Improve input method compatibility and add enable/disable input composing property.

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

@@ -2,20 +2,16 @@
 
 import android.annotation.SuppressLint;
 import android.app.AlertDialog;
-import android.content.ClipData;
-import android.content.ClipboardManager;
 import android.content.Context;
 import android.media.AudioManager;
 import android.os.Environment;
-import android.text.TextUtils;
 import android.view.Gravity;
 import android.view.InputDevice;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
 import android.view.View;
 import android.widget.EditText;
 import android.widget.ListView;
-import android.widget.Toast;
 
 import com.termux.R;
 import com.termux.app.TermuxActivity;
@@ -216,6 +212,11 @@ public boolean shouldEnforceCharBasedInput() {
         return mActivity.getProperties().isEnforcingCharBasedInput();
     }
 
+    @Override
+    public boolean isInputComposingDisabled() {
+        return mActivity.getProperties().isInputComposingDisabled();
+    }
+
     @Override
     public boolean shouldUseCtrlSpaceWorkaround() {
         return mActivity.getProperties().isUsingCtrlSpaceWorkaround();

terminal-view/src/main/java/com/termux/view/ChangeWatcher.java

@@ -0,0 +1,71 @@
+package com.termux.view;
+
+import android.content.Context;
+import android.text.Editable;
+import android.text.Selection;
+import android.text.SpanWatcher;
+import android.text.Spannable;
+import android.text.TextWatcher;
+import android.view.inputmethod.InputMethodManager;
+
+import com.termux.view.inputmethod.TerminalInputConnection;
+
+class ChangeWatcher implements TextWatcher, SpanWatcher {
+    final TerminalView mTerminalView;
+
+    ChangeWatcher(TerminalView terminalView) {
+        this.mTerminalView = terminalView;
+    }
+
+    private void sendUpdateSelection() {
+        final InputMethodManager imm = (InputMethodManager) mTerminalView.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
+        final Editable text = mTerminalView.getImeBuffer();
+        if (imm != null && text != null) {
+            final int selectionStart = Selection.getSelectionStart(text);
+            final int selectionEnd = Selection.getSelectionEnd(text);
+
+            final int candStart = TerminalInputConnection.getComposingSpanStart(text);
+            final int candEnd = TerminalInputConnection.getComposingSpanEnd(text);
+            imm.updateSelection(mTerminalView, selectionStart, selectionEnd, candStart, candEnd);
+        }
+    }
+
+
+    private void spanChange(Object what) {
+        if (what == Selection.SELECTION_START || what == Selection.SELECTION_END) {
+            sendUpdateSelection();
+        }
+    }
+
+    @Override
+    public void onSpanAdded(Spannable text, Object what, int start, int end) {
+
+        spanChange(what);
+    }
+
+
+    @Override
+    public void onSpanRemoved(Spannable text, Object what, int start, int end) {
+        spanChange(what);
+
+    }
+
+    @Override
+    public void onSpanChanged(Spannable text, Object what, int ostart, int oend, int nstart, int nend) {
+        spanChange(what);
+    }
+
+    @Override
+    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+
+    }
+
+    @Override
+    public void onTextChanged(CharSequence s, int start, int before, int count) {
+    }
+
+    @Override
+    public void afterTextChanged(Editable s) {
+        mTerminalView.invalidate();
+    }
+}

terminal-view/src/main/java/com/termux/view/TerminalRenderer.java

@@ -1,6 +1,7 @@
 package com.termux.view;
 
 import android.graphics.Canvas;
+import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.Typeface;
@@ -55,7 +56,8 @@ public TerminalRenderer(int textSize, Typeface typeface) {
 
     /** Render the terminal to a canvas with at a specified row scroll, and an optional rectangular selection. */
     public final void render(TerminalEmulator mEmulator, Canvas canvas, int topRow,
-                             int selectionY1, int selectionY2, int selectionX1, int selectionX2) {
+                             int selectionY1, int selectionY2, int selectionX1, int selectionX2,
+                             CharSequence imeBuffer) {
         final boolean reverseVideo = mEmulator.isReverseVideo();
         final int endRow = topRow + mEmulator.mRows;
         final int columns = mEmulator.mColumns;
@@ -153,6 +155,12 @@ public final void render(TerminalEmulator mEmulator, Canvas canvas, int topRow,
             }
             drawTextRun(canvas, line, palette, heightOffset, lastRunStartColumn, columnWidthSinceLastRun, lastRunStartIndex, charsSinceLastRun,
                 measuredWidthForRun, cursorColor, cursorShape, lastRunStyle, reverseVideo || invertCursorTextColor || lastRunInsideSelection);
+
+            if (row == cursorRow) {
+                //ime fore color
+                int imeFore = Color.DKGRAY;
+                drawImeBuffer(canvas, heightOffset, cursorCol, mEmulator.mColors.mCurrentColors[TextStyle.COLOR_INDEX_CURSOR], imeFore, imeBuffer, columns);
+            }
         }
     }
 
