom - windowAvailableRect.bottom;
+            if (ROOT_VIEW_LOGGING_ENABLED)
+                Logger.logVerbose(LOG_TAG, "onGlobalLayout: pxHidden " + pxHidden + ", bottom " + params.bottomMargin);
+
+            boolean setMargin = params.bottomMargin != pxHidden;
+
+            // If invisible despite margin, i.e a margin was added, but the bottom of bottomSpaceViewRect
+            // is still below that of windowAvailableRect, this will trigger OnGlobalLayoutListener
+            // again, so that margins are set properly. May happen when toolbar/extra keys is disabled
+            // and enabled from left drawer, just like case for isVisibleBecauseExtraMargin.
+            // onMeasure: Setting bottom margin to 176
+            // onGlobalLayout: windowAvailableRect 1232, bottomSpaceViewRect 1408, diff 176, bottom 176, isVisible false, isVisibleBecauseMargin false, isVisibleBecauseExtraMargin false
+            // onGlobalLayout: Bottom margin already equals 176
+            if ((bottomSpaceViewRect.bottom - windowAvailableRect.bottom) > 0) {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Force setting margin since not visible despite margin");
+                setMargin = true;
+            }
+
+            if (setMargin) {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Setting bottom margin to " + pxHidden);
+                params.setMargins(0, 0, 0, pxHidden);
+                setLayoutParams(params);
+                lastMarginBottom = pxHidden;
+            } else {
+                if (ROOT_VIEW_LOGGING_ENABLED)
+                    Logger.logVerbose(LOG_TAG, "onGlobalLayout: Bottom margin already equals " + pxHidden);
+            }
+        }
+    }
+
+}

app/src/main/java/com/termux/app/terminal/TermuxTerminalViewClient.java

@@ -79,10 +79,13 @@ public class TermuxTerminalViewClient extends TermuxTerminalViewClientBase {
      * Should be called when mActivity.onStart() is called
      */
     public void onStart() {
-
         // Set {@link TerminalView#TERMINAL_VIEW_KEY_LOGGING_ENABLED} value
         // Also required if user changed the preference from {@link TermuxSettings} activity and returns
-        mActivity.getTerminalView().setIsTerminalViewKeyLoggingEnabled(mActivity.getPreferences().isTerminalViewKeyLoggingEnabled());
+        boolean isTerminalViewKeyLoggingEnabled = mActivity.getPreferences().isTerminalViewKeyLoggingEnabled();
+        mActivity.getTerminalView().setIsTerminalViewKeyLoggingEnabled(isTerminalViewKeyLoggingEnabled);
+
+        // Piggyback on the terminal view key logging toggle for now, should add a separate toggle in future
+        mActivity.getTermuxActivityRootView().setIsRootViewLoggingEnabled(isTerminalViewKeyLoggingEnabled);
     }
 
     /**
@@ -459,7 +462,7 @@ public class TermuxTerminalViewClient extends TermuxTerminalViewClientBase {
                 mShowSoftKeyboardWithDelayOnce = true;
         } else {
             // Set flag to automatically push up TerminalView when keyboard is opened instead of showing over it
-            KeyboardUtils.setResizeTerminalViewForSoftKeyboardFlags(mActivity);
+            KeyboardUtils.setSoftInputModeAdjustResize(mActivity);
 
             // Clear any previous flags to disable soft keyboard in case setting updated
             KeyboardUtils.clearDisableSoftKeyboardFlags(mActivity);

app/src/main/res/layout/activity_termux.xml

@@ -1,9 +1,16 @@
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<com.termux.app.terminal.TermuxActivityRootView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:id="@+id/activity_termux_root_view"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     android:fitsSystemWindows="true">
 
+    <RelativeLayout
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="1"
+        android:orientation="vertical">
+
         <androidx.drawerlayout.widget.DrawerLayout
             android:id="@+id/drawer_layout"
             android:layout_width="match_parent"
@@ -77,4 +84,13 @@
             android:layout_height="37.5dp"
             android:background="@android:drawable/screen_background_dark_transparent"
             android:layout_alignParentBottom="true" />
-</RelativeLayout>
+
+    </RelativeLayout>
+
+    <View
+        android:id="@+id/activity_termux_bottom_space_view"
+        android:layout_width="match_parent"
+        android:layout_height="1dp"
+        android:background="@android:color/transparent" />
+
+</com.termux.app.terminal.TermuxActivityRootView>

termux-shared/src/main/java/com/termux/shared/view/KeyboardUtils.java

@@ -102,7 +102,7 @@ public class KeyboardUtils {
             activity.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
     }
 