@@ -239,6 +247,35 @@ private void drawTextRun(Canvas canvas, char[] text, int[] palette, float y, int
         if (savedMatrix) canvas.restore();
     }
 
+    private void drawImeBuffer(Canvas canvas, float y, int cursorX, int cursorColor, int imeFore, CharSequence imeBuffer, int columns) {
+        // draw ime buffer
+        final int bufLen = imeBuffer.length();
+        if (bufLen > 0) {
+            float cursorHeight = mFontLineSpacingAndAscent - mFontAscent;
+
+            final float left = cursorX * mFontWidth;
+            final int maxWidth = (int) (columns * mFontWidth - left);
+            if (maxWidth > 0) {
+                final float[] widths = bufLen > asciiMeasures.length ? new float[bufLen] : asciiMeasures;
+
+                final int count = mTextPaint.getTextWidths(imeBuffer, 0, bufLen, widths);
+                int offset = count - 1;
+                int width = 0;
+                for (; offset >= 0 && width < maxWidth; offset--) {
+                    width += widths[offset];
+                }
+                offset++;
+
+                mTextPaint.setColor(cursorColor);
+                canvas.drawRect(left, y - cursorHeight, left + width,
+                    y, mTextPaint);
+
+                mTextPaint.setColor(imeFore);
+                canvas.drawText(imeBuffer, offset, bufLen, left, y - mFontLineSpacingAndAscent, mTextPaint);
+            }
+        }
+    }
+
     public float getFontWidth() {
         return mFontWidth;
     }

terminal-view/src/main/java/com/termux/view/TerminalView.java

@@ -14,6 +14,8 @@
 import android.os.SystemClock;
 import android.text.Editable;
 import android.text.InputType;
+import android.text.SpannableStringBuilder;
+import android.text.Spanned;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.view.ActionMode;
@@ -39,6 +41,7 @@
 import com.termux.terminal.KeyHandler;
 import com.termux.terminal.TerminalEmulator;
 import com.termux.terminal.TerminalSession;
+import com.termux.view.inputmethod.TerminalInputConnection;
 import com.termux.view.textselection.TextSelectionCursorController;
 
 /** View displaying and interacting with a {@link TerminalSession}. */
@@ -95,6 +98,7 @@ public final class TerminalView extends View {
 
     private static final String LOG_TAG = "TerminalView";
 
+    private final SpannableStringBuilder imeBuffer = new SpannableStringBuilder("");
     public TerminalView(Context context, AttributeSet attributes) { // NO_UCD (unused code)
         super(context, attributes);
         mGestureRecognizer = new GestureAndScaleRecognizer(context, new GestureAndScaleRecognizer.Listener() {
@@ -221,6 +225,11 @@ public void onLongPress(MotionEvent event) {
         mScroller = new Scroller(context);
         AccessibilityManager am = (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
         mAccessibilityEnabled = am.isEnabled();
+
+
+        imeBuffer.setSpan(new ChangeWatcher(this),
+            0, imeBuffer.length(),
+            Spanned.SPAN_INCLUSIVE_INCLUSIVE | (100 << Spanned.SPAN_PRIORITY_SHIFT));
     }
 
 
@@ -265,8 +274,25 @@ public boolean attachSession(TerminalSession session) {
         return true;
     }
 
+
+    public Editable getImeBuffer() {
+        return imeBuffer;
+    }
+
     @Override
     public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
+        if(!mClient.isInputComposingDisabled()){
+            outAttrs.imeOptions =
+                EditorInfo.IME_FLAG_NO_EXTRACT_UI |
+                    EditorInfo.IME_FLAG_NO_FULLSCREEN |
+                    EditorInfo.IME_FLAG_NO_ENTER_ACTION;
+            outAttrs.inputType = InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
+            outAttrs.hintText = "";
+            outAttrs.initialSelStart = -1;
+            outAttrs.initialSelEnd = -1;
+            outAttrs.initialCapsMode = 0;
+            return new TerminalInputConnection(this);
+        }
         // Ensure that inputType is only set if TerminalView is selected view with the keyboard and
         // an alternate view is not selected, like an EditText. This is necessary if an activity is
         // initially started with the alternate view or if activity is returned to from another app
@@ -975,7 +1001,7 @@ protected void onDraw(Canvas canvas) {
                 mTextSelectionCursorController.getSelectors(sel);
             }
 
-            mRenderer.render(mEmulator, canvas, mTopRow, sel[0], sel[1], sel[2], sel[3]);
+            mRenderer.render(mEmulator, canvas, mTopRow, sel[0], sel[1], sel[2], sel[3], imeBuffer);
 
             // render the text selection handles
             renderTextSelection();

terminal-view/src/main/java/com/termux/view/TerminalViewClient.java

@@ -36,7 +36,7 @@ public interface TerminalViewClient {
 
     boolean isTerminalViewSelected();
 
-
+    boolean isInputComposingDisabled();
 
     void copyModeChanged(boolean copyMode);