-    public static void setResizeTerminalViewForSoftKeyboardFlags(final Activity activity) {
+    public static void setSoftInputModeAdjustResize(final Activity activity) {
         // TODO: The flag is deprecated for API 30 and WindowInset API should be used
         // https://developer.android.com/reference/android/view/WindowManager.LayoutParams#SOFT_INPUT_ADJUST_RESIZE
         // https://medium.com/androiddevelopers/animating-your-keyboard-fb776a8fb66d

termux-shared/src/main/java/com/termux/shared/view/ViewUtils.java

@@ -0,0 +1,98 @@
+package com.termux.shared.view;
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.ContextWrapper;
+import android.graphics.Rect;
+import android.util.TypedValue;
+import android.view.View;
+
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatActivity;
+
+public class ViewUtils {
+
+    /**
+     * Check if a {@link View} is fully visible and not hidden or partially covered by another view.
+     *
+     * https://stackoverflow.com/a/51078418/14686958
+     *
+     * @param view The {@link View} to check.
+     * @return Returns {@code true} if view is fully visible.
+     */
+    public static boolean isViewFullyVisible(View view) {
+        Rect[] windowAndViewRects = getWindowAndViewRects(view);
+        if (windowAndViewRects == null)
+            return false;
+        return windowAndViewRects[0].contains(windowAndViewRects[1]);
+    }
+
+    /**
+     * Get the {@link Rect} of a {@link View} and the  {@link Rect} of the window inside which it
+     * exists.
+     *
+     * https://stackoverflow.com/a/51078418/14686958
+     *
+     * @param view The {@link View} inside the window whose {@link Rect} to get.
+     * @return Returns {@link Rect[]} if view is visible where Rect[0] will contain window
+     * {@link Rect} and Rect[1] will contain view {@link Rect}. This will be {@code null}
+     * if view is not visible.
+     */
+    @Nullable
+    public static Rect[] getWindowAndViewRects(View view) {
+        if (view == null || !view.isShown())
+            return null;
+
+        // windowRect - will hold available area where content remain visible to users
+        // Takes into account screen decorations (e.g. statusbar)
+        Rect windowRect = new Rect();
+        view.getWindowVisibleDisplayFrame(windowRect);
+
+        // If there is actionbar, get his height
+        int actionBarHeight = 0;
+        Context context = view.getContext();
+        if (context instanceof AppCompatActivity) {
+            androidx.appcompat.app.ActionBar actionBar = ((AppCompatActivity) context).getSupportActionBar();
+            if (actionBar != null) actionBarHeight = actionBar.getHeight();
+        } else if (context instanceof Activity) {
+            android.app.ActionBar actionBar = ((Activity) context).getActionBar();
+            if (actionBar != null) actionBarHeight = actionBar.getHeight();
+        }
+
+        // windowAvailableRect - takes into account actionbar and statusbar height
+        Rect windowAvailableRect;
+        windowAvailableRect = new Rect(windowRect.left, windowRect.top + actionBarHeight, windowRect.right, windowRect.bottom);
+
+        // viewRect - holds position of the view in window
+        // (methods as getGlobalVisibleRect, getHitRect, getDrawingRect can return different result,
+        // when partialy visible)
+        Rect viewRect;
+        final int[] viewsLocationInWindow = new int[2];
+        view.getLocationInWindow(viewsLocationInWindow);
+        int viewLeft = viewsLocationInWindow[0];
+        int viewTop = viewsLocationInWindow[1];
+        int viewRight = viewLeft + view.getWidth();
+        int viewBottom = viewTop + view.getHeight();
+        viewRect = new Rect(viewLeft, viewTop, viewRight, viewBottom);
+
+        return new Rect[]{windowAvailableRect, viewRect};
+    }
+
+    /** Get the {@link Activity} associated with the {@link Context} if available. */
+    @Nullable
+    public static Activity getActivity(Context context) {
+        while (context instanceof ContextWrapper) {
+            if (context instanceof Activity) {
+                return (Activity)context;
+            }
+            context = ((ContextWrapper)context).getBaseContext();
+        }
+        return null;
+    }
+
+    /** Convert value in device independent pixels (dp) to pixels (px) units. */
+    public static int dpToPx(Context context, int dp) {
+        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, context.getResources().getDisplayMetrics());
+    }
+
+}